聚偏氟乙烯流延膜的制备与性能
Preparation and Properties of Poly(vinylidene fluoride)Casting Films
夏琛 1李壮壮 2张博 1樊虎 1王宝 2潘鹏举2
作者信息
- 1. 浙江中烟工业有限责任公司,浙江 杭州 310009
- 2. 浙江大学化学工程与生物工程学院,化学工程联合国家重点实验室,浙江 杭州 310027;浙江大学衢州研究院,浙江 衢州 324000
- 折叠
摘要
含β晶体的聚偏氟乙烯(PVDF)的极性较强,是一种重要的压电和铁电材料,受到人们的广泛关注.在该工作中,选择了PVDF的3 种β晶体成核剂,首先用傅里叶红外光谱(FTIR)比较了 3 种成核剂对PVDF流延膜中β晶体含量的影响,随后选择成核效率最高的成核剂四苯基溴化膦(TPPB),通过调整流延工艺制备了高β晶体含量的PVDF流延膜,最后利用广角X射线衍射(WAXS)及小角X射线散射(SAXS)技术研究了PVDF流延膜以及其在后拉伸过程中的结晶结构,同时研究了流延膜的力学性能以及弹性回复性能等.研究结果表明,PVDF/TPPB流延膜的β晶体含量和片晶取向程度随着流延膜牵伸比的增加而增大.随着牵伸比的增加,PVDF/TPPB流延膜的屈服应力和杨氏模量增大,弹性回复能力增强.同时,在流延膜的后拉伸过程中,随着拉伸应变的增加,流延膜出现空洞结构,并且温度越低,空洞出现的临界应变越小,这对含β晶体PVDF微孔膜的制备具有指导意义.
Abstract
Poly(vinylidene fluoride)(PVDF)containing β crystals has strong polarity and is an important piezoelectric and ferroelectric material,which has received extensive attentions.In this work,three β-crystal nucleating agents were selected.Fourier transform infrared spectroscopy(FTIR)was used to compare the effects of three nucleating agents on the contents of β crystals in PVDF casting films.The results show that tetraphenylphosphonium bromide(TPPB)is the most efficient nucleating agent.The PVDF casting films with high β-crystal content were fabricated by adjusting the extrusion and stretching procedures.The crystal structures of the PVDF casting films and their post-stretching processes were studied by wide-angle X-ray scattering(WAXS)and small-angle X-ray scattering(SAXS).The mechanical properties and elastic recovery properties of the casting films were also studied.The results indicate that,with the increase of draw ratios,the β-crystal content and crystal orientation degree increase in the PVDF/TPPB casting films;the yield stress,Young's modulus,and elastic recovery also increase.During the post-stretching processes,cavities occur in the PVDF casting films with the increase of tensile strain.With the decrease of stretching temperature,the critical strain for the formation of cavities decreases,which benefits for the fabrication of PVDF-based microporous membranes containing β crystals.
关键词
聚偏氟乙烯/流延膜/拉伸性能/β晶成核剂/结晶结构Key words
Poly(vinylidene fluoride)/Casting Film/Tensile Property/β-Crystal Nucleating Agent/Crystal Structure引用本文复制引用
出版年
2024
NETL
NSTL
万方数据