(2-n,n-diethylaminoethyl)-4- hydroxy -3,5di-tert - butylbenzaldehyde as coagulant emulsion rubbers

 

(57) Abstract:

The invention relates to substituted bansilalpet, in particular (2-N,N-diethylaminoethyl)-4-hydroxy-3,5 - di-tert-butylbenzaldehyde with coagulating activity that can be used in the manufacture of synthetic emulsion rubbers. Goal - the creation of new more effective substances of the specified class. Synthesis of lead processing Mannich bases of 2-diethylaminoethylamine at 120 - 130°C and 2 mm RT.article by distillation of the excess amine. Yield 98%; mol.m. 346. A new substance used in the process of coagulation of latex rubber SKS-30 AMIS at 60%, followed by acidification with an aqueous solution of sulfuric acid. Consumption of coagulant is reduced from 3.7 to 2.9 kg/so 1 Il., 5 table.

The invention relates to the production of synthetic rubber by emulsion polymerization method.

It is known that at the present time in the manufacture of IC at the stage of selection of rubber from latex spent 200-250 kg of salt or 30-90 kg aluminum salts or calcium per 1 ton of rubber. The use of large quantities of salts in the allocation of rubber from latex causes salinization of the most valuable freshwater reservoirs, which leads to irreversible changes in their communities and n is atiti or exclude salinization of freshwater reservoirs.

However, firstly, metacid has a high bactericidal and fungicidal action, so its accumulation in serum and lavage leads to disruption of biological wastewater treatment.

Secondly, the coagulation of rubber with metacid is different from the industrial technology selection rubbers using known coagulants - proteins, NaCl and the proposed new coagulant Navy-80.

Known protein coagulant Navy-100A.

When using protein coagulants in industry the UK has found the following disadvantages:

protein hydrolysates in the hot season and warm regions of the country are exposed to bacterial contamination and subsequently rot, forming products of metabolism with an unpleasant odor;

to avoid contamination of the equipment upon receipt, storage, transportation and use of protein hydrolysates required thorough rinsing with water, long-term treatment with live steam and process disinfecting solution of formalin;

protein hydrolysates are not independent stabilizers rubbers, they are applied only in the presence of additional stabilizers, providing pological at the same time the ability of effective coagulant and stabilizer for rubbers.

This goal is achieved using (2-N,N-diethylaminoethyl)-41OK-si-31, 51di-tert-butylbenzaldehyde formula (I) as a coagulant rubber

(I)

The compound of formula (I) are not described in literature. It has the following advantages;

has a simple way to obtain;

at the same time is an effective coagulant and anti-roll rubber;

the offered product is not subject to bacterial contamination and does not require preservatives;

the offered product can be used both independently and in a mixture with known coagulants from a number of proteins, synthetic amines.

The invention is illustrated by the following examples.

P R I m e R 1. In a three-neck flask equipped with a reflux condenser and a thermometer, loads of 52.6 g (0.2 mol) of Mannich bases (TU 38.103368-87) and 29.2 g (0.22 mol) of 2-Diethylaminoethanol [Catalog Handbook of Fine Chemicals, Aldrich Chemical Company. 1986-1987 G., R. 465; Sigma Price List, 1987, 508].

The reaction mixture is heated to a temperature of 120-130aboutC for 5 h and then distilled off the excess 2-diethylaminoethylamine at 2 mm RT.article In the flask remains the finished product, representing masljanistej)-41-hydroxy-31, 51di-tert-butylbenzaldehyde) is a transparent oily liquid with a refractive index (nD20), equal GBPUSD crossed over 1.5100.

Found, %: C 72,1; H 10,4; N 4,1; S 8,8.

Mol. weight 346.

Calculated, %: From 71.8; H 10,5; N 4,0; S 9,1.

Mol. mass 351.

PMR-spectrum, shown in the drawing is cleared spectrometer

EM-390 "Vrian"; working frequency of 90 MHz.

The internal standard tetramethylsilane was (T. M. S.).

Further to simplify the connection - 2-N,N-diethylaminoethyl-41-hydroxy-31, 51di-tert-butylbenzaldehyde, will be presented under the cipher Navy-80.

P R I m m e R 2. In 100 ml best choice (-methylstyrene) latex, pre-heated to 60aboutWith, with stirring, first enter the coagulant Navy-80, and then serves a 1% aqueous solution of H2SO4to pH 3. After 10 minutes of mixing is complete coagulation of the latex serum transparent.

