Patent ID: 11879072
Assignee: LION COPOLYMERS HOLDINGS, LLC
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C | IPC C

Claim 12:
13. A styrene butadiene rubber latex composition made by a process comprising:
mixing a seed, a styrene, an initiator, a base, a surfactant, and a solvent to make a first mixture, wherein the first mixture has pH from about 4.0 to about 12.0;
adding a first portion of 1,3-butadiene to the first mixture to make a first reaction mixture;
heating the first reaction mixture to a temperature above 40° C. for a first reaction time from about 10 to about 24 hours to make a first styrene butadiene rubber latex, wherein the first styrene butadiene rubber latex has a viscosity from about 1 cP to about 500 cP;
mixing the first styrene butadiene rubber latex, a styrene, a base, an initiator, a surfactant, and a solvent to make a second mixture, wherein the second emulsion has a pH from about 4.0 to about 12.0;
adding a second portion of 1,3-butadiene to the second mixture to make a second reaction mixture; and
heating the second reaction mixture to a temperature above 40° C. for a second reaction time of from about 10 hours to about 24 hours to make a second styrene butadiene rubber latex, wherein the solids concentration is higher than that of the first solids concentration, wherein the second styrene butadiene rubber latex has a solids content greater than 50 wt %.