US custom compounder Teknor Apex (Pawtucket, Rhode Island; www.teknorapex.com) has developed flexible vinyl compounds with plasticisers based on renewable resources for applications ranging from automotive window encapsulation to medical tubing and footwear. “BioVinyl” compounds are already in commercial use in “flip-flop” sandals produced in the US, a range of shoe welting and a new series of “Tuff-Seal” interlocking floor tiles.

The compounds incorporate phthalate-free “Ecolibrium” bio-based plasticisers, manufactured using plant by-products by the Electrical and Telecommunications (E&T) unit of chemical giant Dow (Midland, Michigan / USA; www.dow.com). Under a joint collaboration agreement – see Plasteurope.com of 30.01.2012 – Teknor Apex has been granted the exclusive right to market flexible vinyl compounds containing “Ecolibrium” bio-based plasticisers in certain applications in North America. Life cycle analysis tests indicate that the use of “Ecolibrium” helps reduce carbon dioxide equivalent emissions by 41%.

Potential applications include automotive window seals, interior and exterior trim and instrument panel skins, medical tubing, masks, collection bags and consumer products such as footwear and toys.

“Because half of the PVC polymer is derived from seawater and typical plasticiser loadings are 33%, the substitution of the new plasticisers for conventional phthalates makes the carbon footprint of BioVinyl compounds dramatically smaller than that of many plastics,” said Teknor Apex business development manager Michael Roberts.

The company said the most pronounced property change discovered in comparison with conventional phthalate-plasticised compounds was an improvement in heat stability, enabling extrusion processors to carry out longer product runs without prohibitive levels of polymer degradation.