News in clear plastics & TPEs.

News in Clear Plastics & TPEs

A new continuous polymerization process to enhance the clarity and consistency of a series of acrylic copolymers, and new medical-grade thermoplastic elastomers are the two latest developments from Novacor Chemicals Inc., Leominster, Mass. (formerly Polysar Inc.). A redirection of the company's R&D efforts and the appointment of its first outside distributors are other news that emerged in a recent interview with company executives.

Novacor's Clear Performance Plastics group is employing a new polymerization process for its NAS 21, 30, and 50 lines of methyl methacrylate/styrene copolymers. Compared with the previous batch process, new continuous polymerization reportedly results in higher clarity. For example, internal haze of the NAS 30 grade has been lowered to below 0.2% from the previous 0.6%. In addition, internal color has been eliminated and thermal stability improved in this product.

Novacor's Sarlink TP Elastomers Div. also is introducing Sarlink 2400 TPE series, aimed at medical applications. The Sarlink 2400 series is available down to 40 Shore A hardness with low moisture and air permeability, low compression and tension set, according to the company. The 2400 series is approved for U.S.P. Class VI applications, making the material suited for medical applications such as blood vial stoppers. The company declined to identify the materials' composition. Other members of the Sarlink line are based on rubber-modified polyolefins and PVC/nitrile rubber blends.

SHIFTING DIRECTION

Clear acrylic-based copolymers and terpolymers and TPEs are now the focus of resin development for Novacor. The Zylar ST, NAS and Sarlink TPE lines now represent the flagship resins for the company, as Novacor has shifted its development efforts for the time being away from engineering thermoplastics.

Officials told PLASTICS TECHNOLOGY that Novacor quietly has discontinued marketing its Petsar glass-filled PET compounds and PET/polycarbonate alloys, as well as its SD-901 PC/acrylic alloy. All were first launched in the spring of 1989 (see PT, April '89, p. 13; June '90, p. 37). It's unclear whether the firm will revive these products in the future.

The Clear Performance Plastics group recently appointed its first two outside distributors for its NAS and Zylar lines. Performance Polymers Inc. of Leominster will be responsible for sales and technical support in 21 eastern and midwestern states. West Coast Polymers Inc., Long Beach, Calif., will service customers in 11 western states.