An experimental methodology to study polymer crystallization under processing conditions. The influence of high cooling rates

Abstract

A new experimental route for investigating polymer crystallization under very high cooling rates (up to 2000°C/s) is described. A complete and exhaustive description of the apparatus employed for preparing thin quenched samples (100-200. μm thick) is reported, the cooling mechanism and the temperature distribution across sample thickness is also analysed, showing that the final structure is determined only by the thermal history imposed by the fast quench apparatus. Details concerning the characterization techniques used to probe the final structure are reported, including density measurements and wide angle X-ray diffraction patterns. Experimental results concerning isotactic polypropylene, polyethylenetherephthalate and polyamide 6 are reported, showing the reliability of this experimental route to assess not only a quantitative information but also a qualitative description of the crystallization behaviour of different classes of semi-crystalline polymers.