Abstract: A process for preparing microgel(s) that uses a wide range of activatable prepolymers; in the process, a polymer composition of crosslinked component A and soluble components B and C is formed from mono-olefinic and multi-olefinic monomers in the presence of catalyst and initiator; the process comprises: I) introducing mono-olefinic monomer, catalyst, and initiator into a reactor in the absence of multi-olefinic monomer and producing an activatable prepolymer, component B; II) contacting the product of I) with multi-olefinic monomer to produce components A and C, optionally in the presence of additional initiator; also optionally in the presence of additional mono-olefinic monomer and initiator; the ratio of components A/(B+C) can be controlled by varying the mole ratio of Component B/ multi-olefinic monomer from 0.05/1 up to 5/1, by decreasing the mole ratio to increase the ratio of A/(B+C), and increasing the mole ratio to decrease the ratio of A/(B+C).
Type:
Grant
Filed:
July 9, 1999
Date of Patent:
March 12, 2002
Assignees:
E. I. du Pont de Nemours and Company, Commonwealth Scientific and Industrial Research
Organization, University of Melbourne, Australia
Inventors:
Charles T. Berge, Michael Fryd, Jeffrey W. Johnson, Graeme Moad, Ezio Rizzardo, Christopher Scopazzi, San Hoa Thang