| 摘要 |
<p>The processes for producing highly water absorptive resins of the present invention comprise the folling steps: (A) suspending an aqueous solution of partially neutralized alkali metal acrylate and optionally partially neutralized acrylamido alkane sulfonate in a hydrocarbon solvent containing a surfactant having a HLB value of 3∩6 or 8∩12; (B) subjecting the mixture to inverse suspension polymerization in the presence of at least one water soluble radical polymerization initiator; (C) if necessary, separating the moisture from the produced polymer by azeotropic distillation to reduce the water content to about 15 to 55 % by weight; (D) adding a crosslinking agent having two or more reactive groups such as epoxy groups, if desired, as a solution form to subject the surface of the polymer to crosslinking reaction; and optionally (E) subjecting to coagulation with the use of a coagulant in the presence of an inert solvent, whereafter drying the resultant coagulate to obtain the water absorptive resin.</p> |
