초록 ▼

Improved water-absorbing, crosslinked acrylate resins are prepared by aqueous polymerization of (A) acrylic acid neutralized 70 to 100 mole percent for example with ammonia and/or caustic alkali and/or an amine; with (B) acrylamide in a mole ratio of 70 to 100 mole percent (A) to 30:0 mole percent (

Improved water-absorbing, crosslinked acrylate resins are prepared by aqueous polymerization of (A) acrylic acid neutralized 70 to 100 mole percent for example with ammonia and/or caustic alkali and/or an amine; with (B) acrylamide in a mole ratio of 70 to 100 mole percent (A) to 30:0 mole percent (B); and (C) a water miscible or a water soluble polyvinyl monomer in the presence of (D) a styrene-maleic anhydride copolymer, neutralized 70 to 100 mole percent for example with ammonia, and/or caustic alkali and/or an amine, in an amount of 1% to 25% based on the weight of acrylic acid or acrylate, such that the amount of (C) is 0.001 to 0.6 weight percent based on the total weight of (A), (B), (C) and (D). In addition, surface treating the water-absorbing crosslinked acrylate resins with a polyquaternary amine substantially further increases both the rate of water absorption and the quantity of water absorbed and retained by the resin. The untreated and the surface-treated resins also maintain the necessary “dry feel”required for most applications.

대표청구항 ▼

A process for preparing a solid water absorbing resin of improved water absorbency comprising mixing a solution of (A) acrylic acid neutralized 70-100 mole percent; (B) a water-soluble styrene-maleic anhydride resin in an amount of about 1% to about 25% based on the weight of acrylic acid and neutra

A process for preparing a solid water absorbing resin of improved water absorbency comprising mixing a solution of (A) acrylic acid neutralized 70-100 mole percent; (B) a water-soluble styrene-maleic anhydride resin in an amount of about 1% to about 25% based on the weight of acrylic acid and neutralized 70-100 mole percent; and (C) a water-miscible to watersoluble polyvinyl monomer in a combined concentration of (A), (B) and (C) of at least 30 wt. %; with water to form a mixed solution and initiating polymerization of monomers (A) and (C) such that during polymerization, the exothermic heat of reaction is substantially the only heat energy used to accomplish polymerization, crosslinking and to drive off sufficient water to obtain a solid crosslinked resin including resin (B) and having a water content of 15 percent by weight or less.