Articles comprising fibers and/or fibrids, fibers and fibrids, and method for producing the same

FIELD: processes for producing of fibers, fibrids and articles from said fibers and fibrids, in particular, non-woven products, paper, and may be used for manufacture of electric insulation.

SUBSTANCE: articles are reinforced with fibers and/or fibrids produced from mixture of thermally stable polymers - aromatic polyamides, aromatic polyamide-imide resins or polyimide resins and thermoplastic polymers - polysulfides, polysulfones. Method involves reinforcing articles by thermal pressing at temperature exceeding glass transition temperature of thermoplastic polymer.

EFFECT: improved mechanical properties and air permeability and high processability.

23 cl, 2 dwg, 7 tbl, 20 ex

 

The present invention relates, in particular, to new products, particularly to nonwoven products containing fibers and/or fibrid. It also applies to the new fibers and fibrids, as well as to a method for producing these fibers and fibrin.

In particular, in the production of electrical insulation seek to obtain products having a high resistance to fluctuations in temperature and good mechanical and/or dielectric properties. These products can, for example, be a non-woven products, obtained from heat-resistant fibers. To obtain good mechanical properties of the product, you need a good grip heat-resistant fibers; in addition, to obtain a good dielectric properties, the product must have a uniform and dense structure. With this aim, strive to obtain good adhesion of the heat-resistant fibers in the product. In addition, the product tend to get a homogeneous and dense structure. These products depending on their structure (in particular, their density and/or composition can be used to reinforce the mechanical properties and/or as a dielectric.

In U.S. patent 2999788 proposed, for example, to obtain particles of synthetic polymers or fibrid"having a special structure, which is applied together with the fibers on the basis of synthetic polymers, with the aim in the teachings woven fibrous structures according to the method of producing paper. For these patterns, you can exert pressure at high temperature, resulting in a yield of hibrido. However, obtaining such hibrido by deposition under conditions of shear deformation is complex and expensive. However, for direct use these fibrid must remain in the aquatic environment. In this regard, they may not be highlighted, and not easy to transport, which limits their use.

In French patent 2163383 encouraged to obtain non-woven products, consisting of a layer of fibers on the basis of refractory material or having a melting point of more than 180°With fibre interconnected with polyamide-amidnogo binder that is used in proportions of from 5 to 150% by weight used dry fibers. However, the impregnation of the resin is carried out in solution in a solvent, which leads to adverse consequences affecting the properties of nonwoven products.

To improve the processability of non-woven layers in the French patent it is proposed to obtain the wet non-woven layers of fibers consisting of refractory material or having a melting point of more than 180°connected powdered thermoplastic polymer.

If these layers can theoretically be carried out by the method used is La receipt paper in practice their industrial reception is complex: it is really a mixture of synthetic fiber - binder resin is too low adhesion during processing and, in particular, such a mixture does not have sufficient adhesion so that it was possible to have a dynamic way, for example, on the installation for commercial receipt paper; such layers can be obtained, mainly in laboratory settings type "Formette Franck", i.e. a static way and private parties, as outlined in the examples.

In French patent 2685363 serves to receive the wet paper composed of fibers having a thermal stability greater or equal to 180°With which are interconnected using fiber binder and a chemical binder.

Use a binder to ensure adhesion of the fibers, for example, non-woven products leads, in particular, to the difficulties and costs when using these binders.

The present invention offers new products, in particular, non-woven products, do not have the above disadvantages, which contain fiber and/or fibrid. The present invention also provides new fiber and fibrid and method for producing these fibers and hibrido, as well as products obtained from these fibers and hibrido, for example ekanya products. Thermoplastic portion of the fiber or fibrid of the present invention plays, in particular, the role of chemical binders, as described earlier. She, in particular, tends to "soak" without the influence of pressure and temperature. Thus, it appears grip heat-resistant fibers in these products, with good thermal and mechanical properties. These products can have a uniform and dense structure, and, therefore, have good dielectric properties.

With this purpose, a first object of the present invention relates to a product containing at least fiber and/or fibrid, characterized in that the fibers or fibrid form of a mixture of polymers containing at least one heat-resistant polymer and one thermoplastic polymer chosen from the group of polysulfides and polysulfones.

The second object of the present invention relates to the aforementioned fiber and fibrid and the way they are received.

As the third object of the present invention provides the use of the above products for the manufacture of electrical insulation.

