Method for producing saponified ethylene-vinyl acetate...

Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...

Reexamination Certificate

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Details

C525S060000, C525S062000, C525S057000, C525S330600

Reexamination Certificate

active

07041731

ABSTRACT:
This invention provides a method for producing a saponified ethylene-vinyl acetate copolymer in which visible imperfections (particularly fish eyes) of the saponified copolymer is inhibited. In this invention, a mixture solution is prepared by adding water to a methanol solution after saponifying an ethylene-vinyl acetate copolymer, and insoluble materials are removed from this mixture solution. Various types of filter or centrifugal separator are used to remove insoluble materials. It is preferable that the weight ratio of methanol to water is from 5:5 to 9:1, the concentration of the saponified copolymer is from 30 to 60 wt %, and the temperature is from 55 to 80° C. This method is particularly suitable for producing a saponified ethylene-vinyl acetate copolymer having an ethylene content of 20 to 70 mol % and a saponification degree of at least 95 mol %.

REFERENCES:
patent: 2227997 (1941-01-01), Berg
patent: 2266996 (1941-12-01), Scott et al.
patent: 2386347 (1945-10-01), Roland
patent: 3290363 (1966-12-01), Saito et al.
patent: 3510464 (1970-05-01), Sato
patent: 3523933 (1970-08-01), Inskip
patent: 3541069 (1970-11-01), Bristol et al.
patent: 3544538 (1970-12-01), Masuda et al.
patent: 3847845 (1974-11-01), Tada et al.
patent: 3985719 (1976-10-01), Hoyt et al.
patent: 4485225 (1984-11-01), Satoh et al.
patent: 5292804 (1994-03-01), Chen
patent: 5744547 (1998-04-01), Moritani et al.
patent: 5866655 (1999-02-01), Fujiwara et al.
patent: 6288165 (2001-09-01), Moritani et al.
patent: 6653400 (2003-11-01), Kawahara et al.
patent: 1302286 (1973-01-01), None
patent: 47-38634 (1972-09-01), None
patent: 1-52404 (1989-11-01), None
patent: 6-345811 (1994-12-01), None
patent: 9-71620 (1997-03-01), None
patent: 10-158325 (1998-06-01), None
patent: 11-209435 (1999-09-01), None
JP 70034152 1970, Month is not available.

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