Reducing molecular weight of polysaccharides by electron beam treatment

FIELD: chemistry.

SUBSTANCE: method for depolymerisation of polysaccharides of galactomannan, as well as xanthan, type, preferably galactomannans, to specified molecular weight by high-energy electron beam treatment. Preferential galactomannans for the said type of treatment are guar gum, guar endosperm and hydroxypropylguar. According to preferential version of the method, guar gum is depolymerised, preferably, to molecular weight of ca. 100000 daltons to ca. 200000 daltons.

EFFECT: depolymerised guar has lower polydispersity and can be used for oil well fracturing in order to gain in oil yield.

16 cl, 15 tbl, 6 dwg

 

Cross-reference to related applications the invention

Claims of this application have the advantage over the prior patent application US No. 60/391,320, registered on 25 June 2002, according to §119 of title 35 of the code of laws of the US.

The technical field to which the invention relates.

Objects of the present invention is a method of irradiation of polysaccharide polymers, in particular, galactomannans, such as guar gum, xanthan gum and xanthan gum, a high-energy electron beams to depolymerization of these polymers, as well as obtained according to the method of the polymers.

Background of invention

Polysaccharides, in particular, galactomannans, such as guar, hydroxypropanoyl, xanthan gum and xanthan gum, have many uses. Guar in the form of a resin mainly used in food and personal care products to impart density. Resin on its strength as a thickener exceeds the starch in five to eight times. Guar gum is also used as an excipient in the fracturing of oil production.

Guar gum is a natural adhesive that is present in the seeds of leguminous plant Cyamopsis tetragonolobus. The seeds consist of a pair of viscous nelomky endospermic departments, hereafter called the endosperm g the Ara. The endosperm of guar contains guar gum, but it is too viscous and it is extremely difficult to grind into powder with the aim of separating the resin. After processing of natural guar gum obtained as a yellow powder, and it has a molecular mass of between approximately 2000000 Dalton and 5000000 Dalton.

In some applications the guar resin, such as food production and compositions for personal care, the gap layers in oil wells and oil production, for best results it is preferable to use a material with a relatively low molecular weight. For example, when using the guar resin as an auxiliary substances in fracturing in oil wells is preferable that the resin had a molecular weight of between 100000 daltons and 250,000 daltons, since the resin with such lower molecular weight better achieved high ability to spread in the cracks, and the low degree of formation damage affects the operations of the industry. In addition, given that used in oil guar gum modified with additives, forming cross-links between the polymer chains, as will be discussed below, depolimerizovannogo guar must be able to cross-stitching.

Guar gum is more low molecular mass obtained by depolymerization of natural resins. One of the used current method of depolymerization of guar is the handling of hydrogen peroxide. However, depolymerization by treatment with hydrogen peroxide has the disadvantage that it is difficult to control from the point of view of obtaining the guar resin with a pre-defined range of molecular masses. More specifically, treatment with hydrogen peroxide in the General case leads to depolimerizovannogo garolim resin with a polydispersity in the range from 3 to 5, which seems too high value. (Polydispersity is defined as the mass-average molecular mass of the processed guar referred to srednetsenovoj molecular mass.) Depolimerizovannogo guar gum used in the extraction of oil from wells, must have a value of polydispersity not higher than approximately 3.0V. This method of depolymerization also leads to the formation of the guar resin agglomerates with hydrogen peroxide, which reduces the purity depolimerizovannogo Guara.

The US patent No. 5,273,767 relates to a method of obtaining modified quickly hydratious xanthan gum and/or guar resin and sterilization of food products containing xanthan gum and/or guar gum, by irradiation. The irradiation can be carried out using high-energy electron beam at the level of between about 0.1 and 4.5 mrad).

The US patent No. 6,383,344 B1 discloses a method of reducing the molecular weight polysaccharide polymers, in particular, tiomocheva acid and carboxymethylcellulose, through irradiation of polymers. Specific types of irradiation disclosed in the patent, are gamma rays and microwaves. The preferred type of irradiation disclosed in the patent, is gamma radiation. However, the use of gamma radiation requires careful safety precautions, because gamma radiation generated by the radioactive source, highly toxic.

In the article, King and others, entitled "the Influence of gamma radiation on guar gum, resin carob (tragacanth gum and gum karaya". Food Hydrocolloids, .VI, No. 6, str-569, 1993, reported the results of processing of galactomannans, such as guar gum, low doses of gamma radiation. It is reported that the products obtained have a low viscosity. The article indicates that the viscosity of the guar solutions of resins and resin carob decreases with increasing dose of gamma radiation under the condition of irradiation in the form of a dry powder.

Published patent GB No. 1,255,723 refers to the depolymerization simple water-soluble cellulose ether irradiation of high-energy electron beams. The process involves the irradiation of a layer free of the current particle is vodorastvorimogo simple cellulose ether, moreover, the layer has a uniform thickness selected so that she was within 10% of the penetration depth of the beam. Simple cellulose ether is substituted polysaccharide, but not galactomannans. In the patent is not disclosed to the depolymerization of the polymers, leading to the formation of products having a predefined range of molecular masses or the value of polydispersity, less than, approximately, 3,0.

According to US patent No. 5,916,929 irradiation of polymeric materials leads to two types are essentially different products. Some high molecular weight polymers, such as polyethylene and its copolymers, polybutadiene, polyvinyl chloride, natural rubber, polyamides, polycarbonate and polyesters, enter into the processes of binding molecules are cross-linked. Cross-linking increases the molecular weight of the polymer and increases its melt viscosity, as is shown by measuring the rate of flow of the melt, i.e. the numerical value of the rate of flow of the melt decreases. The second type polymers, such as polypropylene, grades and fluorocarbon polymers including polytetrafluoroethylene by irradiation with high-energy ionizing radiation is exposed, as is known, the polymer degradation. This cutting of the polymer chain which tends to reduce the molecular weight of the polymer, that is reflected by reducing the viscous properties of the melt, as shown by the measured increase in the rate of melt flow (MFR).

Summary of the invention

The aim of the present invention is the depolymerization of polysaccharides, in particular, galactomannans, such as guar gum and xanthan gum, in order to obtain a product having a given lower molecular weight falling within a very narrow mass range.

Another objective of the present invention is the depolymerization of the endosperm of guar to a given molecular weight to facilitate work with the endosperm of guar and retrieve the guar resin from the endosperm of guar.

Another purpose of this invention is the provision of a method for the depolymerization of polysaccharides and, in particular, the guar resin, providing a low level of impurities in the final product.

Another purpose of this invention is the provision of a method for the depolymerization of polysaccharides, which can be carried out at approximately room temperature and without the use of radioactive materials as a source depolymerizes radiation.

Another objective of the present invention to provide a depolimerizovannogo of galactomannan and xanthan resin, which have a defined molecular weight and polides rnost less than about 3.0, and which are easily subjected to hydration.

