The present invention relates to block polymers comprising methacrylic acid and derivatives of methacrylic acid as well as a method for the preparation of such block polymers. In the past, carboxylic acid containing polymers have been typically synthesized by the direct free radical polymerization of various carboxylic acids, as well as ester, or anhydride derivatives thereof with various vinyl comonomers. The corresponding carboxylic salt derivatives or ionomers are typically prepared by partial or complete neutralization of carboxylic acid groups with various basic compounds. Previously known synthetic routes have resulted in the random placement of such acid or ionic groups along polymer backbones. It would be desirable to provide similar polymeric structures having controlled composition and architecture, predictable molecular weights and narrow molecular weight distributions.
In pending application Ser. No 70,269, filed July 6, 1987, two of the present coinventors and one other disclosed and claimed block copolymers of a diene and methacrylic acid and derivatives of such block copolymers.
It is previously known to use anionic polymerization techniques for the preparation of block polymers having controlled morphology and composition as well as architecture and predictable molecular weights, as well as narrow molecular weight distributions.
Moreover, it is previously known that tertiary butyl methacrylate may be polymerized by anionic techniques. All methacrylate block copolymers of methyl methacrylate/ethyl methacrylate, methyl methacrylate/n-butyl methacrylate and methyl methacrylate/t-butyl methacrylate were disclosed in Polymer Preprints 26(1) 1985, pg. 247-248.
USPTO Backgrounds
USPTO Backgrounds