聚酰亚胺/聚苯胺-TiO2复合薄膜制备及表征

Preparation and Characterization of Polyimide/Polyaniline-TiO2 Composite Films

以4,4＇-二氨基二苯醚（ODA）和均苯四甲酸二酐（PMDA）为单体,以聚苯胺-二氧化钛（PANI-TiO2）为掺杂物,用原位聚合和超声振荡法制得聚酰胺酸/聚苯胺-二氧化钛溶液,经热亚胺化制得聚酰亚胺/聚苯胺-二氧化钛（PI/PANI-TiO2）复合薄膜。采用FTIR、SEM、TG-DTG、介电常数、电子万能试验机等对复合薄膜的结构、形貌和性能进行了表征与测试。结果表明：PI/PANI-TiO2薄膜的热亚胺化完全,PANI-TiO2粒子在PI基体中分布均匀。掺杂10%（以反应制得PI的质量为基准,下同）PANI-TiO2的PI/PANI-TiO2复合薄膜的综合性能优于纯PI,其拉伸强度由纯PI的14.8 MPa提高到43.8 MPa;初始分解温度由纯PI的435℃提高到518℃,800℃时的残炭量达到57.7%;介电常数由3.38提高到3.86,介电损耗由0.0013提高到0.0040。

Polyamic acid/polyaniline-titanium dioxide（PAA/PANI-TiO2） composite materials were prepared by in-situ polymerization and ultrasonic oscillation method with 4,4＇-oxybisbenzenamine（ODA） and pyromellitic dianhydride（PMDA） as monomers, PANI-TiO2 composite material as dopant, and further imidized into polyimide/polyaniline-titanium dioxide（PI/PANI-TiO2） composite films by heating process. The structure, morphology and properties of the obtained composite films were characterized by means of FTIR, SEM, TG-DTG, dielectric constant meter and universal mechanical testing machine. The results showed that the imidization of PI/PANI-TiO2 composite film was completely and PANI-TiO2 particles were evenly distributed in PI matrix. It was found that the PI/PANI-TiO2 composite film containing 10%（base on the mass of PI, as the below） PANI-TiO2 exhibited more excellent comprehensive properties than pure PI. The tensile strength was 43.8 MPa, higher than that of PI（14.8 MPa）. The initial degradation temperature increased from 435 ℃ to 518 ℃. The ratio of remaining carbon at 800 ℃ was 57.7%. The relative dielectric constant and the relative dielectric loss increased from 3.38 to 3.86 and 0.0013 to 0.0040, respectively.