Preparation of gel

Abstract

Abstract PURPOSE:To improve crosslinking efficiency, heat resistance, mechanical strengths, and water content by keeping a soln. of a specific polymer at a low temp. and irradiating the soln. with rays of light. CONSTITUTION:A saponified copolymer of vinyl ester with a hydrophilic monomer is made to react with a compd. of formula I [wherein A is a formly or acetal group; R<1> is H, lower alkyl, or lower alkoxy; R<2> is a residue of (a salt of) a heterocyclic compd. or an aryl group; (m) is 1-6; and (n) and (p) are each 0 or 1] to give a polymer having a wt.-average mol.wt. (in terms of polyethylene glycol) of 5000-50000 and structural unit of formula II. 1-50wt.% said polymer is dissolved in a solvent capable of dissolving a PVA deriv. and the resulting soln. is kept at 0 deg.C or lower until it freezes and irradiated with rays of light having a wavelength necessary to cause photodimerization, i.e., 600nm or lower, at an intensity of 1-100mW/cm<2> at 10-25 deg.C for 1-60min.

Inventors

• 👤 Yasushi Tamada
• 👤 靖 玉田
• 👤 Kenji Yasuda
• 👤 健二 安田

Bibliographic Details