الفهرس 
Literature survyOnly 14 pages are availabe for public view
 |  | from | 103 |  |  |
| | | from | 103 | | |
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.