Patent GB-1096048-A (GB)
Title: Improvements relating to the production of polymers
IPC: C08F2/50
Filed: 1965-04-30
Abstract: Photopolymerizable compositions comprise (A) at least one substance capable of undergoing cationic polymerization, (B) 0.001 to 5% of a fluorinated alkane sulphonic acid salt of formula RSO3M, where M is a silver (1) or thallium (1) cation and R is a perfluoro-alkyl group of up to 7 carbon atoms or a beta-hydroperfluoro-alkyl group of up to 7 carbon atoms and (C) a halide promoter in which the halogen is chlorine, bromine or iodine and which is dissociable by actinic light of wavelength between 2500<\>rA and 700 <\>rA.  Examples of fluorinated alkane-sulphonic acid salts are:  CF3SO3Ag, CF2HCF2SO3Tl, C2F5SO3Ag, (CF3)2CHCF2SO3Ag, n-C3F7SO3Ag, i-C3F7SO3Tl, n-C4H9SO3Tl, (CF3)2CF(CF2)4SO3Ag, n-C3F7CFHCF2SO3Ag, n-C4F9CFHCF2SO3Tl, n-C3F7CH(CF3)CF2SO3Ag, n-C8FnSO3Ag, n-C11F23SO3Tl, n-C5F11CFHCF2SO3Ag and n-C7F5CFHCF2SO3Tl. The halide promoters are either silver salts, e.g. the chloride, bromide and iodide or (preferably) organic halides such as chlorobenzene, o-dichlorobenzene, 2-5-dichlorothiopene, 3-iodofuran, 2-3-5-6-tetrachlorobenzequinone, 4 - 41 - dibromobiphenyl, polychlorinated terphenyls, the chloroxylenes, 7-bromoacenaphthene, 3 - 4 - dichloroethybenzene, alpha-paradibromoacetophenone and trichlorobenzene. While a solvent is not required and inert diluent or mutual solvent for the material to be polymerized and the initiator may be used; examples are hydrocarbons and ethers.  In the examples, the following catronic polymerizable substances are polymerization (1) 2-methoxy ethyl vinyl ether, (2), (3A), (3B) and (4) CH2=CHOCH2CH2OCH3, (5) CH2=CHO-i-C4H9. (6A), (6B) and (6C) CH2=CHO-t-C4H9, (7) and (10B) the tetravinyl ether of pentaerythritol, (8) 1,4-dimethyl-2-oxabicyclo-[2.1.1] hexan - 3 - one, (9) N - vinyl carbazole, (10) (a) diethylene glycol divinyl ether (c) 1,2,6-hexanetriol trivinyl ether, (d) 2-vinyl-4-(4-vinyl oxybutyl)-1-3-dioxolane, (e) tetraethylene glycol divinyl ether, (f) pentaerythritol divinyl ether, (g) 1-allyloxymethyl - 1,1 - di(vinyl oxymethyl)-propane, (h) isopropenyl butyl ether, (i) 2-vinyloxyethyl methacrylate, (j) 2-vinyl-oxyethyl methacrylate / methyl methacrylate ( 1/4 ), (k) 2-vinyloxyethyl methacrylate/butyl methacrylate ( 1/4 ), (l) vinyl ether of styrene/allyl alcohol ( 1/1 ), (m) glycidyl methacrylate/butyl methacrylate ( 1/10 ), (n) 1-4-cyclohexanedimethanol divinyl ether, (o) divinyl ether of 1,4-cyclohexanedimethanol/ethylene oxide (11) (p) 1-3-cyclobutanediol divinyl ether and (11) pentaerythritol tetravinyl ether/2-hydroxyethyl vinyl ether ( 1/1 ).ALSO:b  - Hydroperfluoroalkane - sulphonic acids are prepared by the addition of sodium bisulphite to perfluoro-olefins in the presence of a buffer such as borax.  Silver or thallium salts thereof are made therefrom by conventional methods.  Perfluoroalkane sulphonic acids are prepared from the corresponding perfluoroalkane sulphenyl chlorides which on oxidation with chlorine and water give the corresponding perfluoroalkane - sulphonyl chlorides; these hydrolysed to sulphonic acids and the acids neutralized give silver and thallium salts by conventional procedures.  1,4 - Dimethyl - 2 - oxa - bicyclo - [2,1,1] hexane-3-one is prepared by reacting 3-iodo-1,3 - dimethylcyclobutane - carboxylic acid with one equivalent of sodium hydride in ethyl ether at below 35 DEG  C. to give the sodium salt of 3-iodo-1,3-dimethylcyclobutane-carboxylic acid, followed by pyrolysis of the salt at 80-110 DEG  C. to give the desired lactone. The preparation of 3-iodo-1,3-dimethylcyclobutane-carboxylic acid is described in U.S. Specification 2,914,541.