High‐pressure phases in polymers. IV. Skeletal growth in cis‐polyisoprene

The crystallization of cis ‐polyisoprene even at moderately elevated pressures results in the formation of a single‐crystal species which develops through skeletal growth. The nature of these crystals, which are produced at relatively low supercooling, is described. They occur concurrently with spherulites but exhibit a much higher growth rate. In common with single crystals grown from solution the size and shape of the species is a function of the supercooling.