These and other objectives can be achieved through used in the present invention methods, according to which the polysaccharide polymers, in particular xanthan gum and galactomannans, such as guar gum, xanthan gum, endosperm guar swollen in water endosperm of guar and powder hydroxypropylamino will depolymerized by irradiation of high-energy electron beam. According to the present invention guar gum having a molecular weight of not less than 2000000 Dalton, depolymerized to the desired lower molecular weight. These depolimerizovannogo products have application in the food industry, the production of cosmetics and pharmaceuticals and other industrial sectors, such as the production of flowable pesticides, liquid nutritional supplements, cleaning products, ceramics and coatings. In a preferred embodiment of the present invention, the depolymerization carried out so that the resulting guar resin had a molecular weight below about the 700,000 daltons. In a more preferred embodiment of the present invention depolymerization carried out so that the resulting galactomannan had a molecular weight below approximately 500000 daltons. In persons who NGOs preferred embodiment of the present invention depolymerization carried out so in order to produce galactomannan had a molecular weight below approximately 300000 daltons. In the most preferred embodiment of the present invention depolymerization carried out so that the resulting galactomannan had a molecular weight of between approximately 100000 daltons and approximately 250000 daltons and a polydispersity less, approximately 3.0, and that not less than 90% received galactomannan passed in gidratirovannuyu form within three (3) minutes. The method according to the present invention is also suitable for depolymerization other galactomannans. The object of the present invention is also depolimerizovannogo product, in particular, guar gum and substituted guar gum, obtained by method described here, and, most preferably, the product having a specified molecular weight and lying within the ranges shown above masses, having a polydispersity of less than about 3.0 and hydratherapy at least 90% within three (3) minutes. These depolimerizovannogo products are particularly useful as auxiliary substances for fracturing in oil production.

The type and dose of high-energy electron beams used in the implementation of the present invention will vary depending on the type of polysaccharide on the of iMER, the desired degree of reduction of the molecular weight and the desired speed of depolymerization. When depolymerization of the guar resin, the irradiation dose of the electron beam, which is irradiated guar gum, will preferably range from about 1 Mrad to about 15 Mrad, but higher or lower doses of radiation of the electron beam than lying in this preferred range may also be used.

Brief description of drawings

Figure 1 represents a graph showing the decrease in molecular weight of the guar resin obtained from the endosperm of guar, guarav Jaguar 6003VT and Jaguar 8000, depending on exposure to increasing doses of radiation from high-energy electron beam.

Figure 2 represents a graph showing the molecular weight of the guar resin obtained from guar powder, the endosperm of guar and hydroxypropylamino when exposed to high energy electron beams.

Figure 3 represents a graph showing the growth in the relative water solubility of the materials obtained from guar powder or hydroxypropylamino depending on exposure to increasing doses of radiation.

Figure 4 is a graph showing the reduction of the mass-average molecular weight and srednetsenovoj molecular weight of the guar see the crystals, derived from guar Agent AT-2001, including hydroxypropanoic and a small amount of sodium hydroxide.

Figure 5 represents a graph showing the effect of sample thickness on srednecenovogo molecular mass and mass-average molecular weight depolimerizovannogo Guara.

Figure 6 represents a graph showing the effect of sample thickness on the polydispersity of irradiated guar.

Detailed description of the invention

A. Polysaccharides

The term "polysaccharide"as used in context, refers to a polymer containing a repeating sacharine fragments, including starch, Polydextrose, lignocellulose, cellulose and their derivatives (e.g. methylcellulose, ethylcellulose, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose acetate, butyrate cellulose acetate, propionate, cellulose acetate, derivatives of starch and amylase, amylopectin and its derivatives, as well as other chemically and physically modified starches and the like.

B. Galactomannan

The galactomannans are polysaccharides consisting mainly of monosaccharides mannose and galactose. Mannose links form a chain consisting of many hundreds (1→4)-β-D-mannopyranosyl residues with 1→6-related α-D-galactopyranosyl residues located at different distances in dependent on the STI from the original plants. The galactomannans of the present invention can be obtained from many sources. Such sources include guar gum, the endosperm of guar, cationic and nonionic guar, resin carob and the resin of cesalpinia prickly, as will be further described below. In addition, the galactomannan can be also obtained using classical synthetic methods, or by chemical modification of natural galactomannans.

1. Guar gum

Guar gum, which after grinding to a powder, often referred to as "the guar flour"is a natural adhesive that is present in the seeds of leguminous plant Cyamopsis tetragonolobus. Water-soluble fraction (85%), referred to as "guaran", consists of linear chains of (1→4)-β-D-mannopyranosyl links with attached 1→6-links α-D-galactopyranosyl links. The ratio of D-galactose to D-mannose in guarana is approximately 1:2. Guar gum may take the form of a whitish powder that is dispersible in hot or cold water. Guar gum can be purchased, for example, from Rhodia, Inc. (Cranbury, New Jersey), Hercules, Inc. (Wilmington, delawar) and TIC Gum, Inc. (Belcamp, Maryland).

2. The endosperm of guar

The seeds of the guar consist of a pair of viscous nelomky endospermic departments, hereinafter referred to as "the endosperm of guar", between whom concluded brittle embryo. After peeling the seeds split, germ (43-47% of the seed) are removed during sorting, and grind the endosperm. Located in the endosperm resin contained in small cells with water-insoluble wall. In these cells the resin slowly dispersed in water and, consequently, it is desirable to ensure the destruction of the walls of the cells, as well as obtaining particles of small size.

Reportedly, the endosperm contains about 78-82% of the polysaccharide of galactomannan and small amounts of protein substances, inorganic salts, water-insoluble resin and cell membranes, as well as residual amounts of the seed coat and embryo. They are extremely viscous and difficult to grinding.

3. Resin carob

Resin carob or resin carob (Ceratonia green) is purified endosperm of the seeds of the carob tree, ceratonia siliqua. The ratio of galactose and mannose for this type of resin is about 1:4. Growing carob for a long time and is widely known in the industry resin. This type of resin is available commercially and can be purchased from TIC Gum, Inc. (Belcamp, Maryland), and Rhodia, Inc. (Cranbury, New Jersey).

4. Resin of cesalpinia prickly

The resin of cesalpinia prickly obtained from the purified resin seeds cesalpinia prickly. The ratio of Gal which of ctazy and mannose is about 1:3. In the US there is no commercial production of tar cesalpinia prickly, but the resin can be obtained from various sources outside the US.

C. Modified galactomannan

Other interest galactomannans are modified galactomannan, including carboxymethylate, carboxyphenoxypropane, cationic hydroxypropanoic, hydroxyalkyl, including hydroxyether, hydroxypropanoyl, hydroxybutyric and higher hydroxyalkanoate, carboxylique, including carboxymethylate, carboxypropanoyl, carboxybutyl and higher carboxylique, gidroksietilirovanny, hydroxypropylamino and karboksimetilirovaniya derivatives guarana, gidroksietilirovanny and karboksimetilirovaniya derivatives carabina (resin carob), hydroxypropylamino and karboksimetilirovaniya derivative resin Cassia Tora and modified galactomannan or galactomannans resin. Preferred modified galactomannan is hydroxypropanoic with a low degree of substitution, for example, below 0.6.

