Abstract: A process for the polymerization of chloroprene or of a mixture of chloroprene and of up to 20% by weight of a copolymerizable monomer, in aqueous emulsion in the presence of radical initiators, at a temperature of between 5° C. and 70° C., characterized in that the polymerization is carried out in the presence of one or more copolymerizable surfactants in agreement with the formula described below (I)
R3—Z—CO—C(R1)═C(R2)—COOM (I)
where:
R3 is a saturated or unsaturated, linear or branched and aliphatic or aromatic Cn hydrocarbonaceous chain with n from 10 to 20;
R1 and R2, which are identical or different, are chosen from H or a C1-C3 alkyl radical;
Z is chosen from —O— and —NH—;
M is chosen from alkali metals or NH4.
Type:
Grant
Filed:
May 14, 2002
Date of Patent:
June 29, 2004
Assignees:
Enichem Elastomeres France S.A., Polimeri Europa S.p.A.
Inventors:
François Sauterey, Françoise Thenoz, Alain Guyot, Romano Lima, Piero Maestri, Francesco Masi
Abstract: The disclosure is made of a process for the polymerization of chloroprene or of a mixture of chloroprene and of up to 20% by weight of a copolymerizable monomer, in aqueous emulsion in the presence of radical initiators, at a temperature of between 5° C. and 70° C.
Type:
Application
Filed:
May 14, 2002
Publication date:
May 1, 2003
Applicant:
ENICHEM ELASTOMERES FRANCE S.A.
Inventors:
Francois Sauterey, Francoise Thenoz, Alain Guyot, Romano Lima, Piero Maestri, Francesco Masi
Abstract: The present invention relates to the preparation of (co)polychloroprene latex in water emulsion, in the presence of an emulsifying system which comprises a first step (A) wherein a fraction f.sub.1 of monomers is used together with an emulsifying system which comprises a non-carboxylic ionic emulsifying agent (Ea1), a non-ionic emulsifying agent with a low HLB (Eb1) and a non-ionic emulsifying agent with a high HLB (Eb2), and a second step (B) wherein the reaction medium of step (A) is fed with the remaining fraction f.sub.2 of (co)monomers and the remaining emulsifying system.
Abstract: A process for producing chloroprene by means of the dehydrochlorination of 3,4-dichloro-1-butene is disclosed, which is characterized in that the dehydrochlorination is carried out in the presence of lime and a primary amine having the general formula R--NH.sub.2, in which R is a monofunctional C.sub.1 -C.sub.15 hydrocarbyl radical selected from linear or branched alkyl, alkylaryl, cyclohexyl, alkylcyclohexyl, cyclopentyl, alkylcyclopentyl radicals.
Abstract: Process for preparing 1-chloro-1,3-butadiene, which consists in gas-phase dehydrochlorinating a dichlorobutene selected from 3,4-dichloro-1-butene and 1,4-dichloro-2-butene, in the presence of a catalyst selected from lanthanum phosphate and lanthanum phosphate doped with an alkali or alkaline-earth metal.