聚酰亚胺/Al_2O_3纳米复合薄膜性能的研究

Study on the Properties of PI/nano-Al_2O_3 Composite Films

采用原位聚合法制备聚酰亚胺/Al2O3无机纳米复合薄膜,利用透射电镜(TEM)测试掺杂前Al2O3纳米颗粒的尺寸,采用X射线衍射(XRD)分析薄膜相结构,利用紫外光谱仪等测试方法研究组分对复合薄膜的紫外可见光吸收光谱、热稳定性和耐电晕老化时间的影响.研究表明:Al2O3纳米颗粒掺杂到PI复合薄膜后,颗粒尺寸无明显变化,Al2O3纳米颗粒掺杂良好,能够与聚酰亚胺高分子链形成有机/无机复合结构;复合薄膜的紫外光吸收率提高,出现吸收峰红移现象;随着Al2O3纳米颗粒含量的增加,薄膜的热分解温度和耐电晕老化时间先增大后减小,当Al2O3纳米颗粒的质量分数达到25%时,热分解温度最高,比纯PI薄膜提高20℃以上;耐电晕老化时间最长,达到纯PI薄膜的11倍.

Polyimide /nano-Al2O3（PI/Al2O3） composite films have been prepared via in-situ dispersive polymerization.The size of Al2O3 nanoparticles before doped was tested by TEM,and the phase structure of composite films is analyzed by XRD.The effect of content on the properties of PI /Al2O3 composite films（ultraviolet visible light absorption spectrum,thermal stability and resistance to corona aging time） was studied with multiple methods such as ultraviolet spectrograph.The results show that the size of Al2O3 nanoparticles adulterated in the composite films appears nearly unchangeable.Al2O3 nanoparticles doped well,and they can form organic /inorganic composite structure with polyimide polymer chains;With the increasing of Al2O3 doping concentration,the ultraviolet light absorption rates of composite films is improved,and the red shift takes place in absorption peak of composite films compared to PI film;The thermal decomposition temperature and corona-resistant aging time increases firstly and then decreases.When the content of Al2O3 nanoparticles reaches up to 25%,the thermal decomposition temperature of the composite films is higher than the pure PI film by 20 ℃,and the corona resistance time is 10 times higher than the pure PI film.