Hemant B Parikh, 7260 William St, Perth Amboy, NJ 08863

5319041, Jun 7, 1994

Mar 26, 1993

8/038723

Yuanzhen Zhong - Wayne NJ
Hemant Parikh - Harriman NY
Paul D. Taylor - West Milford NJ
Terry E. Smith - Murray KY

ISP Investments Inc. - Wilmington DE

C08F 200
C08F 206
C08F 434
C08F 404
C08F22610
C08F21808

526 73

This invention relates to an improved process for producing a clear solution of vinylpyrrolidone (VP) and vinyl acetate (VA) monomers which comprises, in an anhydrous system, (a) reacting a C. sub. 2 to C. sub. 3 alcoholic solution containing said VA monomer and between about 60 and about 80 wt. % portion of total VP monomer in the presence of between about 0. 05 and about 0. 3 wt. % of a free radical initiator selected from the group consisting of tertamylperoxy pivalate and 2,2-azobis(2-methylbutyronitrile) or a mixture thereof for a period of from about 5 to about 10 hours, at a temperature between about 60. degree. and about 110. degree. C. ; (b) gradually adding the remaining VP monomer in C. sub. 2 to C. sub. 3 alcohol solution at reaction temperature after the addition of the VA monomer is complete; (c) raising the temperature of the resulting reaction mixture to between about 110. degree. and about 150. degree. C.

5395904, Mar 7, 1995

Dec 7, 1993

8/163446

Yuanzhen Zhong - Wayne NJ
Hemant Parikh - Harriman NY
Terry E. Smith - Murray KY

ISP Investments Inc. - Wilmington DE

C08F22610
C08F21808
C08F 434

526264

A process for making homogeneous copolymers of vinylpyrrolidone (VP) and vinyl acetate (VA) which form clear aqueous solutions and have high cloud points. The process involves precharging VP and VA monomers in a predetermined ratio, and then feeding VP and VA at a predetermined rate, the ratio of the components in the initial charge and the feeding rates for the monomer being selected in accordance with the reactivity rates of the monomers towards copolymerization as opposed to homopolymerization.

5844041, Dec 1, 1998

Aug 13, 1997

8/910127

Lowell Ray Anderson - Morristown NJ
Hemant Parikh - Harriman NY

ISP Investments Inc. - Wilmington DE

C08L 3700

524548

A process is described for increasing the viscosity and high humidity curl retention of aqueous solutions of homogeneous copolymers of 20-99% vinyl pyrrolidone (VP) and 1-80% N-3,3-dimethylamino-propyl methacrylamide (DMAPMA). The high viscosity solutions are particularly useful as the active component of hair care products.