ポリ三弗化塩化エチレンの結晶化度の分子量依存性

抄録

There are essential differences between polymer crystals and crystals of monomeric substances. From high polymers, macroscopic single crystals are scarcely formed; high polymers never crystallize completely but leave submicrocrystallites imbedded in amorphous matrix which is in “semicrystalline state”. The cause of this singular behaviour of high polymers has not been fully explained. The authors measured the crystallinity of polytrifluoroethylene of different molecular weights crystallized under most favourable conditions. The maximum crystallinity is found to increase linearly with the increase in molecular weight. In some extent, this is explained by assuming that the entanglement of polymer chains impedes the crystal development leaving amorphous regions and that the number of entanglements is proportional to the length of the chain. The cause of semi-crystalline formation of high polymers could thus be concluded as due to the entanglement of polymer chains.