, Xanthan gum

Interest xanthane are xanthan gum and gel. Xanthan gum is a polysaccharide resin produced Xathomonas campestris. Xanthan gum contains as main hexonic jingle is in D-glucose, D-mannose and D-glucuronic acid, and also contains pyruvic acid and is partially acetylated.

According to the present invention the polysaccharide polymers, in particular, galactomannan, such as solid guar gum, and xanthan gum,such as xanthan gum, are irradiated by high-energy electron beams. Irradiation leads to depolymerization of the polymer to a controlled molecular weight. The dose and the duration of the exposure depends on the specific subject material processing. The type and dose of the applied radiation may vary depending on the specific polymer of objects to be processed according to the present invention. The method according to the present invention is applicable to a wide range of polysaccharides, but in particular it is applicable to galactomannans and modified galactomannans. This method is especially useful when the depolymerization of guar resin or its derivatives, such as hydroxypropanoic in the form of a powder or endosperm.

The polymer treated according to the present invention, is in the solid phase before and during treatment. The term "solid phase" includes powders, granules, flakes, particles, and other similar forms. Irradiation is exposed directly to the polymer in the solid phase, preferably as progress poly the EPA in trays on a continuous conveyor production line. According to the present invention is designed to depolymerization of solid polymer is placed in a tray with such a layer thickness that provides penetration through the solid material of high-energy electron beams. The polydispersity can be controlled by selecting the thickness of the material. The polydispersity is reduced if all the material is penetrated by the electron beam. In order to get a good amount of polydispersity for depolimerizovannogo product layer depolymerizing solid material should have a sufficiently uniform thickness. For security reasons, dedicated to the processing of the polymer can be coated transparent for radiation of a thin plastic film. The tray is placed on the conveyor inside the camera exposure. The polymer is irradiated with high energy electron beams specified dose of radiation, depending on the degree of depolymerization of the polymer, which should be obtained. In the technological processes associated with the irradiation dose is defined as the amount of energy absorbed by the target material. The dose units are either gray or megarad. One kilogray equal to 1000 joules per kilogram. One megarad equal to 1000000 erg per gram. Accordingly, 1 megarad equal to 10 kilogram. The preferred dose is between, is roughly, 1 and approximately 15 megarad or from about 10 to about 150 kilogray (GSR) and can be obtained using a 4.5 MeV generator operating at a current of 15 milliamps. Such a generator can be purchased from E-Beam Services, Inc. from Plainview, new York.

The dose of radiation is the amount of time that is required to ensure that the dose required for the depolymerization of the polymer to a predetermined molecular weight. This power is directly related to how much time is required to achieve the specified dose and, consequently, to the amount of time during which the polymer is irradiated with ionizing radiation. Beams of high power quickly generate radiation dose. As indicated in table 1, even the electron beam of lower power (1 kW) ensure a given dose of irradiation target 40 times faster than gamma irradiation of equivalent power. The use of high-energy electron beams allows to achieve much higher performance when receiving depolimerizovannogo the guar resin.

Table 1

Comparison of radiation doses for technology of gamma irradiation and electron beam technology
gamma irradiationthe exposed is the electron beam
The target dose20 kGy20 kGy
Dose (depending on technology)10 kGy/h400 kGy/h
The time required to achieve the specified dose2 h (120 min)of 0.05 hours (3 minutes)

Irradiation of the polymer by high-energy electron beams is preferably carried out at room temperature, but it can also be carried out at higher and lower temperatures.

Preferred high-voltage electron beam generator, providing a dose of 1-10 MeV, as the generated beams penetrate deeper into the material, thereby making it possible to irradiate thicker layers of material. Can be used and energy above 10 MeV, but this is not preferred, because it can cause radioactive heavy elements. High-voltage electron beam generator can be purchased from Electron Solutions Inc. and Science Research Laboratory, Somerville, Massachusetts, Ion Beam Applications, Louvan-La-Neuve, Belgium, and The Titan Corporation, San Diego, California.

Low-voltage electron beam generator (150 Kev - 1 MeV) is also preferred. The material is irradiated in the form of a layer by passing through the generator; the exposure can be optionally carried out after mechanical grinding mA is eriala to powder. Such a generator is usually cheaper and does not require concrete screen. Low-voltage electron beam generator can be purchased from Energy Sciences, Inc., Wilmington, Massachusetts (model EZCure), Radiation Dynamics Inc., Edgewood, new York (model Easy E-beam) and Electron Solutions Inc., Somerville, Massachusetts (model EB-APR). Traditionally this equipment is used mainly for heat treatment of surfaces by radiation.

As mentioned above, the degree of depolymerization is influenced by the molecular weight of the original polymer, subjected to processing, and the target molecular weight depolimerizovannogo product. Guar gum has a molecular mass of more than 2000000 daltons, typically between 2000000 Dalton and 5000000 daltons. In a preferred embodiment of the present invention, the polymer will depolymerized to molecular weight below about the 700,000 daltons, more preferably up to molecular weight below approximately 500000 daltons, even more preferably up to molecular weight below approximately 300000 daltons, most preferably up to molecular weight lying between approximately 100000 daltons and 250,000 daltons. As a result of application of the present invention, galactomannan polymers can be depolymerizer to products with a lower molecular weight than the above, and the most is her preferred lying between approximately 100000 daltons and approximately 250000 Dalton.

As discussed in more detail below, depolimerizovannogo galactomannan become hydrated state for more than 90% within three (3) minutes.

As stated above, depolimerizovannogo the guar used to facilitate oil production. The performance of oil and gas wells can be increased by breaking and opening the oil and gas formations using hydraulic pressure. In this process, known as hydraulic fracturing, used solution hydroxypropranolol resin and similar gelling agents. When this process has a high viscosity fluid for fracturing containing proppants, such as sand, is pumped under high pressure into oil or gas formation and, thus, leads to fractures in the reservoir. Proppants holds the cracks open when removing the hydraulic pressure. As a result, increases the rate of production of oil and gas.

The galactomannans, such as guar or hydroxypropanoic add in the fluid for fracturing to increase its viscosity and ability to transfer proppant. In addition, in the case of the guar resin and endosperm of guar, chiroxiphia and similar viscosity and the ability to transfer proppant can grow even stronger in the use of additives for cross stitching. Some well-known additives for cross-linkage include borates, as described in US patent No. 3,974,077, and titanate or zirconate ORGANOMETALLIC agents for cross-linkage, as described in US patents No. 4,657,080 and 4,686,052, respectively. It was, however, found that the fluid for fracturing with excessive viscosity can fill cracks and, consequently, reduce the rate of production of oil or gas. The decrease in viscosity of the fluid for fracturing by replacing the original the guar resin depolimerizovannogo the guar resin obtained according to the present invention, would ease this problem.