In control experiments using known protein coagulant Navy-100A and known metacid. Coagulation is carried out in the same conditions.

The selected rubber is washed, dried and subjected to tests under heat aging at 140about

COI = 100%.

The results in the consumption of coagulants and their ability to stabilize the rubber under heat aging are given in table. 1.

Results table. 1 confirm that the product Navy-80 is simultaneously effective coagulant and anti-roll rubber.

P R I m e R 3. 100 ml of the production the best choice latex rubber SKS-ARK and SCS-ARKM-15 enters a different dosage of the product offered Navy-80 and docomplete carried out by adding the required amount of protein coagulant Navy-100A acidification with 1% solution of N2SO4to rn.

The obtained rubber was washed, dried and subjected to the tests for resistance to heat aging (COI) and determine the content of gel in the polymer.

In table. 2 shows the results of the tests.

In table. 2 shows that the proposed product causes a significant reduction in coagulant Navy-100A, and the dosage of the Navy-80 3 kg/ton of rubber does not require additional protein coagulant. The resistance of rubbers to heat ageing in a joint application products Navy-100A and Navy-80 is at a high level.

P R I m e R 4. In 100 ml best choice latex cout Navy-80. The latex is heated to 60aboutWith and allocate additional introduction of coagulant Navy-100A acidification 1% N2SO4or without coagulant Navy-100A only using 1% aqueous solution of sulfuric acid.

Control experiments are performed with the product of the Navy-100A and 1% N2SO4.

The results of the expenditure of the coagulants are given in table. 3.

In table. 3 shows that with the decrease of the dispersant lakanal in latex significantly reducing the amount of coagulant Navy-80 allocation rubber as when it is used alone, or in combination with coagulant Navy-100A.

P R I m e R 5. In 100 ml on BNR and polybutadiene latex synthesized in the presence of emulsifier potassium soap of FLC (fraction10-C16and disperser of lakanal, first enter the desired amount of product Navy-80 and 1% N2SO4to pH 3. Rubber has been fully allocated, serum transparent. Control experiments carried out with the coagulant Navy-100A and metaldom.

Ready rubbers are tested for stability against heat aging (COI).

The results in the consumption of coagulants and COI are shown in table. 4.

P R I m e R 6. In pre-heated to 60aboutWith latex when pechanga selection of rubber.

These conditions are optimal allocation only for coagulant metacid.

In table. 5 shows comparative data on the consumption of coagulants - metacid and Navy-80.

The presented results confirm that the expenditure proposed coagulant Navy-80, unlike metacid not depends on how and where to enter it in latex.

(2-N,N-DIETHYLAMINOETHYL)-4'-HYDROXY-3',5'-DI-TERT-BUTYLBENZALDEHYDE AS COAGULANT EMULSION RUBBERS.

(2-N, N-diethylaminoethyl)-4'-hydroxy-3', 5'-di-tert-butylbenzaldehyde formula

< / BR>
as coagulant emulsion rubbers.

 

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2 tbl, 18 ex

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1 dwg, 7 tbl, 7 ex

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3 tbl, 7 ex

FIELD: chemistry.

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25 cl, 15 tbl, 38 ex

FIELD: chemistry.

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EFFECT: nitrile rubber characterised by high stability during storage and high rate of vulcanisation are obtained, as well as with a preferable profile of properties, mainly with respect to contact of moulded articles based on such vulcanised rubber with metal structural components.

25 cl, 15 tbl, 5 dwg, 5 ex

Nitrile rubber // 2479591

FIELD: chemistry.

SUBSTANCE: nitrile rubber contains repeating units of at least one α,β-unsaturated nitrile and at least one conjugated diene and has ionic index in the range of 7-26 ppm×mol/g. The nitrile rubber is obtained by emulsion polymerisation. The obtained latex, which contains nitrile rubber, is coagulated and the coagulated nitrile rubber is washed. Polymerisation is carried out in the presence of at least one alkylthiol. Before coagulation, the pH of the latex is set to at least 6, and coagulation is then carried out in the presence of at least one salt of a monovalent metal. The latex coagulation temperature ranges from 60 to 90°C and the washing temperature ranges from 50 to 90°C. The obtained nitrile rubber is used to obtain curable mixtures which contain said rubber and at least one cross-linking agent. The curable mixtures are cured by moulding to obtain moulded articles.