Heat-resistant polymer of the present invention is, preferably, refractory or has a glass transition temperature in excess of 180°S, preferably equal to or greater than 230°s or greater. Those who Mosconi polymer of the present invention has a thermal resistance (i.e., in particular, is able to retain its physical properties over a long period of time at temperatures over 180°C. the Specified heat-resistant polymer is chosen, preferably, from polyaramide and polyimides. As an example polyaramide can lead aromatic polyamides, such as a polymer, having a brand name Nomex®or kidnie polyamides, such as polymer, known under the brand name Kermel®. As an example, polyimides, you can lead the polyimides obtained in accordance with European application 0119185, known under the brand name R®. Aromatic polyamides may be the polyamides described in European application 0360707. They can be obtained in accordance with the method described in European application 0360707.

thermoplastic polymer is selected from the group of polysulfides and polysulfones. As an example of the polysulfide can lead to the polyster, denoted hereinafter referred to as PPS. As an example of polysulfones, hereinafter referred to as PSU, we can give simple polyethersulfone, denoted hereinafter as PESU or polyphenylsulfone, denoted hereinafter as PPSU.

These thermoplastic polymers have a glass transition temperature less than or equal to 250°that allows them, in particular, to play the role of a chemical binder in the h is x according to the present invention and "absorbed" without the influence of pressure and temperature. These polymers also have good heat resistance, because they belong to a thermal class (thermal index) over 130°C. This provides advantages in obtaining products with good heat resistance.

In accordance with the preferred method of implementing the present invention, a thermoplastic polymer and a heat-resistant polymer soluble in the same solvent. Preferably, the solvent is a polar aprotic solvent. It preferably selected from DMEU, DMAC, NMP (N-organic), DMF (DMF).

Preferably, the fiber or fibre of the present invention contains at least 10 wt.% thermoplastic polymer.

Fibrid are small in the form of fibrous particles or have the form of thin films that are not hard. Two of their three spatial dimensions are of the order of several microns. Their small size and their flexibility allows you to place them in a physically twisted configuration, similar to that found in the present paper formed from the pulp.

The fiber of the present invention has, preferably, a titer in the range from 0.5 dtex and 13.2 decitex. The fiber of the present invention has preferably a length in the range from 1 to 100 mm

The fiber of the present invention MoE is et to have a different shaped cross-section, for example, round, three-bladed, flat. Under the fiber-shaped cross-section to understand the fiber, the ratio of length/width of which is greater than or equal to 2.

Fiber or fibre of the present invention can be processed with a binder composition.

In accordance with the preferred method of implementing the articles of the present invention is a fiber obtained by mixing a heat-resistant polymer and thermoplastic polymer further forming the threads of the mixture.

Mixing the two polymers can be applied by any method known to the expert. Preferably, the polymer mixture obtained by dissolution of the polymer, at least, in the same solvent. A thermoplastic polymer and a heat-resistant polymer can be dissolved together, simultaneously or sequentially in a solvent or mixture of solvents that can be mixed with each other, for example, in one reactor. The polymers can be dissolved separately in the same solvent or different solvents that can be mixed with each other, for example, in two different containers, and then the polymer solutions combine.

Conditions of dissolution such as temperature, determined by the expert, depending on the type of polymers used(s) solvent(s). To facilitate dissolution, his mo is but for example, to perform at a high temperature and under stirring.

The dissolution can be carried out at room temperature. Preferably, the temperature of dissolution ranges from 50 to 150°C.

The solvent(s) when the dissolution is preferably a polar aprotic solvent. You can use dimethylethylenediamine, for example, dimethylethylenediamine (DMEU) or dimethylpropyleneurea. The solvent is preferably selected from DMEU, dimethylacetamide (DMAC), N-methylpyrrolidone (NMP), dimethylformamide (DMF). The solvent in the dissolution may be a mixture of polar aprotic solvents, for example a mixture of dimethylethanolamine and anhydrous polar aprotic solvent, such as NMP, DMAC, DMF, tetramethylrhodamine or γ-butyrolactone.

The solution of the polymer obtained after dissolution, called collodion. The resulting solution is preferably transparent.

The total mass concentration of the polymer in relation to the solution preferably is in the range from 5 to 40%.

The solution may also contain additives such as pigments, amplifiers patterns, stabilizers, matting compounds.

The solution must also have a viscosity that allows you to mould the thread, which is usually from 100 to 1000 P. For wet spinning viscosity, preferably is, component in the range from 400 to 800 CPS, measured using a viscometer, with a brand name EPPRECHT RHEOMAT 15. For dry spinning viscosity preferably is in the range from 1500 to 3000 P.

Mixing polymers can also be sequentially one after the other at the stage of spinning, for example, sequential injection of each polymer is soluble or insoluble in the solvent during the spinning process.

In the framework of the present invention can use any known specialist spinning method from a mixture of polymers, in particular, from a solution of polymers.