As mentioned above, depolimerizovannogo xanthan gum galactomannan and xanthan resin used in the food industry, the production of cosmetics and pharmaceuticals and other industrial sectors, such as the production of flowable pesticides, liquid nutritional supplements, cleaning products, ceramics and coatings. More specifically, depolimerizovannogo guar could be used in the manufacture of various food products, including confectionery, processed fruits and vegetables, beverages, sauces and dressings, to give them the proper consistency. Depolimerizovannogo galactomannan could also be used to give a proper consistence dairy products there, cheese, soups and feed for domestic animals, as well as to give the proper consistency and prelink water in meat products.

The following examples of the invention are given for illustrative purposes only. They in no way be considered as limiting the present invention.

Example 1

The following is an example of depolymerization of the guar resin, the endosperm of guar and derivatives of guar by irradiation of high-energy electron beams.

The endosperm of guar, guar gum in the form of powder or hydroxypropranolol resin in powder form was placed in a container and covered with very thin plastic film. The samples were irradiated by electron beam, obtained with the help of 4.5 MeV generator operating at a beam current of 15 milliamps, and aimed at the upper surface of the tray. Were involved irradiation dose of 1 Mrad 3 mrad 5 Mrad 10 Mrad and 15 Mrad.

After irradiation, the molecular weight of the treated sample was analyzed using gel permeation chromatography (column: Supelco Progel-TSK G3000PWXLand G6000PWXLseries-connected; mobile phase: 55 mM Na2SO4, of 0.02% NaN3; volumetric flow rate: 0.6 ml/min; detector: detector refractive index of a Waters 410; injected volume: 200 Ál; temperature: 40°). The samples were dissolved in vignau phase before reaching the mass fraction of a substance in a solution of 0.025%. A calibration curve was built using stachyose and two samples of the guar resin with a molecular mass 667, 58000 and 2000000 daltons. The results obtained are presented in table 2.

The decrease in molecular weight with increasing dose clearly shown by the example of three different types of samples (figure 1). The degree of depolymerization increased with increasing irradiation doses. The degree of depolymerization was similar for all materials, and any significant changes to the guar powder resin, the endosperm of guar or powder hydroxypropranolol resin was not observed. You can find a correlation between the degree of depolymerization or molecular mass with dose (figure 1) and, thus, it is possible to easily predict the decrease of molecular weight for a given dose on the condition that famous original molecular weight before irradiation.

Table 2

Molecular mass distribution of irradiated guar
SampleThe molecular weight at the maximum of the distribution (Mρ)The mass-average molecular mass (Mw)Brednikova molecular mass (Mn)The polydispersity (Mw/Mn)
powder Hydra is xiropigado, 1 Mrad4170005130001490003,44
powder hydroxypropylamino, 3 Mrad173000227000670003,35
powder hydroxypropylamino, 5 Mrad117000is 141,000430003,28
powder hydroxypropylamino, 10 Mrad647007750025200of 3.07
hydroxypropanoic, 15 Mrad435005380017400is 3.08
powder guar 0 rad2960000286000012000002,37
powder guar 1 Mrad4740005710001610003,54
powder guar 3 Mrad196000249000789003,16
powder guar 5 Mrad110000 132000418003,16
powder guar 10 Mrad5990068100217003,13
powder guar 15 Mrad3990046400149003,11
the endosperm of guar, 1 Mrad5880007060002240003,16
the endosperm of guar, 3 Mrad241000314000of 118,0002,66
the endosperm of guar, 5 Mrad120000140000494002,83
the endosperm of guar, 10 Mrad8490094200350002,69
the endosperm of guar, 15 Mrad4720058000194002,99

Example 2

The following is an example of depolymerization of different types of guar with lower beam energy.

The endosperm of guar (DPS), the guar powder resin (Jaguar 6003VT) is hydroxypropranolol resin (HPG, Jaguar 8000) was irradiated with a dose of 10 Mrad using a 200 Kev beam Energy Science Incorporation. Molecular weight was measured by the same method which was described above. It is not surprising that the powder forms a Jaguar 6003VT and 8000 were subjected to depolymerization, whereas the effect of irradiation on the endosperm was very small (see table 3). Compared with high-energy electron beams absorbed dose was significantly reduced due to the limited penetrating power of the electron beam. Powdered samples Jaguar 6003VT and 8000 indeed received a certain dose and was subjected to depolymerization, because the powder was spread a very thin layer. However, it was noted the relatively high polydispersity (3-4) depolimerizovannogo product compared to the product obtained by irradiation beams at higher energies, the polydispersity which usually was 2-3. On the other hand, the penetration depth of the radiation in the endosperm was too small to cause any appreciable depolymerization of the latter. At least half of the energy was absorbed in plastic packaging, although the system was delivered to the surface dose of 10 Mrad. These results show that the depolymerization under the action of low-energy beams are possible with proper placement of the material on vergemoli action of the beam, with a suitable thickness/density.

Table 3

Depolymerization of guar under the action of an energy beam at a dose of 10 Mrad
GuarThe molecular weight at the maximum of the distribution (Mρ)The mass-average molecular mass (Mw)Brednikova molecular mass (Mn)The polydispersity (Mw/Mn)
the endosperm of guar160000013100003110004,20
Jaguar 6003 VT171000231000699003,31
Jaguar 800016600030100065200to 4.62

Example 3

In this example, the depolymerization of the guar resin and endosperm of the guar was carried out with the aim of obtaining fluid used for fracturing in oil wells.

Were selected and depolimerization several different types of guar and derivatives of guar, namely the endosperm of the guar. Jaguar 8000 (HPG) and the basis of the agent AT-2001. (Base agent AT-2001 is taken to depolymerization guarderias product currently used in the oil industry, the generally accepted method of depolymerization which is what I handling hydrogen peroxide.) According to the specification (Material Safety Data Sheet), the basis of the agent AT-2001 contains more than 85% of 2-hydroxypropylamino the guar ether resin, less than 3% sodium hydroxide, and the remainder consists of water. These samples were Packed in plastic bags with smaller thickness than the effective thickness of the electron beam, and then irradiated at doses of 3.8 mrad using a 4.5 MeV generator triple electron beams. The molecular weight of the samples were analyzed within a few days after exposure. The results obtained are presented in table 4.

All samples of the endosperm of guar, Jaguar 8000 and the basics of the agent AT-2001 were successfully depolymerizer to the target mass range. Between the data for 4 parallel samples fundamentals agent AT-2001, as well as between the data for the two parallel samples of endosperm of guar have found no discrepancies. Was established excellent reproducibility of the results. Good value polydispersity (<3) were observed for all samples depolimerizovannogo of guar and its derivatives in comparison with currently used by guar, depolymerizes using hydrogen peroxide. Typical values of polydispersity observed at the present time for the chemical method, lie between 3 and 5. It should be noted that between the molecular masses of individual products were marked with a small R the differences, which can be easily eliminated by the selection of exposure. The reason for this is probably the difference in the composition of the endosperm of guar, Jaguar 8000 and the basics of the agent AT-2001.