EFFECT: nitrile rubber has excellent curing rate and exceptional properties of cured products.

26 cl, 7 tbl, 13 ex

FIELD: chemistry.

SUBSTANCE: method of separating emulsion polymerisation rubber involves coagulation of rubber latex in an acidic medium in the presence of a coagulant - polydiallyl dimethylammonium chloride. An aqueous solution of the coagulant with concentration of 4.3-4.8% is premixed with serum in a flow mixer in ratio of coagulant to serum of (0.115-0.150):(30-45) m3/h and then fed into a coagulation apparatus from the bottom simultaneously with sulphuric acid solution. Latex is fed into the coagulation apparatus from the top in ratio of latex to serum of 1:(2.4-2.7). Coagulation is carried out in an acidic medium at pH 5.4-6.3 and temperature 50-60°C. After coagulation, rubber crumbs flow under gravity into a maturing tank, for pressing, drying and briquetting.

EFFECT: invention simplifies the method and improves the quality of the obtained rubber.

3 cl, 1 dwg, 1 tbl, 6 ex

FIELD: polymer materials.

SUBSTANCE: invention is dealing, in particular, with thermally processed tetrafluoroethylene copolymers having predominantly spherical shape for at least 95 wt % of material. Median microsphere size lies within a range of 25 μm to 2 mm and bulk density between 0.5 and 1.1 g/cm3. Invention also concerns coagulation apparatus and microsphere preparation process.

EFFECT: enabled preparation microspheres of thermally processed tetrafluoroethylene copolymer characterized by specified morphology, controlled size, and improved fluidity.

18 cl, 2 tbl, 14 ex

FIELD: polymers, chemical technology.

SUBSTANCE: invention relates to the continuous method for preparing polytetrafluoroethylene (PTFE) or modified PTFE finely divided powders. The continuous method for preparing PTFE or modified PTFE finely divided powders involves the following steps: (a1) dilution of PTFE-latex of modified PTFE-latex prepared in polymerization in the dispersion-emulsion to the concentration from 5 to 25 wt.-% of PTFE or modified PTFE with possible filtration of the prepared diluted latex; (b1) molding latex with inert gas to the relative pressure with respect to atmosphere pressure in the range 3-40 kg/cm2 (0.3-4 MPa); (c1) addition of acid electrolyte solution to latex in the line-flow mixer at pH value 1-4; (d1) feeding the latex flow from the mixer through capillary tube under condition of turbulent current with the Reynolds number above 3000; (e1) gel prepared at step (d1) is coagulated onto granules at mechanical stirring with the specific power 1.5-10 kWt/m3 and stirring is maintained up to flotation of finely divided powder; (f1) below water is separated from the finely divided powder. PTFE of modified PTFE finely divided powders that can't be processed by thermal method prepared by abovementioned method show the following indices: apparent density is ≥ 470 g/l; average diameter of particles (D50) is above 200 mcm; distribution of particles by diameter determined as ratio between particles mass with diameter from 0.7 to 1.3 times with respect to average particles diameter and the total particles mass above 50%. Invention provides preparing powders without using the complex and expensive equipment, and powders possess the improved fluidity and show the apparent density and narrow distribution of particles by the diameter index.

EFFECT: improved preparing method.

9 cl, 1 tbl, 1 dwg, 6 ex

FIELD: chemistry.

SUBSTANCE: present invention refers to emulsion rubber recovery from latex and can be used in chemical rubber industry. There is disclosed method of emulsion rubber recovery from latex through coagulation with using bivalent metal salts from magnesium chloride, magnesium sulphate, calcium chloride. Thereafter rubber crumb is separated from serum, it is followed with wringing and drying, differing that mixing latex and bivalent metal salt is preceded with pre-acidification of latex with diluted sulphuric acid concentrated 0.3-4% to pH 2.5-7.0 units. Within mixing range of acidulous latex and bivalent metal salt, concentration of the latter is kept within 0.05-0.8%, while produced rubber crumb is wrung out thus maintaining pH of wringing water within 2.5-6.9 units with sulphuric acid supplied to pre-acidification of latex.

EFFECT: making uniform rubber compatible with the requirements of related GOST and rubber TOR specifications in characteristics - mass fraction of organic acid soaps and mass fraction of organic acids, improved technological effectiveness and ecological compatibility of process.

