COMPARISON OF LAMELLAR THICKNESS AND ITS DISTRIBUTION DETERMINED FROMDSC, SAXS, TEM AND AFM FOR HIGH-DENSITY POLYETHYLENE FILMS HAVING A STACKED LAMELLAR MORPHOLOGY

Lamellar thickness and its distribution in high-density polyethylene ( HDPE) films having a well-defined stacked lamellar morphology were inv estigated by using differential scanning calorimetry (d.s.c.), small-a ngle X-ray scattering (SAXS), transmission electron microscopy (TEM) a nd atomic force microscopy (AFM). It was found that the most probable lamellar thicknesses from SAXS and TEM agrees very well; however, they do not agree with those values obtained from d.s.c. and AFM. It is po inted out that the use of d.s.c. as a tool to determine lamellar thick ness and its distribution is so sensitive to the rate of heating in th e d.s.c. experiments and the parameters in the Gibbs-Thomson equation that it is not believed to be suitable for routine quantitative analys is. (C) 1997 Elsevier Science Ltd.