Heading No. 39.02 of the Tariff and Customs Code provides: 39.02 ??? Polymerisation and copolymerisation products (for example, polyethylene, polytetrahaloethylene, polyisobutylene, polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl chloroacetate and other polyvinyl derivatives, polyacrylic and polymethacrylic derivatives, coumaroneindene resins).