基于结晶特性调控的国产BOPP薄膜击穿性能提升研究OA

Biaxially oriented polypropylene(BOPP)film is the primary dielectric medium in film capacitors due to its high dielectric strength and low dielectric loss.However,most domestic polypropylene has high ash content and inadequate dielectric strength,creating heavy reliance on imported capacitor-grade polypropylene.This study modifies domestic high-ash BOPP film using a nucleating agent and conducts a multi-faceted comparison with imported low-ash BOPP film.By analyzing crystallization characteristics,it elucidates the microcosmic mechanism through behind the improved breakdown strength using nucleating agent.It also puts forward technical route for improving the breakdown performance of the high-ash domestic BOPP films.Results show crystallinity and grain size are key structural factors affecting the multi dimensional performance of the BOPP film.Compared to domestic BOPP film,the imported BOPP film exhibits higher crystallinity(44.05％)and smaller grain size(22.01 nm),yielding a room-temperature breakdown strength of 583.2 kV/mm(9.8％decrease at 100 ℃)and showing more excellent performance of breakdown,tensile stress and processing.After modification,the crystallinity of domestic BOPP film rises from 40.19％to 42.87％,while its grain size decreases from 24.89 nm to 21.21 nm.This significantly enhances its breakdown field strength to 576.8 kV/mm,with only an 8.0％reduction at 100 ℃,achieving performance comparable to the imported BOPP film.