PMIA/蒙脱土纳米复合薄膜的制备与性能研究

Preparation and properties of PMIA/montmorillonite nanocomposite films

采用经十六烷基三甲基溴化铵有机改性的钠基蒙脱土(Na-OMMT)对间位芳香族聚酰胺(PMIA)进行改性,并采用刮涂法制得PMIA/Na-OMMT纳米复合薄膜,对复合薄膜的形貌结构及性能进行了表征。结果表明:当Na-OMMT质量分数小于等于1.5%时,Na-OMMT在PMIA基体中的分散性较好;当Na-OMMT质量分数为1.5%时,PMIA/Na-OMMT纳米复合薄膜的电压击穿强度为106.48 kV/mm,比纯PMIA薄膜提高了26.73%,表面电阻率为1.25×10^(14)Ω,体积电阻率为7.86×10^(15)Ω·cm,均比纯PMIA薄膜显著提高;随着Na-OMMT含量的逐渐增加,PMIA/Na-OMMT纳米复合薄膜的热膨胀系数减小,光学透过率逐渐减小,对紫外光的阻挡作用有较大提高,拉伸强度先增大后减小,当Na-OMMT质量分数为1.0%时,拉伸强度达到最大值,为108.12 MPa。

A meta-aromatic polyamide （PMIA） was modified by using cetyltrimethylammonium bromide-organically modified Na-montmorillonite （Na-OMMT） and was produced into PMIA/Na-OMMT nanocomposite film by scraping method. The morphology, structure and properties of the composite film were characterized. The results showed that Na-OMMT dispersed well in PMIA matrix when the mass fraction of Na-OMMT was not more than 1.5% ; as compared with pure PMIA film, PMIA/Na-OMMT nanocomposite film had the breakdown strength of 106.48 kV/mm with a growth of 26.73% and the profoundly improved surface resistivity of 1.25×10^14Ω and volume resistivity of 7.86×10^15Ω· cm when the mass fraction of Na-OMMT was 1.5% ; the thermal expansion coefficient of PMIA/Na-OMMT nanocomposite film was decreased, the optical transmittance was gradually decreased, the ultraviolet blocking effect was greatly improved, the tensile strength was firstly increased and then decreased when the Na-OMMT content was gradually increased; and the tensile strength was maximized as 108.12 MPa when the mass fraction of Na-OMMT was 1.0%.