Table 4

Reproducibility when depolymerization using electron beams
SampleThe molecular weight at the maximum of the distribution (Mρ)The mass-average molecular mass (Mw)Brednikova molecular mass (Mn)The polydispersity (Mw/Mn)
The basis of the agent AT-2001
#1of 118,000to 136,00052800to 2.57
#2116000133000546002,43
#3113000132000516002,56
#4114000130000527002,48
average11525013275052925of 2.51
standard deviation, % (n-1)1,91,92,32,7
Jaguar 8000 138000185000687002,69
the basis of the agent AT-2001 - swollen in water endosperm100000117000490002,39
the endosperm of guar #1185000238000945002,52
the endosperm of guar #2194000264000992002,66

Example 4

In this example, we studied the ability of foundations agent AT-2001 to cross-stitching.

Was determined viscosity individual solutions fundamentals agent AT-2001 and Jaguar 8000 in distilled water, and it was found that the values obtained lie in the expected based on the molecular masses of the samples, the range.

2.5% solution fundamentals agent AT-2001, the dose of 3.8 Mrad: viscosity of 14.5 CPS (at 511/s and a temperature of 75°F.

2.5% solution Jaguar 8000, dose of 3.8 Mrad: viscosity of 40 CPS (at 511/s and a temperature of 75°F.

The basis of the currently used agent AT-2001 is used in the oil industry in the cross-linked forms. It is important to ensure that the irradiated electron beam on the basis of the agent AT-2001 can also be cross-linked. This test will also help determine whether accompanied depolymerization upon irradiation of any significant changes to the functionality the selected groups. To clarify this solution fundamentals agent AT-2001 obtained by depolymerization fundamentals agent AT-2001 under irradiation, mixed with the initiator of cross stitching brown, as well as with sodium hydroxide to increase the pH. Within a few seconds the polymer solution turned into a gel. This test confirms that the irradiated electron beam on the basis of the agent AT-2001 capable of cross-linking under the influence of borax.

Examples 5-7

Examples 5-7 describe the depolymerization fundamentals agent AT-2001 in trial tests.

Control tests were conducted on the test device company Industrial Beam Applications (IBA), long island, new York. The samples were placed in plastic trays size 19×19×5 cm in the form of a thin layer and covered with a plastic cover. The depth of the material was determined on the basis of weight, density and area. The trays were irradiated on a movable stand. This varied surface dose, the energy of the electrons and the thickness of the samples. Also researched materials from other parties on the basis of the agent AT-2001.

For all treated materials show an increase in the intensity of staining with the increase of irradiation dose and at least close to one side of each tray was observed radiation shadow. After irradiation was observed more rapid hydration. The viscosity has reached more than 90% (maximum) in order for 3 minutes and was on a constant value for 10-15 minutes. According to this definition, 100% of the viscosity is defined as the full hydration. The viscosity of the irradiated materials was measured using the techniques described in the previous example. Viscosity measurements were used as an alternative to analyze the degree of depolymerization. Molecular weights were determined using gel permeation chromatography only for selected samples.

The degree of depolymerization of irradiated fundamentals agent AT-2001 was investigated by measuring the viscosity immediately after exposure (within two (2) hours and a few days later. Data were collected after full hydration of the polymer with water. It was shown that depolymerization continues after irradiation (see table 5). This is a General phenomenon during irradiation of solids, because the active particles are easily captured grating irradiated materials. These particles cause further reaction, which can last for seconds to days or even years, depending on the temperature of the solvent content of the material. Further investigation of this phenomenon in the framework of agent AT-2001 are described below.

Table 5

The decrease in viscosity with time after irradiation
Energy (MeV)1,21,21,21,21,21,2333
Dose (Mrad)3456786654
Thickness (cm)0,360,360,360,360,360,360,201,521,521,53
Viscosity105664626241826192333
Viscosity34283132121113142026
Viscosity35293232131114242126

Example 5 the effect of different irradiation doses on the depolymerization of the polymer.

Samples fundamentals agent AT-2001 were placed in trays with a layer thickness corresponding to the effective penetration depth for electrons specified energy. Produced different irradiation the dose at three energy levels: 1,2 MeV (with loss of energy to overcome the packing of 0.2 MeV), 1.5 and 3.0 MeV. At an energy of 1.2 MeV 90 g of the sample was distributed inside the tray (layer thickness of 3.6 mm for d=0.7), speed was irradiated with a dose of 1 Mrad to achieve different doses. At an energy of 1.5 MeV in each trial used a 160 g of the sample (6.4 mm for d=0.7)and the first samples were irradiated by a dose of 4 Mrad, and then the step was irradiated with doses of 1 Mrad to achieve doses of 5, 6 and 7 Mrad. At an energy of 3.0 MeV all irradiation was carried out in one stage. The viscosity was measured using viscometer Fann 35 production Baroid (Houston, Texas) at 300 rpm and 2.5% content of active material, while the estimated moisture content was ˜ 10% (see table 6). In order further testing the applicability tried to achieve a viscosity 23-28 CP.

Table 6

Depolymerization fundamentals agent AT-2001
Dose (Mrad)Viscosity (CP)
1,2 MeV/0,36 cm1.5 MeV/0,64 cm3.0 MeV/1,52 cm
13800--
296--
335--
4293626
5323421
6102714
71322-
811--

The results clearly indicate that the polymer was depolymerization. The viscosity decreases with increasing dose for all three energy levels of electrons. The molecular weight of selected samples, determined by gel permeation chromatography, is presented in table 7 and figure 4. A very good linear correlation is observed between the dose (D, Mrad) and as average mass (Mw)and srednetsenovoj (Mn) molecular mass:

Log(Mw)=5,6906-0,7881*log(D), correlation coefficient = -0,9979

Log(Mn)=5,2894-0,7176*log(D), correlation coefficient = -0,9987

The polydispersity for these samples ranged from 2.1 to 2.6 (see table 7), that was better than what was observed before. These desired values polydispersity could be the result of more uniform thickness and a smaller fraction of exposed materials lying outside the effective thickness of the layer. The influence of the thickness of the layer will be discussed below.

Experience has shown that at lower energy electrons requires a bit more surface dose. This may be a consequence of the energy is loss of electrons before entering them into the materials and differences in the profiles according to the dose from the depths for different energies of the electrons. The latter determine the total dose or energy delivered by the electrons.

Table 7

Depolymerization fundamentals agent Apent AT-2001 using different doses
Dose (Mrad)/energy (MeV)Viscosity (CP)The molecular weight at the maximum of the distribution (Mρ)The mass-average molecular mass (Mw)Brednikova molecular mass (Mn)The polydispersity (Mw/Mn)
1/1,23,8003680005040001950002,59
3/1,235163000194000875002,22
6/1,219116000119000562002,12
7/1,213101000110000466002,37
4/3,026of 129,000150000600002,46
5/3,021115000153000600002,55

Example 6 the influence of the thickness of the material irradiated sample (base agent AT-2001) molecular weight is at and polydispersity.

