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vinyl
tetrachloroethylene
vinyl chloride (chloroethene C2H3Cl)
polythene
polytetrafluoroethylene (PTFE), trademarked as Teflon
polyvinyl chloride (PVC)
polystyrene
Styrene
second of the ten Heavenly Stems 十天干[shí tiān gān]
turning stroke (in Chinese characters), aka 折[zhé]
alkene