A colorless volatile liquid, C5 H8 , used chiefly to make synthetic rubber.
A colorless, volatile liquid, CH2:C(CH3)CH:CH2, prepared by the dry distillation of raw rubber or synthetically: when heated with sodium or certain other substances, it polymerizes to form a substance closely resembling natural rubber.
A colorless, volatile liquid obtained from petroleum or coal tar and occurring naturally in many plants. It is used chiefly to make synthetic rubber. The isoprene in plants occurs in the chloroplasts and is used to build terpenes and other biologically important chemicals. Chemical formula:C5H8.
Coined (1860) by British chemist C. G. Williams, from iso- (“equal; different, isomeric”) + prop- (“three carbon prefix”) + -ene (“alkene suffix”). A misnomer.
When solid caoutchouc is strongly heated it breaks down, without change in its ultimate composition, into a number of simpler liquid hydrocarbons of the terpene class (dipentene, di-isoprene, isoprene, &c.), of which one, isoprene (C5H8), is of simpler structure than oil of turpentine (C 10 H 16), from which it can also be obtained by the action of an intense heat.
When this volatile liquid hydrocarbon (isoprene) is allowed ro stand for some time in a closed bottle, it gradually passes into a substance having the principal properties of natural caoutchouc. The same change of isoprene into caoutchouc may also be effected by the action of certain chemical agents.
At present the change of isoprene into caoutchouc is mainly of scientific interest in indicating possibilities with regard to the conversion of the liquid globules of the latex into rubber and to the formation of rubber by plants.
The exact manner in which isoprene passes into caoutchouc is also not understood.
These problems are, however, certain to be solved in the near future, and then probably caoutchouc may be formed in other ways than from isoprene.