Claims
- 1. In a method of forming a polyurethane material by reacting a polyfunctional isocyanate with an active-hydrogen-containing material, the improvement characterized by including in the reactant mixture a crosslinked vinylidene chloride polymer microgel powder obtained by a method comprising the steps of
- (I) preparing a microgel latex by emulsion polymerizing (a) about 50 to about 90 parts by weight of vinylidene chloride, (b) about 10 to about 50 parts by weight of a copolymerizable ethylenically unsaturated comonomer, and (c) a minor amount of a copolymerizable crosslinking polyfunctional comonomer, wherein the microgels in the resulting latex have a gel content of about 25 to 99 percent and a second order transition temperature of at least about 30.degree. C., and
- (II) recovering the microgel powder from the latex;
- wherein the microgels prior to recovery have a diameter less than about 1 micron.
- 2. A method according to claim 1 wherein the gel content of the microgels ranges from about 50 to about 99 percent.
- 3. A polyurethane material prepared according to the method of claim 1.
Parent Case Info
This is a divisional, of application Ser. No. 942,512, filed Sept. 15, 1978 now U.S. 4,232,129.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
989911 |
Apr 1965 |
GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
942512 |
Sep 1978 |
|