Study On Synthesis And Properties Of Novel Polyamides With Solubility And High Heat-resistant

Aromatic polyamides as high performance polymers are widely referred in the automotive manufacturing,electronic appliances,machinery and equipment and other fields due to its excellent heat resistance,chemical stability,corrosion resistance and weather resistance,excellent mechanical properties,excellent electrical insulation properties,outstanding self-lubricating properties and abrasion resistance.However,due to the strong interaction between PA molecular chains,the rigidity of the macromolecules inherent in the main chain,and the crystalline or semi-crystalline aggregation structure of the polymer,etc.,the aromatic polyamides are difficult to be dissolved and difficult to melt,thereby further limiting its application.In order to overcome the above drawbacks,researchers have made a great deal of effort,such as improving the polymer solubility and processing conditions through molecular structure modification,while maintaining its high thermal stability,thereby further expanding its application field.In the dissertation,the recent progress on the study of polyamides and fluoridated polyamides was introduced.Research work was mainly composed of three parts as follows:1.A novel diamine monomer 4-(4-(1-morpholinyl)phenyl)-2,6-bis(4-aminophenyl)pyridine(MPAP)was prepared by 4-morpholinobenzaldehyde and 4-nitroacetophenone through a modified Chichibabin reaction obtained.A series of aromatic polyamides were obtained by Yamazaki phosphorylating condensation method with aromatic dicarboxylic acids,such as terephthalic acid,isophthalic acid,and 4-(4-carboxyphenoxy)benzoic acid.Then the structure and properties of the polyamides were characterized and the results shown that the type of polyamide films have excellent heat resistance,good solubility,optical properties,and mechanical properties.2.A novel diamine monomer 4-(4-(tert-butoxy)phenyl)-2,6-bis(4-aminophenyl)pyridine(TPAP)prepared from 4-tert-butoxybenzaldehyde and 4-nitroacetophenone through a modified Chichibabin reaction obtained.A series of aromatic polyamides were obtained by Yamazaki phosphocreatine condensation method with aromatic dicarboxylic acids,such as terephthalic acid,isophthalic acid,and 4-(4-carboxyphenoxy)benzoic acid.The results show that polyamide film containing t-butyloxyphenyl and heterocyclic pyridine has excellent heat resistance,good solubility,optical properties and mechanical properties,and the resulting polyamide agglomerates.3.The novel diamine monomer 4-(3-methoxy-4-(difluoromethoxy)phenyl)-2,6-bis(4-aminophenyl)pyridine(MFPAP)was synthesized from 3-methoxy-4-difluoromethoxybenzaldehyde and 4-nitroacetophenone.A series of fluoridated aromatic polyamides were obtained by Yamazaki phosphocreatine condensation method with aromatic dicarboxylic acids,such as terephthalic acid,isophthalic acid,and 4-(4-carboxyphenoxy)benzoic acid.The results show that polyamide film containing fluorine-containing oxygen and heterocyclic pyridine have outstanding heat resistance,good solubility,optical properties and mechanical properties.