Polymerization and copolymerization products (for ex ample, polyethylene, polytetrahxloethylenes, polyisobutyl· ene, polystyrene, polyvinyl chloride, polyvinyl acelate, polyvinyl chloroaceiale and other polyvinyl derivatives, polyacrylic and polymeihacrylic derivatives, coumaroneindene resins):
Produaos de polimeria adón y copolimcrizadón (polietileno, politetrahaloctileno, poliisobu· cileno, polieitircno, cloruro de polivinile, acetato de polivinilo, doroacetato de polivinilo y demi· derivados polivinilicoi, dcrivadoi poliacrílicoi y pol ι met acrilico*, resinai de cumaro­na­indeno, etc.):