Nanolayer coextrusion of amorphous and semi-crystalline polymers for enhanced thermal and mechanical properties

Demand for polymer films with higher service temperature for use in modern industrial, automotive, and related applications has driven the development of novel composite materials. In this work, the storage moduli of PET (polyethylene terephthalate) and PPS (polyphenylene sulfide) were maintained and quantified up to 140 and 160°C respectively through nanolayer coextrusion processing against high T g COC (cyclic olefin copolymer) support layers. Layer multiplying coextrusion was leveraged to produce nanolayered cast films with COC layers ranging from 40 to 200 nm. The nanolayered films were able to maintain a 35–40% higher modulus, up to the glass transition of the continuous COC support layers, as compared to extruded blend films with an identical composition of high temperature glassy polymer. The results demonstrate leveraging polymer processing techniques to enable advanced high temperature performance of commercial polymer materials without the need for additives or additional polymer chain modifications enabling more rapid scaling to industrial adoption.