SU1122674A1 - Process for producing synthetic latexes - Google Patents

Abstract

A method of producing synthetic JIATEKCOB by water-emulsion copolymerization of butadiene with styrene or acrylonitrile in the presence of an emulsifier of the initiating system, a molecular weight regulator, in order to increase the strength properties of vulcanizates based on the target product, . h, at 100 ma.h. the comonomers of the polycarboxylic acid of the general formula CH3, COOCHHCH2MO (K2) with where Br is CHH-C J —CH3 — CH-; CN j SKSffi% VYPV9-CH2-C-V b2-CH5; -CgHs; i СООСНз tt t 190-385

Description

1 I

The invention relates to a method for producing synthetic latexes based on butadiene and can be used in the petrochemical industry to obtain nonwoven materials by the method of impregnation with liquid binders.

A known method for producing synthetic latexes by aqueous emulsion copolymerization of butadiene with vinyl monomers in the presence of a polymeric emulsifier. A copolymer of decyl acrylate with acrylic acid with a molecular weight of not less than 10,000 is used as a polymeric emulsifier. The process is carried out in the presence of a radical initiator (potassium persulfate), a molecular weight regulator 1 J.

However, the latexes obtained by this method have low resistance to the introduction of electrolytes, low water resistance and strength of plume from them.

It is known to obtain a polymer emulsion by water-emulsion copolymerization of conjugated dienes, incl. and butadiene, with styrene or acr. pyunitrile and diethylaminoeth1-shacrylate (0, 1-8.0%). The resulting emulsions have a surface activity of U2 3- However, the use of such emulsion, copolymers in impregnating compositions does not allow to obtain

SNS.-C -} -,

COOCHgCH2l O (R2} g.

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vulcanizates with sufficiently high strength properties.

The closest to the technical essence of the invention is a method of producing synthetic latexes by water-emulsion copolymerisation of butadiene with styrene or acryloniiryl in the presence of emulsifiers, the initiator system, and the molecular weight regulator.

Polyoxyethylated fatty or aromatic compounds with a degree of polyoxyethylation of less than 40% are used as an emulsifier. Known synthetic latexes are resistant to mechanical effects, to the introduction of electrolytes, active fillers and 31

However, the known latexes allow obtaining vulcanizates with sufficiently high strength properties in impregnating compositions.

The aim of the invention is to increase the strength properties of vulcanizates based on the target product.

The goal is achieved by the fact that according to the method of producing synthetic latexes by water-emulsion copolymerization of butadiene with 30 styrene or acrylonitrile in the presence of emulsifiers of the initiating system, molecular weight regulator, I-IO mac. on 100 ma.ch. somo35 numbers semi amine oxide of general formula

rAeRi: -CH2- j H-;

Sbne

R2 - CH3, --C2H55

"Ifl 190 - 385 Conduct water-emulsion copolymerization of butadiene with styrene or acrylonitrile at 30 - 50 ° C in the presence of a radical activator of the activator, molecular weight regulator and the specified el Yelgator, introduced into the aqueous phase before loading the monomers .; As polyamine oxide of the specified formula is used

CHg-CH-; -CHg-G-;