As an example, dry spinning, in accordance with which a solution of polymer (fibrous substance in the form of a solution) ekstragiruyut through the capillaries in an environment conducive to the removal of solvent, for example, in the evaporator medium, the temperature of which is supported close to or higher than the boiling point of the solvent, giving the opportunity to carry out the solidified filament fibers. At the outlet of the evaporation chamber filament fibers freed from residual solvent. For this purpose, they can be rinsed with water, possibly with the boiling temperature and under pressure, and dried in the usual way, preferably at a temperature of more than 80°C. They can also be thermally processed at a temperature greater is whether equal 160° With under reduced pressure and/or in an inert atmosphere. After the release of residual solvent filament fiber is pulled, for example, at a temperature of more than 250°With, preferably, more than 300°With, preferably, in the absence of oxygen.

In accordance with a preferred embodiment of the present invention as a spinning method used wet spinning, in accordance with which a solution of polymer (solution fibrous substances) ekstragiruyut in the coagulation bath.

The temperature of the solution during the spinning may vary within wide limits depending on solution viscosity for spinning. For example, a solution having a low viscosity, easy to ekstradiroval at ordinary temperature, while a solution with high viscosity is desirable to ekstradiroval at high temperature, for example, at 120°With or even higher, in order to avoid the use of high pressure in filiere. The solution for spinning is preferably support at a temperature in the range from 15 to 40°C, preferably from 15 to 25°C.

Coagulation bath used in the method according to the present invention preferably is an aqueous solution containing from 30 to 80 wt.%, preferably, from 40 to 70 wt.% the solvent or solvent mixture, preferably, dimethylaniline the ins (DMAU) or DMF or mixtures thereof, although it is often preferable to use a bath containing more than 50 wt.% solvent, to obtain a filament fibers with the best vitiagivaet, and therefore, with the best result properties.

Preferably, the polymer solution for spinning was close to the rate of coagulation.

The speed of spinning the coagulation bath may vary within wide limits depending on the solvent concentration and distance when moving filament fibers in said tub. The speed of spinning in the coagulation bath can easily be selected, for example, in the range from 10 to 60 m/min, although there may be achieved a higher speed. Spinning at lower speeds does not benefit from the profitability of the process. In addition, too high speed spinning in a coagulation bath to reduce vitiagivaet filament fibers in the air. Thus, the speed of spinning in the coagulation bath is chosen, taking into account both profitability and the desired target filament fiber.

Then filament fibers emerging from the coagulation bath in the gel state, is pulled, for example, in the air, as a percentage, determined by the ratio (V2/V1)·100, while V2 is the speed of the cylinder pulling, V1 is the speed of you who asknih cylinders. The degree of stretching of the filaments in the gel state exceeds 100%, preferably, is greater than or equal to 110% or even higher, for example greater than or equal to 200%.

After extrusion, preferably air, which is usually carried out by passing between the two series of cylinders, from filament fibers remove residual solvent by known methods, typically by washing with water, which is circulated counter-current, or wash the cylinders, preferably at room temperature.

In accordance with another preferred method of implementing the present invention method is spinning, dry spinning.

Two methods of spinning, as described previously (dry spinning and wet spinning) the washed filament fibers are then dried by known methods, for example, in the dryer or on the cylinders. The specified temperature of drying may vary within wide limits, as well as speed, which is higher than the above temperature. Usually advantage provides drying with a gradual increase of temperature, thus the specified temperature can reach and even exceed 200°C.

Further filament fibers may be subjected to intense stretching at a high temperature, with the aim of improving their mechanical properties and, in particular, their tensile strength that can show the change important factor for some applications.

Specified reinforced extrusion at high temperature can be accomplished in any known manner: in the oven, on the plate on the cylinder, the cylinder and the plate, preferably in a closed chamber. It is carried out at a temperature equal to at least 150°With which may reach 200 to 300°and even higher. The degree of stretching is usually at least 150%, but it can vary within wide limits depending on the desired characteristics of the target thread. Thus, the overall degree of stretching is at least 250%, preferably at least 260%.

The totality of ways of stretching and possibly reinforced extrusion can be performed in one or several stages, in a continuous way or by individual parties in combination with the previous operations. In addition, increased extrusion can be combined with drying. It is enough at the end of drying to provide the area with high temperature, which allows increased stretching.

Next, the resulting filament fiber is cut in the form of fibers in accordance with well-known specialist way.

In accordance with another way of making products according to the present invention fibrid obtained by mixing a heat-resistant polymer and a thermoplastic polymer, with subsequent deposition of CME and under the influence of shear stress.

Mixing a heat-resistant polymer and thermoplastic polymer can be accomplished in a manner analogous to the method described previously for fibers.

Fibrid of the present invention can be obtained, in particular, deposition of a solution of the polymer in the device for hibridization, which is described in U.S. patent 3018091, where the polymer is cut in the deposition process.

