Patent GB-955089-A (GB)
Title: Vinylthioalkyl esters of unsaturated carboxylic acids and polymers thereof
IPC: C08F291/00
Filed: 1960-07-11
Abstract: The invention comprises esters having the general formula CH2=CHSCnH2n (OCnH2n)m OCOCR=CHR DEG  in which R and R DEG  both represent hydrogen or one is hydrogen and the other is methyl, n is 2 or 3, each CnH2n group being such as to provide a chain of 2 or 3 carbon atoms between the hetero atoms to which it is joined and m is 0 or 1.  These esters may be prepared by reacting a C1-4 alkanol ester of a carboxylic acid of the formula HCR DEG =CR.COOH with an alcohol of the formula CH2=CHS Cn H2n (OCnH2n)mOH, R, R DEG , CnH2 and m being as defined above, the reaction being effected at an elevated temperature in the presence of an alkaline transesterification catalyst e.g., an alkali metal alcoholate, tetraisopropyl titanate or a quaternary ammonium alcoholate; preferably a polymerization inhibitor is present e.g., p-anilino phenol, N,N1-diphenyl-p-phenylene diamine, selenium dioxide, copper powder or cuprous chloride and a volatile solvent may also be present.  The esters may also be obtained from the vinyl thio alcohol and an appropriate acyl chloride.  The esters may be polymerised (see Division C3).  Examples describe the preparation of (1) the acrylic, methacrylic and crotonic acid esters of hydroxy-ethyl vinyl sulphide; (2) the methacrylic esters of 1-vinylthio-2-propanol and 2-(2-vinylthioethoxy) ethanol and (3) the methacrylic and crotonic esters of 1-(2-vinyl thioethoxy)-2-propanol.  The acrylic ester of (1) is obtained together with byproduct methyl b -(2-vinylthioethoxy) propionate and 2-vinylthioethyl b -(2-vinylthioethoxy) propionate. Other suitable vinyl thio alcoholic reactants are listed.ALSO:The invention comprises addition polymers comprising units having one of the formulae: <FORM:0955089/C3/1> <FORM:0955089/C3/2> <FORM:0955089/C3/3> in which R and R DEG  each represent hydrogen, with the proviso that one of R and R DEG  can represent methyl, m is 0 or 1 and n is 2 or 3, each CnH2n group being such as to provide a chain of 2 or 3 carbon atoms between the hetero atoms to which it is joined.  The invention also comprises a graft polymer of a polymer of one or more compounds containing a single CH2=C< and a monomer having the general formula: CH2=CHSCnH2n(OCnH2n)m OCOCR=CHR DEG  wherein R, R DEG , n and m have the above meanings.  The addition polymers may be prepared by polymerizing the said monomers alone or with other ethylenically unsaturated monomers using ionic or free-radical catalysts.  Cationic catalysts e.g., stannic chloride and BF3 and its complexes with oxygenated organic compounds polymerize the monomers via its vinyl group, while anionic catalysts e.g., alkali and alkaline earth metals, their amides and certain Lewis acid salts thereof effect the polymerization via the acid residue. Further polymerization may then be effected in each case via the other unsaturated group, by use of the other ionic catalyst, a free-radical catalyst, e.g. an organic peroxide or azo compound, or oxidation. Examples of the vinyl thio monomers include the acrylic, methacrylic and/or crotonic esters of hydroxy ethyl vinyl sulphide, 1-vinyl thio-2-propanol, 2-(2-vinylthio ethoxy) ethanol and 1-(2-vinyl thio ethoxy)-2-propanol. Monomers copolymerizable therewith are acrylates, methacrylates, vinyl esters, itaconates, acrylo- and methacrylonitriles, vinyl ethers, styrene, vinyl toluene, fumarates, maleates, vinyl triethoxy silane N-vinyl-2-pyrrolidone, methacryloxyethyl-2-pyrrolidone, N-vinyloxazolidinone and methacryloxy ethyl oxazolidinone. These polymerizations may be in bulk or in solution. Examples of homo and co-polymerization are given; in (23) 2-vinylthioethyl acrylate is copolymerized with ethyl acrylate using sodium amide as catalyst and the polymer obtained is dissolved in methyl methacrylate and further polymerized using an azo catalyst.  The vinyl thio monomers may be added to solutions of preformed polymers and graft polymerized thereto, examples being given of the graft polymerization of 2-vinyl thio ethyl methacrylate or (26) polymethyl methacrylate, (27) poly n-butyl methacrylate, (28) ethyl methacrylate/methyl acrylate copolymer, (29) a butyl/methyl methacrylate copolymer and (30) and (31) a methyl methacrylate/ethyl acrylate copolymer.