ON THE PROBLEMS CONCERNING THE METHOD OF EVALUATION OF CHAIN FOLDING

Changes in the processes of drawing and/or annealing of polyethylene films were clearly shown by Cf values as described in the previous reports. However, it was also found some anomaly that the Cf does not depend on lamellar thickness (long period). These results were found in comparison of Cf values of solution grown crystals with those of melt grown crystals. In this report two series of the specimens having different lamellar thickness were prepared. The one was solution grown lamellae crystallized at different temperatures and the other those thicken by annealing at different temperatures. The theoretical relationship between Cf and long period was found in the former but not in the latter. Another anomaly was found in a melt-quenched specimen which has low degree of crystallinity. From these results, it was considered that the anomaly would be attributed to the difference between the fold conformation of the lamellae crystallized from solution and that from melt.