In accordance with the preferred method of implementing the present invention, products are non-woven products. Nonwoven products are in the form of sheets, films, felt, and usually they mean any interlaced fibrous structure obtained without applying any of the operations of textile production, such as spinning, knitting, weaving.

The product can be obtained from one type of fiber or, conversely, from a mixture of fibers. Non-woven product according to the present invention contains at least partially of fibers and/or fibrid of the present invention. The product of the present invention may contain fibers of different types and/or fibrid different types. In addition to the fibers and/or hibrido of the present invention a non-woven product may contain, for example, fibers and/or heat-resistant fibrid or hardening fibrid para-aramid, meta-aramid, polyamide-amidnogo type, etc.

Non-woven product may contain the, for example, the fibers of the present invention and a heat-resistant fiber. When the product contains fibrid, the product may, for example, contain fiber according to the present invention and hybridi heat-resistant polymer in accordance with a first method embodiment of the invention; or the product may, for example, contain heat-resistant fiber and fibrid of the present invention, in accordance with another method embodiment of the invention.

Non-woven product according to the present invention can be obtained by the method and with the use of the plant for producing non-woven products, well-known specialist. The product of the present invention are usually obtained by applying a phase of "layers", i.e. the stage of distribution of fibers and/or hibrido on the surface, the next stage of "consolidation" of the structure obtained.

In accordance with the preferred method of implementation of the present invention the stage of "layering" carried out "dry way" ("drylaid"), such as, in particular, of the fibers of the present invention, the length of which ranges from 40 to 80 mm Fiber can be, for example, processed using a conventional machine to sharpen wool.

In accordance with a preferred method according to the present invention the stage of "layering" carried out "wet way" or "getting paper" ("wetlaid"). The fiber used is passed to the specified method implementation usually have a length in the range from 2 to 12 mm, preferably from 3 to 7 mm, and their titer, expressed in decitex, is usually in the range from 0.5 to 20. It is theoretically possible to use a fiber length of more than 12 mm, but in practice, longer fibers entangled, requiring more water, which complicates the process.

In accordance with the method of implementation of the non-woven product is produced by introduction into water of different components products: fibers and fibrous binder consisting of pulp based on synthetic polymer with thermal resistance equal to 180°or more (such as para-aramid pulp) and/or hibrido based on synthetic polymer having a heat resistance greater than or equal to 180°and/or hibrido of the present invention and possibly other required dispersant, additives or fillers.

The pulp on the basis of a synthetic polymer with thermal resistance equal to 180°or more usually produced from fibers of usual length, in particular, fibrils, in a known manner, to give her a larger number of points of adhesion and increase its specific surface. Among synthetic fibers fibrillation can be subjected only fibers with a high degree of crystallinity. This option corresponds to the fully aromati the definition of the polyamides of polyesters, and other polymers with a high degree of crystallinity is divided in accordance with the axis of the fibers or fibrillated.

To improve certain qualities excipients, additives or fillers can also be used in various proportions depending on the desired properties; for example, you can enter mica to improve the dielectric properties of the product.

Obtaining nonwoven products "method of obtaining paper known to specialists in this field of technology.

The stage of "consolidation" of the structure obtained by layering, which is described previously can be carried out in accordance with the method known in the art. Preferably, "consolidation" is carried out thermally, for example by thermal molding the product. The temperature of thermal pressing is usually higher than the glass transition temperature of the fibers and/or hibrido thermoplastic polymer according to the present invention contained in the product. Preferably, the temperature of thermal pressing is in the range between the glass transition temperature and the softening temperature of thermoplastic polymer.

In accordance with the preferred method of implementation of the present invention the temperature of thermal pressing is in the range from 200 to 350°C. Preferably, the pressure is greater than or equal to 5 bar.

The decree is Noah pressing provides the compaction and consolidation of the product according to the present invention. Usually it is accompanied by the fluidity of thermoplastic polymer fibers and/or hibrido of the present invention contained and distributed throughout the product structure.

The use of thermal pressing is not the only embodiment of the invention. You can use any method of thermal pressing a non-woven products.

Pressing, for example, be performed using a press or a calender with heated rolls. You can make multiple passes through the device for pressing in such a way as to give the desired product density.

The preferred method of thermal pressing is calendering.

In accordance with the preferred method of implementing the present invention, thermal pressing is performed using a continuous press.

Products obtained by extrusion, diverse and differ from each other depending on the conditions of thermal pressing, in particular, temperature, pressure, and time pressing, and depending on the composition of the product, in particular, the number of fibers and/or hibrido of the present invention contained in the product, and the amount of thermoplastic polymer present in these fibers and/or fibretech.

