Semisuspension polymerization processes
AssigneeXerox Corporation
InventorsMichael K. Georges, Raj D. Patel
Life of this patent
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Abstract
Disclosed is a process for the preparation of a polymer which comprises effecting bulk polymerization of a mixture of at least one monomer, a free radical polymerization initiator, and a stable free radical agent until from about 10 to about 50 weight percent of the monomer has been polymerized; optionally adding additional free radical initiator; optionally adding a colorant; dispersing with a high shear mixer the aforementioned partially polymerized mixture in water containing a stabilizing component selected from the group consisting of non-ionic and ionic water soluble polymeric stabilizers to obtain a suspension of particles with an average diameter of from about 0.1 to about 10 microns; polymerizing the resulting suspension to form said polymer.
Claims42
A process for the preparation of a polymer comprising:
- effecting bulk polymerization of a mixture comprised of at least one monomer, a free radical polymerization inhibitor, and a stable free radical agent wherein the stable free radical agent is comprised of nitroxide stable free radicals selected from the group consisting of 2,2,5,5-tetramethyl-1-pyrrolidinyloxy free radical, derivatives thereof, 2,2,6,6-tetramethyl-1-piperidinyloxy free radical, derivatives thereof 2,2,4,4-tetramethyl-3-oxazolidinyloxy free radical, derivatives thereof and mixtures thereof until from about 10 to about 50 weight percent of the monomer has been polymerized to form a bulk polymerization product;
- optionally adding additional free radical initiator to said bulk polymerization product;
- optionally adding a colorant to said bulk polymerization product;
- dispersing said bulk polymerization product with a high shear mixer into water containing a stabilizing component selected from the group consisting of non-ionic and ionic water soluble polymeric stabilizers to obtain a suspension of particles or droplets comprised of said bulk polymerization product with said particles having an average diameter of from about 0.1 to about 10 microns;
- and
- polymerizing the resulting bulk polymerization product suspension in water to form said polymer.
Dependencies are inferred from the claim text.