| 摘 要： | The subject of the transition in linear polymer melt has been of particular interest since thediscovery of liquid crystal polymers.The transitions in several polymer melts have been recog-nized in recent years.These polymers are mainly rigid chain in nature and the transitions wereassigned as mesomorphic.Recently we have found a transition in the melt of tetrafluoroethylene-hexafluoropropylene copolymer (FEP copolymer). The authors~(1]) have found that the morphology of FEP copolymer is critically dependent onthe temperature of melt near 310?20?.When the melt was held at the temperature above itsmelting temperature and below 310?,the randomly arranged lamellas morphology was obtained.When the melt was held at the temperature above 320?,the spherulitic morphology was formed.When the copolymer crystallized from the intermediate temperature range,the rodlike morphologywas usually obtained.The variation of morphology with temperature can be easily detected by Small Angle Light Scattering technique.Also the crystallization curves,measured with the Per-
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