The irradiation was carried out by a dose of 6 mrad at electron energy of 1.2 MeV. This tray was distributed to the different number of samples. After irradiation, the samples were cooled for at least one day, and then analyzed. The viscosity and the molecular weight was determined in the same way as described (see table 8). To achieve narrow polydispersity need to produce radiation in a layer not exceeding the effective thickness to achieve a more homogeneous dose distribution along the path of the beam (the effective thickness of guar at 1.0 MeV is 0.36 cm or 0.25 g/cm2). Figure 5 and 6 clearly shows the influence of sample thickness on the molecular weight and polydispersity, respectively. When the thickness of the layer is not higher than the effective thickness and molecular weight, and polydispersity remains almost constant. However, they exponentially increase with the increase of sample size over the effective thickness. Effective thickness varies depending on the beam energy in MeV.

Table 8

Depolymerization fundamentals agent Apent AT-2001 under the different thickness samples*
Dose (Mrad)Viscosity (CP)The molecular weight at the maximum of the distribution (Mρ)The mass-average molecular mass is (M w)Brednikova molecular mass (Mn)The polydispersity (Mw/Mn)
0,1214116000111000504002,20
0,2815116000119000562002,12
0,3619122000the 125,00056600of 2.21
0,5236126000210000667003,15
0,712,500135000467000891005,24
*irradiation at 1.2 MeV with a surface dose of 6 Mrad

In example 7 the effect of using different batches fundamentals agent AT-2001.

The basis of the agent AT-2001 obtained from the guar resin by hydroxypropylamino in the presence of sodium hydroxide. As the nature of the guar resin and features of the process hydroxypropylamino tend to lead to differences between different batches of the basics of the agent AT-2001. It is known that these differences can alter its reactivity when interacting with hydrogen peroxide, which leads to different levels of depolymerization. However, as shown in example 1,method of exposure according to the present invention leads to depolymerization of guar, powder of guar and hydroxypropylamino to a predetermined molecular weight. In this regard, it was not expected that the differences between the different parties fundamentals agent AT-2001 may cause any noticeable differences in the degree of depolymerization carried out under irradiation. As a test, a dose of 5 Mrad when the thickness of the layer is not greater than the corresponding effective thickness, irradiated four different parties fundamentals agent AT-2001, after which the above-described method measured the viscosity of their solutions. The samples were covered with plastic wrap. When the thickness of the samples changed in the range of 0.76 to 1.27 cm, i.e. less than the effective thickness of the energy in the beam of 2.2 MeV, part of 1.52 cm, the difference in the thickness of the samples was minimized in order to evaluate the differences between different parties. As shown in table 9, the viscosity of the irradiated samples ranged from 11 to 15 JV, i.e. substantially smaller than the experimental error. The average viscosity was 13.4 JV with a standard deviation (n-1) of 1.13. Abnormal depolymerization under irradiation of different parties were not found.

Table 9

Depolymerization of various parties fundamentals agent at-2001*
The batch numberMass, gThickness, cmWescast is, SP 25, 29
N-A3171,2712,8
H0210-071CR297,11,1914.4V
H0210-071AR2971,1915
H0210-997HR1284,41,1412,6
H0210-071DR269,81,0813,6
H0210997HR2701,0814
H0210997HR3201,2813,6
H0210997HR1900,7611,4
*irradiation with a 2.2 MeV

Examples 8-12

In examples 8-12 considered depolymerization fundamentals agent at-2001 during factory testing.

In these examples, the irradiation was carried out at a 2.2 MeV on industrial installation IBA in Gaithersburg. According to obtained data, a dose of 4 Mrad and loading of 0.79 g/cm2i.e. the 14 lb/tray (8000 cm2) are the optimal parameters to obtain a product with a molecular weight of about 200,000 daltons. Loading tray corresponded to the effective thickness of the beam. Studied the effect of radiation dose, the thickness and the party. The results of the tests are summarized in table 10. The samples were weighed on trays, and then distributed and animali manually. Since the mechanical leveling was impossible, there were significant differences in the thickness of the layer. Investigated samples after tests. The viscosity was measured using viscometer Fann 35 after dissolution of 5.55 g of irradiated material together with 1.5 g of monophosphate sodium in water at room temperature. The results are shown in table 9.

Table 10
The number of trialsDose, MradLb/trayThe batch number
1314H0303221AR
2414H0303221AR
3514H0303221AR
4416,5H0303221AR
5411,5H0303221AR
6414H0303192CR
7414H0212269KR
8614H0303221AR

In example 8 considers the measurement of viscosities depolimerizovannogo fundamentals agent AT-2001, obtained in the above test, in time.

The sample after the test 2 (tray number 17, 4 Mrad 14 lb/tray party H0303221AR) took 15 minutes after irradiation. Then he measured its viscosity, which is then also measured after 1.5 hours and 1 day (see table 11). The viscosity of all samples tested, measured within 20 to 90 minutes and 1 day after exposure (see table 12). For some samples, there were significant differences between the values of viscosity, measured immediately (20-90 minutes after irradiation and 1 day later. These differences were probably caused by a rapid decrease in viscosity immediately after irradiation, since the time between irradiation and measurement of the viscosity was different for each sample. Table 12 clearly shows the rapid decline in the characteristic time scale. This result shows that in order to stabilize the viscosity after irradiation requires at least one hour. The following examples were used for this comparison the viscosity measured after one day, if not continued its decline.

Table 11

The change in viscosity over time
Time (h)Viscosity (CP)
0,2547
1,535
2429

In example 9 a sample of the product obtained in the course of you who episunago test 2, were tested for uniformity of foundations agent AT-2001.

In test 2 (4 Mrad, 14 pounds/tray, party H0303221AR) three samples were collected from different zones of the same tray, and three other sample was collected from different trays. Inside the tray and between the various trays were significant differences (see table 12). Provided complete stabilization of the viscosity of the material after one day, the average of three samples from one tray 34.6±12,1, and the average of six samples from four different trays was 33.9±12,0. These discrepancies were caused, most likely, differences in thickness, as will be described in the following example.

Table 12

Viscosity sample
The number of trials1222222456738
The name of the partyAndAndAndAndAndAndAndAndAndInAndAnd
Dose (Mrad)34444 44444455
Weight on one tray (lbs)141414141414
Thickness (cm)1,131,131,131,131,131,131,131,330,931,131,131,131,13
The tray number3578
SampleAndIn
Viscosity172233446444744442624 373418
Viscosity244172643372945402422332719
Viscosity3451826,643,6383047412623342920
1The viscosity was measured within 2 hours after exposure, with a time of hydration of 3 minutes.
2The viscosity was measured within 1 day at the time of hydration for 3 minutes.
3The viscosity was measured within 1 day at the time of hydration 15 minutes.

