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Abstract A heat~reBi8tant rubber blen’d, (50 phr’* of nat Tal rubber O~R) a.nd 50 ph:ro:r ety’rene-butadiene rubber (SBR-1502) ) was prepared according to the standa.rd rubber techniques. Th.e bLend vas mix,ed ~ith different conee trat.ions and typ,es or carbon blacK:, namely” GPF and LAMPblack in o rde r to obtain a vide range of conductivity~ ’Fbe above vlI,lcanizates were sU:bjec~ed to electrical. conduc- ’t:lv:ity measurments at a wide rangeo! temperatures and eleotric ~1eldB. For the low concentrations of carboD black the temperature dependence of thee,lectrical conduo”tivi ty (v-) was found to obey the Arrhenioua relation ’wi”th an average value of tbe apllarent aot1vation energy of (0.97 eV) and. (0.56 eV)for LAJiP;<mt+S1Ui,) and GPFj(NR+SBR) reBpectivdy. Tl1e increase of the cal’hon blacll::co’ncentration resulted in a marked increaae of (er) due to the decrz-ease I’ll the in5ulating sepa.ration dis’tance (rubber matr.i:d betvee’n the ooni!u,ctive carbon ptl.rti,cln or aggregates. The variation. 0’1’ (0-) with T. in this case, reBelDble;a tla:t or metal.e. wi-ttl a negative va,lu,e of the tempera. ture co f:t~d:nto:l!ootidUl;lti. vi ty (Tee). _ ....• ----~ -------------- ””It Prt per hundered partll by weigh’!> of rubber. |