Process for improving the thermal stability of polyvinyl alcohol with a polymeric polycarboxylic acid
Abstract
Abstract THE THERMAL STABILITY OF POLYVINYL ALCOHOL IS IMPROVED BY MIXING A SUFFICIENT AMOUNT OF A POLYMERIC POLYCARBOXYLIC ACID SUCH AS POLYACRYLIC ACID, POLYMETHACRYLIC ACID, COPOLYMERS OF ACRYLIC ACID, METHACRYCLIC ACID OR MALEIC ACID CONTAOINING MORE THAN 10 PERCENT ACIDIC MONOMER, PROVIDED THAT SUCH COPOLYMERS OR THEIR SALTS ARE WATER SOLUBLE AT THE SPECIFIED PH LEVELS, AND VINYL METHYL ETHER/MALEIC ANHYDRIDE COPOLYMER, WITH POLYVINYL ALCOHOL TO CONVERT THE ALKALI METAL ACETATE CONTAINED WITH THE POLYVINYL ALCOHOL TO ACETIC ACID AND AN ALKALI METAL SALT OF THE POLYMERIC CARBOXYLIC ACID, SUCH THAT WHEN THE COMPOSITION IS MADE UP AS A 10 PERCENT SOLUTION IN WATER, THE SOLUTION HAS A PH OF FROM ABOUT 4.0 TO ABOUT 4.5.
Inventors
- 👤 P Subramanian
Bibliographic Details
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