化学改性对气体压力膨化孔洞聚丙烯膜的压电热稳定性和机电性能的影响

Influence of the chemical modification on the thermal stability of piezoelectricity and the electromechanical properties of pressure expanded polypropylene cellular electret film

通过压电d33系数等温衰减测量、热刺激放电（TSD）技术及介电谐振谱分析，研究了孔洞PP原膜及其化学改性膜在经历相同的压力膨化和热处理工艺后的压电热稳定性和机电性能。对比性地研究了90℃膨化和RT膨化对孔洞PP膜压电热稳定性和机电性能的影响。结果表明：化学改性及热膨化工艺改善了孔洞PP膜的压电热稳定性和机电性能，且90℃膨化改性膜比RT膨化改性膜具有更好的压电热稳定性和机电性能。

In this paper, the thermal stability of piezoelectricity and electromechanical properties were studied by measuring the isothermal decay of piezoelectric d33-coefficient and thermally stimulated discharge （TSD） current and analyzing dielectric resonance spectroscopy for the virginal and chemically modified cellular polypropylene （PP） films expanded and heat treated under the same conditions. The thermal stability of piezoelectricity and electromechanical properties of the PP films expanded at 90℃ or RT were investigated and compared. The results indicate that the thermal stability of piezoelectricity and electromechanical properties for the PP film were improved by chemical modification and pressure expansion with heat treatment, and that the modified film has better thermal stability of piezoelectricity and electromechanical properties, expanding at 90℃ than at RT.