CN СООСНз dialkylaminoethyl methacrylate copolymer seed with styrene, or acrylonitrile, or methyl methacrylate; as the initiating system - persulfate, potassium in combination with triethanolamine; the molecular weight regulator is tertiary dodecyl mercaptan. Co-polymerization is carried out to a conversion depth of about 100%, at the end of 3 a solution of hydroquinone is introduced and the non-polymerized monomers are distilled off under vacuum. The polymeric polyamine oxides used are obtained by copolymerization of dialkylaminoethyl methacrylate with styrene or acrylonitrile or methyl methacrylate, taken in equimolar ratio, in an aqueous medium in the presence of a radical initiator — potassium sulphate — at 70– 90 s. within 2-3 hours to 100% conversion of monomers, and the polymer obtained is treated with an amount of hydrogen peroxide, equimu- lar with dialkylaminoethyl methacrylate, at 50 for 0.5–1.0 h, dried out from an aqueous solution with acetone and dried with 60 - to constant mass. Example 1. Butadiene is copolymerized with acrylonitrile in a 40:60 weight ratio in the presence of 10 parts by weight of a dimethylaminoethylmethacrylate N-oxide copolymer. with styrene with p m 310, 0.3 wt.h. potassium persulfate, 0.15 wt.h. triethanolamine, 0.3 wt.h. tertiary dodecyl mercaptan and 150. mash. water at 30 ° C. The copolymerization time is 16 hours; at the end enter 0.2 wt.h. hydroquinone in solution and the non-polymerized monomers are distilled off under vacuum at 80 ° C. Example 2 A copolymerization of butadiene with acrylonitrile was carried out in a mass ratio of 76:24 in the presence of 5 parts by weight. N-oxide of a copolymer of diethylaminoethyl methacrylate with methyl methacrylate with p m 385, 0.3 wt.h. potassium persulfate, O, 15 wt.h. triethanolamine, 0.3 May. tertiary dodecyl mercaptan and 150 wt.h. water at. The copolymerization time is 17 hours; in the course of processing, the latex is treated as in Example 1. J,, PRI me R 3. The copolymerization of butadiene with styrene is carried out in a mass ratio of 70:30 in the presence of I wt.h. N-oxide of a copolymer of dimethylaminoethyl methacrylate with acrylonitrile p w 190, 0.3 wt.h. potassium persulfate 0.15 wt.h. tri-ethanolamine, 0.3 wt.h. tertiary dodechschlmercaptan and 150 parts by weight of water at 30 ° C. The copolymerization ratio of the copolymerization agent was 44 h 18 h; after the end, the latex was treated as described in Example 1. EXAMPLE 4 The butadiene and styrene were copolymerized in a weight ratio of 70:30 in the presence of 3 wt.h. N-oxide of a copolymer of diethylaminoethyl ketacrylate with acrylonitrile with p m 260, 0.3 wt.h. potassium persulfate, 0.15 wt.h. triethanolamine, 0.3 wt.h. tertiary dodecyl mercaptan and 150 wt.h. water at 50 ° C. The copolymerization time is 10 hours; at the end of letex, process according to the example of p and mep 5. (control method l). The copolymerization of butadiene with acrylonitrile, taken in a mass ratio of 76:24 in the presence of 5 wt.h. a water-soluble copolymer of decylacrylate with acrylic acid with a molecular weight of 80,000, 0.3 wt.h. potassium persulfate, 0.15 wt.h. triethanolamine, 0.3 wt.h. tertiary dodecyl mercaptan and 150 wt.h. water at. The copolymerization time is I 16 hours; at the end, the latex is treated as in example I. Example 6 (control according to the prototype). Butadiene is copolymerized with acrylonitrile, taken in a weight ratio of 56: 44, in the presence of 8% by weight as an emulsifier. ethoxylated higher fatty alcohols (OS - 20), persulfate, potassium, 0.15 wt.h. triethanolamine at 100% before the conversion of monomers, at the end of the latex is treated according to example 1. Table 1 shows data on the testing of the obtained samples of latexes. The following parameters were determined: dry residue, pH, surface tension, measured by a Du-Nuy tensiometer, resistance to the introduction of electrolytes, as determined by the standard method, with calcium chloride concentration from. 1 to 14 mmol / l, as well as the water resistance of films. As can be seen from the above data, the proposed method of producing synthetic latexes using polyamoxide as a polymeric emulsifier allows one to obtain latexes possessing resistance to the introduction of electrolytes, active

S11226746

performers. Polymer amine oxide films, which are not washed out of such, are water-resistant, kimi films. In tab. 2 shows the zico-mechanical properties of vulcanizates. As can be seen from the table, the basis of the impregnating composition, the content of the proposed latexes

. zhaschey 100 ma.ch. latex, in the calculation allows to obtain vulcanizates with a dry matter, 15 wt.h. metasi-strength indicators,

on ammonium chloride and I.h. ammonium chloride. What is necessary to obtain a quality of Vulcanization is carried out by 15 mineral nonwovens on the base of 10 latexes. Properties

shpgp

The dry residue% 37.4 39.2 38.3 40.2 40.1 42.1

latex pH 5,2 5,5 5,9 6,0 5,9

Surface

tension, mn / m 38.5 38.5 40.0 39.5 38.5 45.2

, , .; ....

Resistance to Stability within the entire scale Coagu-Resistant in Ca ion; , liet limits.

Water resistance I films% water absorption. in 24 hours

3.1 3.23.5 3.7

Table 1

Example

whole scale

20

П226748

Indicators

EIELEriZIZlE:: Stress at elongation-. SRI 300%, kgf / Y 51 47 53 Strength at break, kgf / cm. 60 185 190 Relative elongation,% 550 600 500 Residual elongation,% 16 14 12

 Control method El3. Prototype checklist. Controle by method 12.

table 2

Examples 57 15 11 25 205 75 50 70 450 700 830 650 P 25 31 21

Claims (1)

METHOD FOR PRODUCING SYNTHETIC LATEX by water-emulsion copolymerization of butadiene with styrene or acrylonitrile in the presence of an emulsifier of an initiating system, molecular weight regulator, characterized in that, in order to increase the strength properties of vulcanizates based on the target product, 1-10 wt. , for 100 ma.ch. comonomers of a polyamine oxide of the general formula cn ₅ • £ ^R 4m [ ^CH2 “-? 4n. coax ₂ sn ₂ ^ o (in ₂ ) ₂ , B ^ -CHg-CH ·; - CH ₂ —CH—; Sat ₅ CN Sn I ³ -sn ₂ -s ~; n ₂ = -chs; - ^c 2 ^H s; СООСНз ft = t = 190 - 385 Iya * yu O) m I 122674