Continuous process for making melt-processable optical grade ring-opened

Abstract

A continuous process for the solution polymerization of appropriate polycycloolefins in a ROMP zone to obtain a processable ROMP homo- or copolymer in solution, and subsequent hydrogenation of the ROMP (co)polymer without removing the residual ROMP catalyst and co-catalyst, provides an optical product having a mol wt M.sub.w in the range from 50,000-300,000 and polydispersity M.sub.w /M.sub.n in the range from 1.3-5.0, more preferably from 1.3-3, the lower the polydispersity the more desirable the physical properties of the (co)polymer. The process comprises, (A) continuously polymerizing a substantially anhydrous solution of said monomer by ring opening metathesis polymerization in at least a first and a last reaction zone of a multi-zoned, single-stage, reaction vessel to form an unsaturated polymer cement essentially free of unreacted monomer; (B) hydrogenating said unsaturated polymer cement in the presence of an effective amount of a nickel-containing hydrogenation catalyst in an amount sufficient to produce a hydrogenareal cement wherein more than 97% of double bonds in said unsaturated polymer are converted to single bonds; (C) removing more than 99% by weight of spent polymerization catalyst, used hydrogenation catalyst and filter aid present in said hydrogenated cement to produce an essentially solids-free hydrogenated cement; (D) devolatilizing said solids-free hydrogenated cement to produce a thickened hydrogeneated polymer cement, and, (E) recovering a solid polymer which meets particle count specifications for optical grade polymer.