Hydrolysis/-butyl methacrylate-containing block copolymers

By employing anionic techniques, alkyl methacrylate containing block copolymer systems have been synthesized with controlled compositions, predictable molecular weights and narrow molecular weight distributions. Subsequent hydrolysis of the ester functionality to the metal carboxylate or carboxylic acid can be achieved either by potassium superoxide or the acid catalyzed hydrolysis of t-butyl methacrylate blocks. The presence of acid and ion groups has a profound effect on the solution and bulk mechanical behavior of the derived systems. The synthesis and characterization of various substituted styrene and all-acrylic block copolymer precursors with alkyl methacrylates will be discussed. 

Teyssie and coworkers found that the anionic polymerization ( Living Polymer-formation ) of methacrylate and acrylate esters in the presence of lithium chloride along with the anionic initiator results in polymers with particularly uniform molecular weight distributions. By this technique, di-and tri-block copolymers and star-block copolymers may readily be prepared. If rerr-butyl acrylate (or methacrylate) is one of the comonomers, hydrolysis of such copolymers with a small amount of / -toluenesulfonic acid leads to a copolymer containing acrylic (or methacrylic) acid [25-27]. 

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