聚酰亚胺-b-聚脲共聚物薄膜的制备研究

发布时间：2018-04-25 09:23

  本文选题：聚酰亚胺 + 聚脲　； 参考：《大连理工大学》2016年硕士论文

【摘要】：聚酰亚胺(PI)因其优异的热稳定性、力学性能、电性能以及化学稳定性被广泛应用于航空航天、电子电气、机械、化工等高新技术领域。随着科学技术的蓬勃发展,微电子行业对聚酰亚胺材料的吸水性能提出了更高的要求,传统的芳香族聚酰亚胺材料已经不能满足微电子行业不断发展的要求。因此,开发新型低吸水率聚酰亚胺材料具有十分重要的意义。众所周知,聚脲(PUA)的力学性能和热稳定性较好,且吸水率较低,若将其与聚酰亚胺共聚,有望在保持聚酰亚胺本身优异性能的前提下,降低聚酰亚胺的吸水率。本课题通过溶液聚合的方法合成了聚酰亚胺-b-聚脲(PUI)共聚物。具体方法为：将酸酐终止的聚酰胺酸(PAA)溶液与异氰酸酯终止的聚脲溶液混合,加入交联剂进行交联反应,之后经过热亚胺化处理制备了PUI共聚物薄膜,并对该薄膜的性能进行了研究。主要研究内容如下：首先,以均苯四甲酸二酐(PMDA)和4,4’-二氨基二苯醚(ODA)为单体,在N-甲基吡咯烷酮(NMP)溶剂中进行溶液聚合,制备酸酐终止的聚酰胺酸溶液,并探究单体配比、加料顺序、反应温度、反应时间、反应物总固含量对聚酰胺酸特性粘数的影响；其次,以二苯基甲烷-4,4'-二异氰酸酯(MDI)和ODA为单体,在NMP溶剂中进行溶液聚合,制备异氰酸酯终止的聚脲预聚体溶液；第三,将聚酰胺酸溶液与不同含量的聚脲溶液混合,再加入一定量的ODA进行交联,然后通过亚胺化处理得到PUI共聚物薄膜。最后,通过FTIR、XRD、SEM、TGA分析对PUI薄膜进行表征,探究了聚脲的含量对PUI接触角和吸水率的影响。研究发现,制备的PUI共聚物薄膜具有良好的疏水性能,并且随着聚脲含量的增大,PUI共聚物的接触角越大、吸水率越低。当聚脲的含量为50mol%时,PUI共聚物薄膜的接触角为101.56°,吸水率为1.16%。另外,PUI的热稳定性较好,其热分解温度在240～245℃之间。
[Abstract]:Polyimide (Pi) has been widely used in aerospace, electronic and electrical, mechanical, chemical and other high-tech fields due to its excellent thermal stability, mechanical properties, electrical properties and chemical stability. With the rapid development of science and technology, the microelectronics industry has put forward higher requirements for the absorbability of polyimide materials. Traditional aromatic polyimide materials can not meet the requirements of the development of the microelectronics industry. Therefore, it is of great significance to develop new low water absorption polyimide materials. It is well known that the mechanical properties and thermal stability of polyurea (PUAA) are good, and the water absorption is low. If copolymerized with polyimide, it is expected to reduce the water absorption of polyimide on the premise of keeping the excellent performance of polyimide itself. In this paper, polyimide-b-polyurea (PUI) copolymers were synthesized by solution polymerization. The specific methods are as follows: the polyamide acid acid (PAA) solution terminated by anhydride is mixed with the polyurea solution terminated by isocyanate, crosslinking reaction is carried out by adding crosslinking agent, and then the PUI copolymer film is prepared by thermal imidization. The properties of the films were also studied. The main research contents are as follows: firstly, the polyamide acid solution terminated by acid anhydride was prepared by solution polymerization in N-methylpyrrolidone (NMPP) solvent with PMDAs and ODAs as monomers, and the monomer ratio was investigated. The effects of feeding order, reaction temperature, reaction time and total solid content of reactants on the intrinsic viscosity of polyamide acid were studied. Secondly, the solution polymerization was carried out in NMP solvent with diphenyl methane-4 (4) -diisocyanate diisocyanate (MDI) and ODA as monomers. The polyurea prepolymer solution terminated by isocyanate was prepared. Thirdly, the polyamide acid solution was mixed with the polyurea solution with different content, then crosslinked with a certain amount of ODA, then the PUI copolymer film was prepared by imidiation. Finally, the PUI films were characterized by FTIR TGA, and the effects of polyurea content on the contact angle and water absorption of PUI were investigated. It is found that the prepared PUI copolymer films have good hydrophobicity, and with the increase of polyurea content, the higher the contact angle of the copolymers, the lower the water absorption. When the content of polyurea is 50 mol%, the contact angle is 101.56 掳and the water absorption is 1.16 掳. In addition, the thermal stability of PUI is better, and its thermal decomposition temperature is between 240 鈩，

本文编号：1800720