The choice of these parameters Khujand who are depending on the type of products and properties required for the specified product.

Products of the present invention can be used, in particular, in the field of electrical insulation.

The purpose of the products varies depending on their density and, consequently, depending on their properties such as hardness and dielectric properties. They can, for example, be used as insulating material in which the main insulator is oil or resin, such as a mechanical separator" or "power" when placing it between two objects to their electrical insulation. Products can also be used directly as an insulator in the insulation systems of the type "dry" insulators.

The present invention also relates to fiber, characterized in that it is formed from a mixture of polymers containing at least one heat-resistant polymer and one thermoplastic polymer chosen from the group of polysulfides and polysulfones, and the fiber has a titer of less than or equal to 13.2 decitex.

The present invention also relates to hibrido, characterized in that it is formed from a mixture of polymers containing at least one heat-resistant polymer and one thermoplastic polymer chosen from the group of polysulfides and polysulfones.

The above information relating to the heat-resistant polymer is a thermoplastic polymer, fibers and fibrids of the present invention, the method of production of fibers and method of producing hibrido, applicable by analogy to the fibers and fibrids of the present invention.

In accordance with the third object, the present invention relates to the use of the products of the present invention described above, in the field of electrical insulation.

Other features and advantages of the present invention will become more apparent when considering the following examples.

EXAMPLES

Examples 1-3: the mixture of thermoplastic polymer/heat-resistant polymer

Example 1:

In the heated reactor under stirring placed 180 kg of solvent DMEU. First, the specified solvent is heated to a temperature in the range from 60°to 120°C. the Polymer PESU (molecular weight, MW, from 80000 to 90000 g/mol) in the form of scaly granules are placed in a heated solvent 10 equal fractions. The required time between the loading of each fraction depends on the intensity of mixing and temperature. The polymer is injected as long as his number will not be from 20 to 40 wt.% of the mixture.

The percentage of polymer in the mixture affects its viscosity. As an example, when 21% viscosity at 25°350 P; 28% viscosity 460 P.

The mixture of thermoplastic polymer PESU with polyamide-imide Kermel® g is tovat at high temperature, in the interval from 60 to 120°as previously described, from a mixture containing PESU and the solution with 21 wt.% polyamide-imide Kermel® solvent DMEU (MW 150000 g/mol equiv. Polystyrene, viscosity: 600 poises at 25°). The proportion of the two fluids in the mixture expressed as proportions of the polymer PESU in dry matter, ranging from 40 to 60%.

Example 2:

The mixture of the polyamide-imide Kermel®/PESU is obtained directly by dissolving the polymer PESU in solution with 13 wt.% polyamide-imide Kermel® solvent DMEU in the plant for mixing with a high gradient of the shear and a high degree of recycling.

Example 3:

A mixture containing PESU receive in accordance with the working method of example 1. Blend with polyamide-imide Kermel® (in the form of a solution with 21 wt.% polyamide-imide Kermel® solvent DMEU) get in the spinning process joint injection of two fluids in a common duct in the upper part of the static smesiteli placed in the specified pipeline, which supplies the spinning machine. Controlling the proportions of the two fluids in the mixture to control the speed of rotation of the volumetric pump.

Example 4 and 5: Spinning blends of thermoplastic polymer/heat-resistant polymer

Example 4:

The mixture PESU/polyamide-imide Kermel® examples 1 through 3 is spun in accordance with the method of wet spinning. The proportion of polymer PESU is 40 wt.%. Results the following conditions are present as an example of parameters used spinning:

Die with 10,000 holes size of 50 microns

Coagulation bath to 55% solvent, 19°

The speed of spinning of 14 m/min

The degree of stretching: 2X

The destination received the title; 4,4 decitex

The fiber is dried, frizz (give hairiness) and cut in normal conditions (fiber length =60 mm).

Example 5:

The mixture PESU/polyamide-imide Kermel® examples 1 through 3 is spun in accordance with the method of wet spinning. The proportion of polymer PESU is 50 wt.%. The following terms are example parameters used spinning:

Die with 10,000 holes the size of 40 microns

Coagulation bath with 60% solvent, 19°

The speed of spinning of 14 m/min

The degree of stretching: 2X

The destination received the title; 2.2 decitex

The fiber is dried under normal conditions. Giving hairiness and slicing occurs under normal conditions.

Examples 6 through 8: jewelry

Non-woven products in various formats derived from the fibers of example 4 "dry method" and "consolidation" (brushing, layering, calendering) in accordance with well-known specialists of the way.

Use the following material:

The card type Garnett® parallel output

Nakivale Asselin®

The calender KTM®

Table 1 shows the used operating conditions and characteristics of the obtained products.

