Petroleum processing by-product

• Rubber compound
• Volatile, water-insoluble liquid
• Hydrocarbon pioneers modified
• Synthetic-rubber ingredient
• Petroleum byproduct used to make synthetic rubber
• Liquid in synthetic rubber manufacture
• Hydrocarbon in rubber

Wikipedia Word definitions in Wikipedia
Isoprene , or 2-methyl-1,3-butadiene, is a common organic compound with the formula CH=C(CH)-CH=CH. In its pure form, it is a colorless volatile liquid. Isoprene is produced by many plants.

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Isoprene \I"so*prene\, n. [Etymol. uncertain.] (Chem.) An oily, volatile unsaturated hydrocarbon ( C5H8 ), obtained by the distillation of caoutchouc or gutta-percha, and used to make synthetic rubber by polymerization. In organic chemistry, it is viewed ...