Separation and purification of the saponified ethylene-vinyl acetate interpolymers

Abstract

Abstract WHEREIN R IS HYDROGEN OR METHYL, R'' IS -COOR, -C6H5, -CL, -CN, MELTHYL OR VINYL; THE RATIO OF (Y+Z):X IS WITHIN THE RANGE OF 1.5:1 TO 3:1 AND THE RATIO Z:Y IS WITHIN THE RANGE OF 0:1 TO 0.1:1 UNDER SUBSTANTIALLY ANHYDROUS CONDITIONS AND IN THE PRESENCE OF METHANOL WITH 0.005 TO 0.5 MOLES OF AN ALKALINE CATALYST, BASED ON THE MOL CONCENTRATION OF ACETIC ACID RADICAL IN THE INTERPOLYMER, THE DEGREE OS SPONIFICATION BEING AT LEAST 90 MOL PERCENT, WHICH COMPRISES: (A) ADMIXING WATER WITH SAID SUBSTANTIALLY AHYDROUS SOLUTION IN AN AMOUNT OF AT LEAST 5 WEIGHT PERCENT OF THE INTERPOLYMER UP TO AN AMOUNT WHICH DOES NOT CAUSE GELATION AND SEPARATION OF SAPONIFIED INTERPOLYMER IN SAID SOLUTION AT THE TEMPERATURE OF SAID SOLUTION, TO PRODUCE AN AQUEOUS METHANOL SOLUTION HAVING 15 TO 45 WEIGHT PERCENT OF SAID SAPONIFIED INTERPOLYMER, (B) SHAPING SAID SOLUTION OF SAPONIFIED INTERPOLYMER INTO A SHEET OR STRAND OF 1-10 MM. THICKNESS AND BRINGING SAID SHEET OR STRAND INTO CONTACT WITH AN AQUEOUS COAGULATING BATH TO FORM A GELLED MICROPOROUS SHEET OR STRAND, (C) WASHING SAID GELLED MICROPOROUS SHEET OR STRAND TO REMOVE THE REMAINING ALKALINE CATALYST AND ACETIC ACID SALT PRODUCED DURING SAPONIFICATION, AND (D) DRYING SAID WASHED MICROPOROUS SHEET OR STRAND. (H4C2)X-(CH2-CH(-OOC-CH3))Y-(CH2-C(-R)(-R''))N 1. A METHOD OF SEPARATING AND PURIFYING A SANPNIFIED ETHYLENE-VINYL ACETATE INTERPOLYMER FROM A SUBSTANTIALLY ANHYDROUS SOLUTION CONTAINING 25 TO 50 WEIGHT PERCEBT OF SAID INTERPOLYMER WHICH IS OBTAINED BY SAPONIFICATION OF AN ETHYLENE-VINYL ACETATE INTERPOLYMER HAVING THE GENERAL FORMULA:

Inventors

• 👤 K Nishioka
• 👤 R Tada
• 👤 K Sato

Bibliographic Details