Mechanical properties of the, such as tensile strength and elongation at break, measured according to standard NF-EN 29073-3, December 1992. The thickness of the products is measured by using a micrometer type Palmer®.

Table 1
ExamplesExample 6Example 7(*)Example 8
Speed calendering (m/min)555
Temperature calendering (°)250250270
Pressure calendering (bar)666
Format (g/m2)426065
Thickness (µm)506570
Density (g/cm3)0,840,920,93
Tensile strength, measured by car (N/5 cm)20,24160,9
Elongation at break, measured by car (%)1,42,12,9
(*) the product from example 7 is subjected to the two-stage calendering.

After calendering determining the magnitude of the yield strength and density.

On phila photograph of the surface of the product from example 8 after calendering.

Figure 2 presents a photograph of the cross-section of the product from example 8 after calendering.

Examples 9 through 12: Getting hibrido from a mixture of thermoplastic polymer/heat-resistant polymer

The mixture PESU/polyamide-imide Kermel® in example 1, diluted DMEU to obtain the desired concentration of polymer PESU/polyamide-imide Kermel®, precipitated with strong shear in accordance with the method described in the patent in France, No. 1214126 or U.S. No. 4187143 in water coagulation bath containing a specified concentration of the solvent DMEU. Table 2 shows the conditions for hibrido.

Table 2
ExamplesThe proportion PESU/polyamide-imide Kermel® (wt.%) before depositionThe proportion of solvent in the coagulation bath (wt.%)
99,525
101550
119,50
129,550

Characteristics of hibrido measure on the unit MORFI (conventional apparatus for measuring paper pulp fibers). Table 3 shows these characteristics.

Table 3
Examples9101112
Length (mm)0,3150,4310,3510,289
Width (µm)40,244,649,730,3
Thin items (% of length)19,511,014,724,9
The percentage of subtle elements (% surface)1,60,40,63,6

Examples 13 to 16: the Product obtained from hibrido

Fibrid in examples 9 to 12 are mixed in equal quantities with the fibers of the polyamide-imide Kermel® length 6 mm These four examples is used for securities on molding apparatus of the type FRANK in the wet and in accordance with the classical method of obtaining paper. The calculated density of the samples is 80 g/m2. Characteristics of the securities are shown in table 4.

The degree of retention is determined as follows:

The degree of retention (%)=(1-[(put mass (g) mass after passing (g))/put weight (g)]·100

Table 4
ExamplesFibridThickness in mmMass, placed in the set is the Weight after completing the installation (g)The extent of holding (%)The mass of a unit area of paper (g/m2)Shops (cm3/g)
13PR199,62,5062,44898772,6
14PR238,82,5162,47898812,9
15Proverbs 11199,52,5172,34293742,7
16PR191,32,5252,50099772,5

Samples of the paper after drying differ in their mechanical properties (table 5) air permeability apparatus BENDTSEN under pressure of 1.47 kPa (table 6) in accordance with the traditional methods used in the paper industry.

Table 5

Mechanical resistance of securities
Examples13141516
Power break (N)1,782,371,053,23
11915870216
The resistance index (tensile strength (Nm/g)1,551,950,942,84
Elongation at break (%)1,892,611,162,09
The modulus of elasticity (MPa)558370638632
Gap (mn)82016005601400
The gap index (Nm/g)with 3.276,072,325,6

Table 6

Breathability
Examples13141516
Averagea 50.558,7876,81,4
The standard deviationa 4.9124,90,2

Examples 17 to 24: Products obtained from hibrido pressing at high temperature

Sample paper for examples 13 through 16 are pressed at high temperature on a laboratory press disks at a temperature of 280°With:

any 10 min at a pressure of 100 bar

any 5 min PR is the pressure of 200 bar

Table 7

The thickness of the specimens pressed paper
Pressure 100 barExamples17181920
ProductPRPRPRPR
The average thickness (μm)for 125.8137,3125,7121,5
Shops (cm3/g)1,631,691,69of 1.57
Pressure 200 barExamples21222324
ProductPRPRPRPR
The average thickness (μm)123,1122116,4121,4
Shops in cm3/g1,591,50of 1.571,58

1. The method of obtaining products, reinforced with fibers, which product contains at least fiber and/or fibrid, formed from a mixture of polymers which comprises at least one heat-resistant polymer selected from aromatic polyamides, aromatic polyamideimide is or polyimides, and one thermoplastic polymer selected from the group of polysulfides and polysulfones, and the strengthening of the specified products reach thermal pressing at a temperature above the glass transition temperature of the specified thermoplastic polymer.

2. The method according to claim 1, characterized in that thermoplastic polymer is chosen from simple polyethersulfone or polyphenylsulfone.

