| 摘要 |
chemistry of polymers. SUBSTANCE: described is method of preparing (co)polychloroprene latexes by homopolymerization of chloroprene in aqueous emulsion or copolymerization of mixtures of chloroprene and up to 50 wt. % of copolymerizable monomers in the presence of at least one radical initiator and emulsifying system consisting of (a) at least one ionic non-carboxylate surfactant (Eal) and (b) at least two nonionic surfactants (Eb1) and (Eb2) which differ from each other in hydrophillipophile balance by three unites or more. Method comprises first stage (A) for preparation of aqueous emulsion comprising composition f1 composed of (co)monomers and polymers with polymer content between 0 and less than 100 wt.% calculated for dry matter with respect to composition, emulsifying system which includes ionic noncarboxylate emulsifier (Ea1) in amount ranging from 10 to 50 wt. % based on total amount of emulsifier used in the process, nonionic emulsifier (Ea1) having lower value of hydrophilic lipophilic balance in amount ranging from 2 to 90% based on total amount of emulsifier (Eb1) used in the process, nonionic emulsifier (Eb1) having higher value of hydrophilic-lipophilic balance in amount ranging from 0 to 25% based on total amount of emulsifier (Eb2) used in the process, degree of conversion being at least 1%, second stage (B) in which the remaining composition f2 (f1+f2-100 wt parts) of comonomers with the remaining emulsifying system is added to aqueous composition prepared in stage (A) for promotion of polymerization. Also described adhesive, additive and (co)polychloroprene latex. Also described is method of copolymerization of chloroprene which makes it possible to prepare latexes having storage stability, resistance to polyvalent metals, high chemical properties and improved adhesive properties. EFFECT: greater efficiency and safer process. 18 cl, 13 ex, 3 tbl
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