| 摘要 |
<p>1517408 Removal of water from aqueous polymer gels KYORITSU YUKI CO Ltd and MITSUBISHI CHEMICAL INDUSTRIES Ltd 26 Nov 1976 [26 Nov 1975] 49437/76 Heading C3P Water is removed from aqueous gels of watersoluble polymers having as a major component(s), repeating units of the formula wherein R<1> and R<2> are H or -CH3; R<3> is C1-3 alkylene; R<4>, R<5> and R<6> are the same or different and are C1-3 alkyl groups or benzyl; and X is an anion; in the presence of at least one compound selected from polyhydric phenols, benzoquinones, and derivatives thereof. Suitable compounds are catechol, resorcinol, pyrogallol, hydroquinone, benzoquinone and alkoxy substituted derivatives thereof including hydroquinone monomethyl or monoethyl ether. In the examples, the polymers are polyacrylamide and copoly(acrylamide/methacryloyl oxyethyltrimethyl ammonium chloride). Water is removed by simple heating (optionally under reduced pressure) or by azeotropic distillation.</p> |
