Method for melt-molding water-soluble vinyl alcohol polymers
US5190712A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1991 |
| Grant date | Mar 2, 1993 |
| Priority date | — |
| Expiry date | Aug 30, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C2210/26
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for melt-molding a water-soluble vinyl alcohol polymer which includes melt-molding a water-soluble oxyalkylene group-containing vinyl alcohol copolymer under substantially anhydrous conditions and substantially without use of plasticizer, the copolymer having a vinyl alcohol unit (A), a vinyl ester unit (B) and an oxyalkylene ether unit (C) of the formulas: ##STR1## wherein R.sup.1 is an alkyl group; R.sup.2 and R.sup.3 each is a hydrogen atom or an alkyl group; R.sup.4 is a hydrogen atom, an alkyl group, a phenyl group or a substituted phenyl group; n is equal to 1 through 50; in proportions of a mol %, b mol % and c mol %, respectively, where EQU 0.1.ltoreq.c.ltoreq.20, EQU 50.ltoreq.100a/(a+b).ltoreq.100, and the oxyalkylene moiety (CHR.sup.2 --CHR.sup.3 --O--).sub.n of unit (C) accounts for 3 to 40 percent by weight of the total resin, and having a melt index of not less than 5 g/10 min. under a load of 2160 at a temperature of 210.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.