抄録
Isothermal crystallization phenomena are studied by DSC and the X-ray diffraction method. The theoretical background of measuring the crystallinity, of the polymer during isothermal crystallization, by the X-ray diffraction method is presented. The monodisperse polyethylene fractions, which are prepared by a successive solutional fractionation run, are employed. It is strongly suggested by comparing the results obtained by DSC and the X-ray method that in the former method the role of secondary crystallization can never be overlooked and the change in the exponent n with the extent of crystallization, observed in DSC method, is not due to the molecular weight fractionation during crystallization.
