Apr 20 2004
Recently patented organic PVC stabilisers invented by William and Mary Chemistry Professor William Starnes can make one of the world's most valuable and widely used plastics safer and more versatile. The development could reinvigorate the $1.8-billion vinyl additives market that has been disrupted by claims of PVC's adverse environmental impacts.
The technology, which employs unique organic compounds called ester thiols as heat stabilizers in PVC, or poly(vinyl chloride), offers an equally effective and more environmentally friendly replacement for current stabilizers, many of which contain heavy metals. In fact, the compounds Starnes has invented are so compatible with the vinyl polymer that they also serve as plasticizers when used at high levels.
Their dual benefit as both stabilizers and plasticizers could make ester thiols a near perfect solution for certain problems associated with PVC, namely questions about safety. In recent years, PVC has been the subject of much criticism from environmental groups regarding the use of potentially toxic stabilizers and plasticizers. But Starnes' patented ester thiols are safe, and just as effective as their counterparts.
"The potential here is immense." Starnes said. "If people throughout the world can use PVC without some of the concerns now associated with it, then literally, we're talking about saving lives, particularly in countries with less-strictly enforced environmental laws."
Found in vinyl siding, plastic flooring, shower curtains, plastic blinds, credit cards, packaging, children's toys, car parts, water pipes and other building materials, PVC shows up in nearly every area of normal daily life. In applications that involve human contact, PVC requires non-toxic stabilizers, which currently are not as effective as their toxic, metal alternatives. But Starnes' technology changes that model.
"There's absolutely no question that the technology works," he said.
Now, Starnes is working through Edison Polymer Innovation Corporation (EPIC) in Ohio, the same company he worked with to develop the technology, to license it. Already there has been significant interest in the innovation as stabilizers and as plasticizers from major specialty chemical companies.
Through the college's strong commitment to undergraduate research, William and Mary students regularly contribute to groundbreaking research such as the invention of ester thiols currently led by Starnes. He and his research team have several more patents pending in the United States and internationally, all related to the same class of organic compounds and PVC. Two other patents already have been given verbal approval. William and Mary's technology transfer program has helped Starnes during the patenting process, and as a result, the College will receive some portion of product royalties, should the invention be licensed. In turn, William and Mary would give a portion of that income back to the Chemistry Department. Prospects are very high, considering PVC is a world-wide, multi-billion dollar-industry.
Starnes, William and Mary's Gottwald Professor of Chemistry, has been with the College since 1989. Before joining Polytechnic University in Brooklyn in 1985, Starnes worked with Bell Labs, and previously, as the head of plastics additives research for ESSO, now known as Exxon Mobil.
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