In example 10 in terms of the viscosity of the product was evaluated the influence of thickness of the irradiated material.

In tests 4 and 5, the radiation dose was 4 Mrad, and the trays were intentionally loaded, respectively, 20% higher and 20% less materials (party H0303221AR). Compared with the average value obtained after test 2, clearly visible trend (see table 13). Because the contents of the tray were not leveled with sufficient thoroughness, most likely, had the seat irradiation beyond the effective thickness even when processing the sample with thickness, which was 20% less effective thickness. The viscosity represents average values.

Table 13

The influence of thickness
The number of trials42 (average values)5
Weight on one tray (lbs)16,51411,5
Thickness (cm)1,331,130,93
Viscosity1444026
Viscosity2403324
Viscosity3413426
1see table 12.
2see table 12.
3see table 12.

In example 11 was evaluated the influence of irradiation dose on the viscosity of the product.

A sample from the same batch (H0303221AR) were irradiated with doses of 3, 4, 5 and 6 Mrad in trials 1, 2, 3, and 8, respectively. Expected decrease of viscosity with increasing dose. The trend is clearly noticeable when compared with the average value obtained in test 2 (see table 14).

Tab the Itza 14

The influence of dose
The number of trials12 (average values)38
Dose (Mrad)3456
Viscosity172403418
Viscosity244332719
Viscosity345342920
1see table 12.
2see table 12.
3see table 12.

In example 12 was evaluated the effect of using different batches fundamentals agent at-2001.

Three different parties, H0303221AR, H0303192CR and H0212269KR were irradiated under the same conditions, ie 4 Mrad and 14 lb/tray. No significant differences in comparison with the average value obtained in test 2, were observed. As it turns out, marked differences were primarily driven by the quality of levelling in the tray and not the differences between the parties (see table 15). When the same dose of viscosity for the three samples ranged from 24 to 45 SP. Because for the same sample were significant differences from 18 to 47 JV (with whom. test 2, part A, 4 Mrad in table 12), the definition of deposits in such differences, caused by the difference of the parties and the influence of sample preparation was difficult.

Table 15

The differences between the various parties
Party nameA (average)In
Viscosity1402437
Viscosity2332233
Viscosity3342334

1see table 12.
2see table 12.
3see table 12.

While some embodiments of the present invention described and/or illustrated by the examples above, from the above disclosure of the invention the experts in this field should be obvious and various other options for its implementation. Thus, the present invention is not limited to the described and/or illustrated by examples variants of implementation of the present invention, but also the implies the possibility of significant changes and modifications without departure from the scope of the claims.

1. The method of depolymerization of polysaccharides selected from the group comprising galactomannan, modified galactomannan and xanthan gum to a given molecular weight, namely, that the polysaccharides are affected by radiation in the form of high-energy electron beams.

2. The method according to claim 1, in which the galactomannan depolymerized to molecular weight less than approximately 700000 Dalton.

3. The method according to claim 1, in which the galactomannan depolymerized to molecular weight less than approximately 500000 Dalton.

4. The method according to claim 1, in which the galactomannan depolymerized to molecular weight less than about 300000 daltons.

5. The method according to claim 3, in which the galactomannan depolymerized to molecular weight between about 100,000 and about 250 ' 000 daltons.

6. The method according to claim 1, in which the galactomannan are present in the material selected from the group comprising guar gum, the endosperm of guar, hydroxypropanoyl, cationic guar, guar from carob, guar from cesalpinia prickly, carboxymethylate, carboxyphenoxypropane, cationic hydroxypropylamino, hydroxyalkylated and carboxylique.

7. Galactomannan obtained according to the method according to claim 1.

8. Galactomannan according to claim 5, selected from the group comprising guar gum, endosperm guar guide is oxypropylene, cationic guar, guar from carob, guar from cesalpinia prickly, carboxymethylate, carboxyphenoxypropane, cationic hydroxypropanoic, hydroxyalkylated and carboxylique.

9. Agent for fracturing in oil wells, including:

a) additive and

b) galactomannan, cross stitching is the additive having a molecular weight between about 100,000 and about 250 ' 000 daltons.

10. Agent for fracturing according to claim 9, in which galactomannan also has a polydispersity below approximately 3.0 and hydrated with not less than 90% within 3 minutes

11. Agent for fracturing according to claim 9, in which the additive for cross-linkage selected from the group comprising borate, titanate or zirconate ORGANOMETALLIC agents for cross-linkage.

12. Agent for fracturing according to claim 9, additionally including proppants.

13. Agent for fracturing in oil wells, including:

a) proppants and

b) galactomannan having a molecular weight between about 100,000 and about 250 ' 000 daltons.

14. Agent for fracturing in oil wells in item 13, in which galactomannan also has a polydispersity below about 30 and hydrated with not less than 90% within 3 minutes

15. Agent for fracturing in oil wells, including:

a) proppants;

b) an additive for cross stitching and

C) galactomannan, cross stitching is the additive having a molecular weight between about 100,000 and almost 250,000 daltons and a polydispersity below approximately 3.0.

16. Agent for fracturing in oil wells, including:

a) proppants;

b) an additive for cross-linkage;

C) galactomannan, cross stitching is the additive having a molecular weight between about 100,000 and about 250 ' 000 daltons, and not less than 90% of the challenge in the hydrated product within 3 minutes



 

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29 cl, 4 tbl, 4 dwg, 5 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to photoinitiating agents of phenylglyoxylic acid order used in polymerizing compositions to be subjected for hardening. Invention describes a photoinitiating agent of the formula (I): wherein Y means (C3-C12)-alkylene, butenylene, butinylene or (C4-C12)-alkylene that are broken by groups -O- or -NR2- and not following in sequence; R1 means a reactive group of the following order: -OH, -SH, -HR3R4, -(CO)-OH, -(CO)-NH2, -SO3H, -C(R5)=CR6R7, oxiranyl, -O-(CO)-NH-R8-NCO and -O-(CO)-R-(CO)-X; R2 means hydrogen atom, (C1-C4)-alkyl, (C2-C4)-hydroxyalkyl; R3 and R4 mean hydrogen atom, (C1-C4)-alkyl, (C2-C4)-hydroxyalkyl; R, R and R mean hydrogen atom or methyl; R8 means linear or branched (C4-C12)-alkylene or phenylene; R9 means linear or branched (C1-C16)-alkylene, -CH=CH-, -CH=CH-CH2-, C6-cycloalkylene, phenylene or naphthylene; X, X1 and X2 mean -OH, Cl, -OCH3 or -OC2H5. Also, invention describes a method for synthesis of a photoinitiating agent, polymerizing composition and substrate covered by its. Proposed photoinitiating agent possesses the effective introducing capacity and absence of migration in thermal treatments.

EFFECT: improved and valuable properties of agent.

13 cl, 1 tbl, 16 ex

FIELD: polymerization catalysts.

