Guayule

Name:
Guayule
Detailed information:
A rubberlike hydrocarbon, almost identical with cis-polyisoprene, obtained from a shrub that is a member of the Compositae family. It is grown extensively in Mexico and the southwestern U.S. It contains approximately 15% rubber hydrocarbon in the form of latex in cells in the roots and stem. Conventional practice involves crushing and parboiling the entire plant; this coagulates the latex, which is removed by milling. An improved process utilizes steam from 200–240C for 6 min instead of milling. Resins, which comprise 10–15% of the plant, are then removed with acetone followed by treatment with hexane to extract the hydrocarbon. This method can increase the yield of hydrocarbon by up to 50%. The yield is 1 lb rubber/6 lb comminuted shrub.