Bulk polymerization process for preparing high solids and uniform copolymers

Claim 1

Bulk polymerization process for preparing enhanced yields of high solids, low molecular weight vinylic polymer product having a narrow molecular weight distribution and a low chromophore content comprising the steps of continuously: (a) charging into a continuous mixed reactor zone containing a molten resin mixture; (i) a mixture of vinyl monomers comprising at least one monoalkenyl aromatic monomer and at least one acrylic monomer; (ii) a polymerization initiator in amounts to provide a molar ratio of said initiator to said mixture of vinyl monomers from about 0.0005:1 to 0.04:1; (iii) from about 0 to 25 percent based on the weight of vinyl monomers of a reaction solvent, wherein said molten resin mixture comprises unreacted vinylic monomers and the vinylic polymer product; (b) maintaining a flow rate through said reaction zone sufficient to: (i) provide a residence time of said charged vinylic monomer mixture in said reaction zone of from about two minutes to one hour; and (ii) maintain a predetermined level of reaction mixture in said reaction zone, and; (c) maintaining the molten resin mixture at a reaction temperature within the range from about 180° C. to 270° C. sufficient to provide accelerated conversion to a readily processable, uniform, concentrated polymer product having a number average molecular weight of 500 to 6000, a polydispersity ratio of less than about 2.5 and a distribution index of less than about 4.5