Mixing Behavior of D and H Components

In the present review, the crystallization behavior has been described for the D and H chains in the blend samples of DHDPE and LLDPE with various degrees of side 

This finding is quite important in the study of chain-folding mode in the lamella. The D and H chain stems are statistically randomly distributed in the lamella as clarified by the quantitative interpretation of the infrared band profile. The thermal data and the wide-angle and small-angle neutron scattering data also support this concept. Lrom all these data, we concluded that the PE chains show almost perfectly random reentry mode when crystallized from the melt, as far as a pair of DHDPE and LLDPE(2) is concerned. 

The study of cocrystallization is important also from the industrial point of view. Eor example, the two kinds of pipes, each made of a different kind of PE, are connected to make a water pipe. The strength of the connecting part of the two pipes is determined by the degree of cocrystallization of the two kinds of PE used. 

The concept deduced from the study of a parr of DHDPE and LLDPE(2) might not be applied as a universal concept to any other kind of PE pair. But the knowledge accumulated for the D/H blend samples described here should be basically important and useful for the structural study of any type of PE blend samples. 

The author wishes to thank Dr. Richard S. Stein and Dr. Shaw Lin Hsu of the Department of Polymer Science and Engineering, University of Massachusetts at Amherst, USA Dr. M. Satkowskii of Procter Gamble Co., USA Dr. Sono Sasaki of Japan Synchrotron Radiation Institute, SPring-8, Japan and Mr. Masaaki Izuchi, Mr. Kouji Imanishi, and Mrs. Gose Naomi of the Graduate School of Science, Osaka University, for their contribution in these smdies. 

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