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); (C) styrene, in an amount of 0% to 25% based on the weight of acrylic acid or acrylate; and (D) a water miscible or a water soluble polyvinyl monomer in the presence of (E) a metal oxide, such as titanium dioxide, in an amount of 0.001% to 5% based on the total weight of (A), (B), (C), (D) and (E), such that the amount of (D) is 0.001 to 0.6 weight percent based on the total weight of (A), (B), (C), (D) and (E). 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 metal oxide-containing 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 comprising mixing a solution of (A) acrylic acid neutralized 70-100 mole percent; (B) a non-reactive and water-insoluble metal oxide in an amount of about 0.001% to about 5% based on the total weight of the solution; and (C) a water-miscible to w

A process for preparing a solid water absorbing resin comprising mixing a solution of (A) acrylic acid neutralized 70-100 mole percent; (B) a non-reactive and water-insoluble metal oxide in an amount of about 0.001% to about 5% based on the total weight of the solution; and (C) a water-miscible to water-soluble polyvinyl monomer in a combined concentration of (A), (B) and (C) of at least 30 wt. %; with water to form a mixed solution wherein the monomers of the mixed solution consist essentially of (A) and (C) 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 metal oxide (B) and having a water content of 15 percent by weight or less.