Assertion: rubber | /r/HasProperty | polyisoprene
Facets:
Source sentences:
text: Following its introduction to Europe from the New World in the late 15th century, natural rubber (polyisoprene) was regarded mostly as a fascinating curiosity.
text: Much of the butadiene rubber produced is blended with natural rubber (polyisoprene) or with styrene-butadiene rubber to give it improved resilience and lower rolling resistance.