Masterbatch Manufacturer Opts for Customizable Stabilizers to Address Phosphite Issues in Polyolefin Applications

Two products from a family of proprietary customizable stabilizers helped FD Plastics, a 51-yr old Canadian manufacturer (U.S. office in Leominster, Mass.) of additive masterbatches and color concentrates to reformulate masterbatches for polyolefins that overcame problems associated with phosphite antioxidants. Both products belong to the Baeropol Resin Stabilization Technology (RST) platform, commercially launched by Baerlocher, Cincinnati, Ohio, three years ago.

In the metallic stearate family, the RST component of these stabilizers have been shown to work synergistically with phenolic antioxidants and can either totally eliminate secondary antioxidant phosphites or reduce their use. By opting to use stabilizers based on this technology, FD Plastics addressed two challenges:

● Baeropol DRS 6812 was chosen to replace phosphite antioxidants in the company’s LLDPE-based masterbatch. FD Plastics had received customer feedback that high loadings of the previous masterbatch was causing the phosphite to plate-out on the processing equipment. This irritated workers’ hands caused by part rejects and interrupted production throughput due to the need for frequent cleaning.

The Baeropol antioxidant offered higher solubility and reduced airborne particles that can cause skin irritation as they are offered in low-dust sprayed prills. Moreover, RST can be used for generally recognized as safe (GRAS) applications, making it ideal for FD Plastics’ target products such as toys, maple syrup tubing and food packaging film. Too, Baerlocher’s extensive data on RST products avoided the need for additional testing. During over a year of supplying the new LLDPE masterbatch, FD Plastics has yet to receive a single complaint about plate-out.

● Baeropol T-1111, one of the Baerlocher’s T-Blend products—blended synergistic polymer stabilizers pre-formulated to reportedly provide superior stabilization for many polymer applications—was chosen to formulate a stabilization masterbatch for a customer producing high molecular weight LLDPE geomembranes for the mining and petroleum industries. Such critical geomembranes must withstand harsh temperature and chemical extremes and deliver extended useful life. The phenolic/phosphite antioxidant masterbatch FD Plastics had supplied to this customer for less demanding applications could not meet the ASTM D5885 OIT (Oxidative Induction Time) standard required for polyolefin geosynthetics.

FD Plastics developed a very highly-loaded masterbatch of Baeropol T-1111 that was tested by the geomembrane customer in an approval process requiring a number of scale-up production trials, with subsequent product testing. While this project is still in process, the customer approved the test results for Baeropol T-111, and FD Plastics has purchased the product to use in their LLDPE masterbatch. Products trials are the next step planned.