三元共聚浅色透明聚酰亚胺薄膜的制备及性能表征

Preparation and Characterization of Ternary Copolymerization Light-colored Transparent Polyimide Films

采用两步法,以双环[2.2.1]庚烷二甲胺异构体混合物(NBDA)、2,6-二氨基甲苯(2,6-DAT)、4,4′-氧双邻苯二甲酸酐(ODPA)为原料,合成一系列不同比例二胺的浅色透明聚酰亚胺薄膜。通过红外光谱仪、紫外可见光谱仪、X射线衍射仪、差示扫描量热仪、静态热机械分析仪、热失重分析仪和万能材料试验机对薄膜进行表征分析。结果表明,薄膜已经亚胺化完全,整体为无定型结构,玻璃化转变温度(T_(g))随着2,6-DAT含量的增加而增大,最高可达268.46℃,热失重初始分解温度均在485℃以上,800℃残炭率最高为52.62%;在50~100℃温度范围内,热膨胀系数(CTE)最低为9.96×10^(-6)/℃,断裂伸长率在5.08%~8.26%范围内,具有良好的力学性能,薄膜在450 nm处的紫外透过率最高可达86.03%。

A series of light-colored transparent polyimide films with different ratios of diamines were synthesized by two-step method using a mixture of bicyclo[2.2.1]heptane dimethylamine isomers(NBDA),2,6-Diaminotoluene(2,6-DAT),and 4,4′-Oxydiphthalic anhydride(ODPA)as raw materials.The films were characterized and analyzed by infrared spectrometer,ultraviolet(UV-Vis)spectrometer,X-ray diffractometer,differential scanning calorimeter,static thermomechanical analyzer,thermal weight loss analyzer and universal material testing machine.The results show that the films have been completely imidized,the overall is amorphous structure,the glass transition temperature(T_(g))increases with the increase of 2,6-DAT contents up to 268.46℃,the initial decomposition temperature of thermal weight loss is above 485℃,the highest mass residual rate at 800℃ is 52.62%,in the temperature range of 50~100℃,the minimum coefficient of thermal expansion(CTE)is 9.96×10^(-6)/℃,the elongation at break is in the range of 5.08%~8.26%.The films have good mechanical properties,and the UV transmittance at 450 nm is up to 86.03%.