SUBSTANCE: invention relates to a method for preparing supported titanium -manganese catalyst for synthesis of super-high molecular weight polyethylene via suspension ethylene polymerization process in hydrocarbon solvent. Titanium-containing catalyst supported by magnesium-containing carrier is prepared by reaction of organomagnesium compound Mg(C6H5)2•nMgCl2•mR2O, where n=0.37-0.7, m=2, R20 represents ether wherein R is i-amyl or n-butyl, with a silicon compound, namely product obtained by reaction of compound R'kSiCl4-k (R' is methyl or phenyl and k=0-1) with silicon tetraethoxide Si(OEt)4 at molar ratio R'kSiCl4-k/Si(OEt)4 = 6 to 40. Ethylene polymerization process in presence of above-defined catalyst in combination with co-catalyst is also described, wherein obtained super-high molecular weight polyethylene has loose density ≥ 0.39 g/cc.

EFFECT: increased molecular weight and loose density of polyethylene.

4 cl, 1 tbl, 8 ex

FIELD: polymer production.

SUBSTANCE: invention relates to high-stereospecific 1-butene (co)polymer and a high-activity process for producing the same. Process comprises polymerization of reactive monomer 1-butene in presence of catalyst including solid component containing titanium compound and in presence of inert gas, the latter being introduced into reactor together with hydrogen in order inert gas to be present in reactor during polymerization. This step is performed at elevated pressure in polymerization reactor owing to use inert gas at higher pressure than equilibrium pressure of gas-liquid reactant system at reaction temperature from 10 to 110°C. High-stereospecific polybutylene obtained in this process is characterized by that it is 1-butene homopolymer or copolymer including up to 40 wt % α-C2-C20-olefins other than 1-butene and shows following properties: titanium does nor present in catalyst residues at the ppm level, stereospecificity expressed through content of isotactic pentads (mmmm%) and measured using 13C-NMR technique equals 96 or higher, and molecular mass distribution (Mw/Mn) is 3-6.

EFFECT: enabled effective process for production of high-stereospecific polybutylene essentially free of catalytic residues.

3 cl, 4 dwg, 11 ex

FIELD: polymer production.

SUBSTANCE: invention relates to high-stereospecific 1-butene (co)polymer and a high-activity process for producing the same. Process comprises polymerization of reactive monomer 1-butene in presence of catalyst including solid component containing titanium compound and in presence of inert gas, the latter being introduced into reactor together with hydrogen in order inert gas to be present in reactor during polymerization. This step is performed at elevated pressure in polymerization reactor owing to use inert gas at higher pressure than equilibrium pressure of gas-liquid reactant system at reaction temperature from 10 to 110°C. High-stereospecific polybutylene obtained in this process is characterized by that it is 1-butene homopolymer or copolymer including up to 40 wt % α-C2-C20-olefins other than 1-butene and shows following properties: titanium does nor present in catalyst residues at the ppm level, stereospecificity expressed through content of isotactic pentads (mmmm%) and measured using 13C-NMR technique equals 96 or higher, and molecular mass distribution (Mw/Mn) is 3-6.

EFFECT: enabled effective process for production of high-stereospecific polybutylene essentially free of catalytic residues.

3 cl, 4 dwg, 11 ex

FIELD: polymer materials.

SUBSTANCE: invention relates to preparation of cellular polymer particles suited to be used in coating deposition compositions. Cellular polyesters-based polymer particle according to invention including spherical particles having numerous air hollows and long-chain aliphatic groups and/or spatially hindered branched-chain hydrophobic groups associated with surface of said spherical particles is proposed. A composition for preparing indicated cellular particles and a method of preparing the same are developed.

EFFECT: enlarged assortment of starting materials for polymeric coating compositions.

11 cl, 10 tbl, 17 ex

FIELD: chemistry of polymers.

SUBSTANCE: invention relates to emulsion method for co-polymerization of acrylic monomers. Invention proposes a method involving preliminary emulsification of mixture of butyl acrylate with (meth)acrylic and/or vinyl monomer in water in the following mass ratio co-monomer : water = 1:(0.2-0.3) in the presence of 3.4-4.0 wt.-% of sulfooxyethylated alkylphenol ammonium salt wherein (C8-C10)-alkyl has the alkylation degree 18-26 wt.-%, the following emulsion co-polymerization at temperature 78-82°C for 3-10 h at continuous dosing of preliminary prepared co-monomers emulsion and 0.3-0.6 wt.-% of ammonium or potassium persulfate in the total ratio to the reaction mass co-monomer : water = 1:(0.4-0.5) followed by additional polymerization of the reaction mixture in addition of 0.1 wt.-% of ammonium or potassium persulfate after keeping the reaction mixture for 0.5 and 1.5 h and its final temperature keeping for 2 h. Invention provides increasing concentration of acrylic copolymer aqueous dispersion at low content of coagulum and improving its adhesion properties. Invention provides the development of a method for preparing highly concentrated aqueous dispersion with the content of acrylic copolymer 60 wt.-%, not less, for glues showing sensitivity to pressure.

EFFECT: improved preparing method, improved and valuable properties of dispersion.

2 cl, 1 tbl, 13 ex

FIELD: chemistry of polymers, chemical technology.

SUBSTANCE: invention relates to technology for producing granules used in preparing ion-exchange resins. Invention describes a method for producing polymeric monodispersed particles by suspension polymerization and involves the following steps: preparing monodispersed drops by adding a drop-forming device for preparing an aqueous dispersion medium into a chamber that formed the continuous phase, ejection of monomer hydrophobic liquid to aqueous dispersion medium through draw plate holes up under effect of regular vibration to form monomer liquid drops of a equal size preferably in aqueous dispersion medium; carrying out preliminary polymerization by adding prepared monomer liquid drops in aqueous dispersion medium into the first reactor, carrying out the polymerization reaction in a quasi-liquid layer to prepared suspension of partially polymerized drops of monomer in aqueous dispersion medium to degree when drops can't fuse or break; carrying out the final suspension polymerization at intensive stirring in the second reactor; at step for preparing monodispersed drops an aqueous dispersion medium is added to the form-forming device chamber at temperature 60-90°C, and monomer hydrophobic liquid is added into the drop-forming device at temperature 5-25°C or at environment temperature. Invention provides expanding zone for monodispersing drops of hydrophobic monomeric liquid in the drop-forming device allowing to vary sizes of prepared monodrops, and technical and technological simplifying the unit device.

EFFECT: improved producing method.

13 cl, 7 dwg, 1 ex

FIELD: food industry; oat enzymatic treatment.

SUBSTANCE: using this method it is possible to obtain new improved oat products containing modified starch, the products have increased glucose and β-glucan content. The present invention is also related to the food products and food compositions, including oat with modified starch or oat liquid containing modified starch.

EFFECT: use of enzymes at their optimal temperatures; efficiency and effectiveness.

24 cl, 1 dwg, 1 tbl, 3 ex

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