After the graft eopolymer of styrene-divinyl benzene．rubber had been extracted first with petroleum ether and then with a mixture of methyl ethyl ketone and me-thanol in the soxhlet extractor in order to get rid of the linear polymer，the degree of unsaturation was determined．From the experimental results．it was shown that the degree of unsaturation in the graft eopolymer of S-DVB-R was not decreased．The graft eopolymer which，having been extracted，possesses higher swelling eoef-ficient tjlan that of the eopolymer of S-DVB Was ehlVromethylated and amlnated by the ordinary method． It was discovered that it tovk a longer time for the ehlorome．thylation of copolymer containing rubber than that，it did nbt contain any．The pro-duct thus obtained was tested for meehanical strength under wet condition．it was found that the gran

ular particles with an average diameter of 0.64 mm were not bro-ken until an average weight of 700 g was added on．They also had a better elasticdty

and tenaeity．By the indica

tvr method，the exchange velocity of the ffewly prepared resin was ditermined with hydrochloric acid．The diffusion coefficient was calculated according to the method adopted by Reiehenbery．The result showed that the new resin posses．ses la．higher diffusion eoefficient．The new resin also possesses higher water content and lower density than those of the vrdinary resin．