3. The method according to any of claim 1 or 2, characterized in that thermoplastic polymer and heat-resistant polymer soluble in the same solvent.

4. The method according to any of claim 1 or 2, characterized in that the polymer mixture contains at least 10 wt.% thermoplastic polymer.

5. The method according to claim 1, characterized in that the fiber is produced by mixing a heat-resistant polymer and a thermoplastic polymer, and then spinning the mixture.

6. The method according to claim 5, characterized in that the mixture obtained by dissolution of the polymer in the solvent.

7. The method according to claim 6, characterized in that the solvent used polar aprotic solvent.

8. The method according to claim 7, characterized in that the solvent is chosen from dimethylethylenediamine - DMEU, dimethylacetamide - DMAC, N-methylpyrrolidone - NMP, DMF (dimethylformamide) - DMF.

9. The method according to any of pp.5-7, characterized in that the method is spinning wet spinning.

10. The method according to any of pp.5-7, the tives such as those that method is spinning, dry spinning.

11. The method according to claim 1, characterized in that fibrid obtained by mixing a heat-resistant polymer and a thermoplastic polymer with subsequent deposition of the mixture under the influence of shear stress.

12. The method according to any one of claims 1, 5 or 11, characterized in that the product is non-woven product or a paper.

13. The method according to any one of claims 1, 5 or 11, characterized in that thermal pressing is carried out at pressures and temperatures that cause thermal fluidity of at least one thermoplastic polymer.

14. The method according to item 13, wherein during the heat-pressing temperature is between the glass transition temperature and the softening temperature of thermoplastic polymer.

15. The method according to item 13, wherein during the heat-pressing temperature is in the range from 200 to 350°and a pressure greater than or equal to 5 bar.

16. The method according to item 15, wherein the product is a woven product, and heat-pressing is carried out at least one passage through the calender pressure of 6 bar and a temperature in the range from 250 to 280°C.

17. The method according to item 15, wherein the product is paper, and heat-pressing is carried out at least one passage through the calender is a pressure in the range from 100 to 200 bar and a temperature of 280° C.

18. The method according to claim 1, characterized in that the proportion of thermoplastic polymer in the fibers or fibretech is in the range from 40 to 60%.

19. The method according to claim 1, wherein the product further comprises fibers and/or heat-resistant fibrid, in particular para-aramid, methanamine or polyamidimide fiber.

20. The method according to claim 1, characterized in that the fibers have a titer of less than or equal to 13.2 decitex.

21. Fibre used in the method according to one of claims 1 to 20, formed from a mixture of polymers containing at least one heat-resistant polymer selected from aromatic polyamides, aromatic polyamideimide or polyimides and one thermoplastic polymer chosen from the group of polysulfides and polysulfones.

22. The product obtained by the method according to any one of claims 1 to 20, as electrical insulation.

23. The application of item 22, wherein the product further comprises mica.



 

Same patents:
Insulating sheath // 2270489

FIELD: electric insulation engineering; insulating sheaths possessing fire and heat resistance and screening effect.

SUBSTANCE: proposed insulating sheath characterized in high resistance to open flame, high temperatures up to 600 °C, acids, oil products, organic solvents, and microbiological impacts is made of threads having different composition and twisted together; one of threads is made of arimide fiber and functions as reinforcing warp, and other one is made in the form of metal thread, more than 0.018 and less than 0.020 mm thick, that functions as shielding component. Coated or non-coated metal wire is used as shielding component. Reinforcing warp can be made in the form of harness of at least two arimide threads twisted together or it may have a few pairs of arimide fiber threads and metal thread twisted together; these pairs are interwoven to form ribbon or cloth.

EFFECT: enhanced fire resistance and flexibility, reduced weight of insulating sheath.

5 cl, 1 tbl

FIELD: electrical engineering; insulating materials.

SUBSTANCE: proposed method for manufacturing insulating materials used in insulators and surge limiters, as well as in manufacturing pipelines, bushes, shells, bearings, wiring insulation of cases includes some additional operations; pre-drying, impregnation, and final drying of prepreg are effected in vacuum chamber and arbor is preheated before prepreg rolling up. Electric strength of prepreg produced by this method is 3.7 to 4.5 kV/mm which is much higher than that of known tubular prepregs.

EFFECT: enhanced quality of fabric surface pre-treatment, improved conditions of impregnation process.

