Natural rubber is a kind of high molecular compound which take gathered isoprene as the main component , molecular formula is n (C5H8), rubber hydrocarbon (poly (isoprene)is of  91% ~ 94% content ,the rest are Protein, fatty acids, ash content,suger,and other materials that are not rubber , natural rubber is the most widely used general-purpose rubber.

Generally for solid of flake, relative density is 0.94, the refractive index is 1.522, elastic membrane is 2 ~ 4 mpa, softening during 130 ~ 140, gluely softening during 150 ~ 160, beganing to degrade elastic from 200, under the normal temperature resilience is relatively high, and a little plasticity, crystallization at low temperature ,and has good alkali resistance, but not resistant to strong acid insoluble in water ,low-levelAcetone andalcohol can swelling innonpolar solvent ,such asChloroform and carbon tetrachloride.

 

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