共聚物链结构对共聚型含氟聚酰亚胺薄膜性能的影响

以4,4'-二氨基-2,2'-双三氟甲基联苯(TFMB)、4,4'-(六氟异丙烯)二酞酸酐(6FDA)和3,3',4,4'-联苯四甲酸二酐(BPDA)为反应单体，改变非含氟BPDA单体在二酐中的配比和加料方式制备出一系列共聚型含氟聚酰亚胺(PI)薄膜并表征和分析其性能，研究了共聚物链结构对其性能的影响。结果表明，BPDA单体的加料方式及其在二酐单体中的比例均影响薄膜的性能。共聚型含氟PI薄膜在室温下均溶于非质子极性溶剂，且在可见光范围内有较高的透光率。随着非含氟二酐单体BPDA含量的提高薄膜的光学性能略有降低而其热性能和力学拉伸性能提高。非含氟二酐单体占二酐单体的比例为68.97%的共聚型PI薄膜，在500 nm处的透过率达到96.01%；非含氟二酐单体占二酐单体比例为35.71%的共聚型PI薄膜失重10%的热分解温度为595.23℃，拉伸强度为100.98 MPa。同时，BPDA加料方式的改变对共聚型PI薄膜的光学性能、热学性能和力学拉伸性能均有不同程度的影响。

Effect of Copolymer Chain Structure on Properties of Fluorinated Copolyimide Film

4,4'-diamino-2,2'-bistrifluoromethylbiphenyl (TFMB), 4,4'-(hexafluoroisopropene) diacetic anhydride (6FDA) and 3,3',4 4'-biphenyltetracarboxylic dianhydride (BPDA) were used as the reactive monomer, a series of fluorinated copolyimide films were prepared by changing the proportion and feeding method of non -fluorinated monomer BPDA. The properties of the films were characterized and analyzed. The results show that both the feeding method and the proportion of BPDA in the dianhydride monomer can affect the properties of the films. The prepared fluorinated copolyimide films are soluble in the aprotic polar solvent at room temperature, and the film have a high light transmittance in the visible light range. As the content of non-fluorinated dianhydride monomer BPDA increased the optical properties of the film decrease slightly, while the thermal properties and mechanical tensile properties were improved. When the proportion of non-fluorinated dianhydride monomer is 68.97%, the transmittance of the prepared copolyimide film still maintains in 96.01% at 500 nm; When the non-fluorinated dianhydride monomer account for 35.71% of the dianhydride monomer, the thermal decomposition temperature at a weight loss of 10% of the prepared copolyimide film is 595.23℃, correspondingly the tensile strength is 100.98 MPa. The change of feeding mode of BPDA have different effect on the optical properties, mechanical properties and mechanical tensile properties of the copolyimide film.