1 cl

The invention relates to the production of protective and anticorrosive materials obtained by impregnating a fabric base is antiseptic and anti-corrosion compounds and are designed to protect cables

Insulating sheath // 2153723
The invention relates to electrical insulating shells with actuator shielding effect

Insulation coating // 2153722
The invention relates to insulating materials to synthetic, and more precisely to the materials used in insulating technology, and electric machines and apparatus as slot insulation of various gaskets and t
Insulating prepreg // 2084030
The invention relates to electrical engineering materials, namely, pre-impregnated materials (prepregs), intended for the insulation of electrical equipment

The invention relates to a process of manufacturing a multilayer insulating materials of fiber-based heat-resistant aromatic polymers and can be used in the pulp and paper industry

FIELD: production of thermally- and fire-resistant textile materials, in particular, materials produced from mixture of thermally stable synthetic fiber and oxidized polyacrylonitrile fiber, which may be used for manufacture of protective clothing for rescuers, servicemen, firemen, oil industry workers, and gas industry workers, filtering fabrics for cleaning of hot gases from toxic dust in metallurgical, cement and other branches of industry, decorative materials, thermally-resistant isolation, and toxic asbestos substitutes.

SUBSTANCE: method involves mixing non-oxidized polyacrylonitrile fiber with thermally stable synthetic fiber in the ratio of from 30/70 to 80/20, respectively; subjecting resulting mixture in the form of yarn, tape, fabric to thermally oxidizing processing at temperature of 240-310 C during 10-180 min.

EFFECT: elimination of problems connected with textile processing of frangible oxidized polyacrylonitrile fibers owing to employment of elastic polyacrylonitrile fibers rather than such oxidized fibers.

2 cl, 7 tbl, 6 ex

FIELD: polymer materials.

SUBSTANCE: invention relates to technology of manufacturing thermoplastic monofilaments and can be used in fabrication of bristle used under high humidity conditions. Monofilament is composed of polymer blend constituted by at least one polyamide and at least one thermoplastic polyester. Ratio of constituents in the blend is selected according to technical and functional properties determined, on one hand, by destination of bristle and, on the other hand, by environmental conditions in the bristle application location. Polyamide fraction ranges from 10 to 30% and that of polyester from 70 to 90%. Bristle completely meets functional and technical requirements as well as environmental conditions.

EFFECT: reduced manufacturing cost.

16 cl

FIELD: production of electric conducting pulp for manufacture of paper, reinforcing polymer materials and packaging films.

SUBSTANCE: pulp contains fibrous particles including 65-95 mass-% of para-amide and 5-35 mass-% of sulfonated polyaniline containing sulfur in the amount of 8.5-15 mass-% which is dispersed over entire para-amide partially covering the particles externally. Specific area of surface of fibrous particles exceeds 7.5 m2/g. Pulp may be mixed with 95 mass-% of pulp of other material including poly-n-phenylene terephthlamide. Paper made from this pulp reduces rate of electric charge lesser than 150 ml.

EFFECT: enhanced efficiency.

6 cl, 4 tbl, 1 ex

FIELD: processes for manufacture of synthetic threads, fibers and filaments from polyamide.

SUBSTANCE: method involves mixing melts of two compounds, namely, linear polyamide and polyamide including macromolecular star-like or H-like chains comprising one or more nuclei, and at least three polyamide side chains or segments, which are bound with nucleus and produced from amino acid and/or lactam monomers, or multifunctional compounds with three similar acidic or amine functional groups; forming resultant melt mixture into threads, fibers or filaments and drawing if necessary.

EFFECT: increased effectiveness of process for producing of threads, fibers and filaments and improved elongation properties.

22 cl, 4 tbl, 6 ex

The invention relates to a technology for obtaining molded products - fibers or films based on aromatic copolyamid with heterocycles in the chain and can be used in the chemical industry for the reinforcement of plastics, rubber products, as tire cord, for obtaining fabrics and other materials for technical purposes and for the manufacture of films and pulp

The invention relates to the production of high-quality fiber pulp

The invention relates to the field of synthetic fibers, particularly synthetic fibers, spun from anisotropic solutions in sulfuric acid of rigid-rod aromatic polyamides, mixed with aliphatic polyamides

The invention relates to the field of production of high strength fibers based on aromatic depolimerization (ABI) used, usually in organoplastic aerospace, defense, etc

FIELD: processes for manufacture of synthetic threads, fibers and filaments from polyamide.

SUBSTANCE: method involves mixing melts of two compounds, namely, linear polyamide and polyamide including macromolecular star-like or H-like chains comprising one or more nuclei, and at least three polyamide side chains or segments, which are bound with nucleus and produced from amino acid and/or lactam monomers, or multifunctional compounds with three similar acidic or amine functional groups; forming resultant melt mixture into threads, fibers or filaments and drawing if necessary.

EFFECT: increased effectiveness of process for producing of threads, fibers and filaments and improved elongation properties.

22 cl, 4 tbl, 6 ex

Up!