| 摘要 |
The known methods for modifying polymers by introducing sulfonate or sulfonic acid groups in the polymer chains have not resulted in products having satisfying characteristics. According to one known method a sulfonate monomer is used at the polymerization stage and according to another a polymer, e.g. polystyrene, is treated with a strong sulfonating agent e.g., sulfurtrioxide; this invention provides a two steps process for the preparation of polymers, which will contain an easily controllable amount of sulfonate groups. In the first step a copolymerization or a graft copolymerization is carried out using a controlled amount of an epoxy group containing monomer, the monomer being an ester of 2,3-epoxy propyl alcohol and acrylic acid. In the second step, the epoxy groups of the polymer prepared in the first step are, via a ring opening reaction, partially or fully sulfonated by means of sulfite ions in aqueous solution in the presence of a quarternary ammonium salt as catalyst; the polymers may be employed as thickening agents, surface coating materials. impregnating agents and binders, they may also be useful as antistatic agents ion exchange resins and catalysts. |