2 cl, 1 tbl, 14 ex

FIELD: chemistry.

SUBSTANCE: rubber is extracted from latex continuously by mixing latex with a coagulant. Consumption of coagulant is varied depending on the given turbidity value of serum (primary serum), which is maintained by the amount of coagulant fed. The given turbidity value of primary serum is adjusted depending on the turbidity of the serum released (secondary serum) towards the minimum consumption of coagulant to obtain minimum turbidity of the released serum.

EFFECT: method of controlling the coagulation process enables to reduce contamination of waste water through loss of partially coagulated latex with minimum consumption of coagulants.

2 dwg, 6 ex

FIELD: chemistry.

SUBSTANCE: method of extracting butadiene-nitrile rubber from latex is carried out by feeding sodium sulphite or sodium bisulphite or sodium pyrosulphite in amount of 0.05-0.8 wt % per latex, into a stream of latex degassed beforehand, into which an antioxidant emulsion is also fed. Further, the stream of latex, containing sulphite, is directed into a coagulation apparatus into which aqueous sulphuric acid and an organic amine coagulant in form of a quaternary polymer ammonium salt are also simultaneously fed, said salt being selected from: polydimethyl diallyl ammonium chloride, a methacrylamide and dimethyl aminoethyl methacrylate hydrochloride copolymer, and polydiethyl aminoethyl methacrylate hydrochloride. The amount of the polymer ammonium salt varies from 0.2-0.5 wt %, per rubber, depending on content of leukanol content in latex in the range of 0.1-0.4 wt %, per rubber, at coagulation pH 3-6 and temperature 30-70°C.

EFFECT: invention improves environmental friendliness of the process, specifically reduces content of unreacted monomer - free acrylic acid nitrile, avoids excess synthetic coagulant and the amount of salt used for coagulation.

3 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: described is nitrile rubber which contains repeating units of at least one α,β-unsaturated nitrile and at least one conjugated diene, and also contains magnesium ions in concentration of 100-180 ppm and calcium ions in concentration of 50-145 ppm, respectively, with respect to nitrile rubber. Described is a method of producing said nitrile rubber via emulsion polymerisation of at least one α,β-unsaturated nitrile, at least one conjugated diene and optionally one or more other copolymerisable monomers selected from a group comprising α,β-unsaturated mono- or dicarboxylic acids, esters and amides thereof, in the presence of at least one molecular weight regulator, with the latex which is obtained during polymerisation and contains nitrile rubber being subjected to coagulation and the coagulated nitrile rubber subsequently being washed, wherein (i) the latex obtained during emulsion polymerisation has a pH of at least 6 before the coagulation, (ii) coagulation of the latex is carried out using at least one magnesium salt, up to 40 wt % of which is optionally replaced with a calcium salt, as precipitant, (iii) the coprecipitant used during coagulation of latex is gelatine, (iv) temperature of latex before reacting with the coprecipitant (iii) is kept higher than 50°C, and then raised to 100°C, and (v) coagulation of latex and/or treatment of the coagulated latex is carried out using water containing calcium ions, under the condition that coagulation is carried out without a calcium salt as a precipitant. Treatment of nitrile rubber obtained using the method described above is described, wherein nitrile rubber is subjected to (i) either a metathesis reaction only or (ii) a metathesis reaction and subsequent hydrogenation, or (iii) hydrogenation only, to obtain optionally hydrogenated nitrile rubber. Described is use of said nitrile rubber, optionally hydrogenated nitrile rubber, to obtain vulcanised mixtures, obtained by mixing at least one nitrile rubber or at least one optionally hydrogenated nitrile rubber, at least one cross-linking agent and optionally other additives. Described is a method of making moulded articles, such as a seal, a cap, a hose or a diaphragm, in particular an O-ring seal, a flat seal, a dynamic seal, a sealing sleeve, a sealing cap, a cap for protection from dust, a plug seal, a thermal insulation hose (with or without a PVC additive), an oil cooler hose, an air hose, a servo control hose or a pump diaphragm, through vulcanisation during moulding, via pressure casting of said vulcanised mixture.

EFFECT: special nitrile rubber, characterised by high stability during storage and high rate of vulcanisation is obtained.

25 cl, 15 tbl, 38 ex

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