EXAMPLES OF NEW SYNTHETIC ROUTES TO PENDANT ESTER ETHER DERIVATIVES OF ALPHA-HYDROXYMETHYLACRYLATE POLYMERS

Three routes to new ester-ether derivatives of ethyl alpha-hydroxymeth ylacrylate (EHMA) and t-butyl alpha-hydroxymethylacrylate (TBHMA) were investigated. The first approach involved the preparation of chloroac etate derivatives of EHMA and TBHMA as intermediates followed by attem pted etherification of the chloroacetate group. All attempted nucleoph ilic reactions of ethyl alpha-chloroacetoxymethacrylate (ECAM) and t-b utyl alpha-chloroacetoxymethacrylate (TBCAM) gave Michael-type substit ution products with loss of the a-chloroacetyl substituent. polymer su bstitution was therefore investigated. Bulk polymerization of ECAM wit h AIBN gave unexpectedly high molecular weight polymer with a number a verage value of 1.15 million, This homopolymer was substituted with 4- phenylphenol in excellent conversion. The second approach involved the reaction of ethyl alpha-chloromethylacrylate (ECMA) with alpha-ethers of acetic acid sodium salts using phase transfer catalysis. The metho xyacetate derivative was prepared and polymerized to give a polymer wi th a number average molecular weight of 260,000. The third route to es te-ether derivatives involved three steps: reaction of t-butylchloroac etate with an alcohol to give the ether, conversion of the t-butyl gro up to the acid chloride, and reaction of the acid chloride with EHMA o r TBHMA. The 2-(4-phenylphenoxy)acetate derivative of EHMA was prepare d using this method, and converted to high polymer.