Critical factors in polypropylene film used for pulsed power capacitors

Abstract

Isotactic polypropylene is a polyolefin with a helical structure involving at least 50 percent crystallinity [1]. This spiral structure results in a crystallized polymer of lower density than polyethylene. Polypropylene is a stereoregular polymer which is almost 100 percent isotactic in capacitor film applications [2]. Biaxial orientation of polypropylene film overcomes the tendency of polypropylene to fibrilate when oriented and is a major reason for use of such films in capacitors [3].