Preparation And Properties Of High-performance Polymers Containing Azobenzene Groups In The Main Chain

(1)The light source has the characteristics of environmental protection,remote control and instant occurrence,and has become an ideal power source in the 21 st century.Light-responsive polymer materials have also become a research hotspot of responsive functional polymer materials.Among them,light-responsive polymer materials containing azophenyl groups have attracted much attention due to their wide application and excellent light-response performance.In recent years,based on the energy conversion characteristics of azophenyl group under the action of excitation light,the molecular geometric structure changes and the shape change occurs macroscopically,photodeformation of polymers containing azophenyl groups has become a hot research topic.The traditional photodeformable polymers containing azophenyl groups are mainly based on liquid crystal elastomers and liquid crystal crosslinking networks.Although they have good photodeformation properties,their mechanical properties and thermal stability are poor,which is not conducive to the Further application.So people introduced azophenyl groups to high-performance polymers such as polyimide and aromatic polyamide to prepare high-performance photodeformable polymer materials.This method expanded the use environment and temperature of the materials.However,there are currently few high-performance photodeformable polymer materials,the types of polymers need to be further expanded,and the research content needs to be further deepened.(2)In this paper,two high-performance new photodeformable polymer materials are prepared,which are polyaryl ether sulfones containing azophenyl groups in the main chain and crosslinked polyimide materials containing azophenyl groups in the main chain.We have studied the photodeformation properties and influencing laws of the prepared high-performance photodeformable polymers.(3)Polyarylether is a type of high-performance polymer with excellent comprehensive performance.We synthesized a novel bisphenol compound containing an azophenyl group,4,4'-dihydroxydiazophenyl ether.A series of azo was prepared by copolymerizing 4,4'-dihydroxydiazophenyl ether as the monomer and copolymerizing 4,4'-difluorodiphenyl sulfone and 4,4'-dihydroxydiphenyl ether Polyaryl ether sulfone copolymers with different phenyl group content.The thermal performance research results show that the main chain containing azophenyl group polyaryl ether sulfone copolymer has good thermal stability and high glass transition temperature.The results of photodeformation studies show that as the film thickness increases,the photobending rate of the polymer film decreases;as the content of the azophenyl group increases,the photobending rate of the polymer film increases;as the excitation light intensity increases The amplitude of polymer deformation increases.In addition,the photo-deformation rate of the polymer film under 442 nm laser irradiation is faster than under 532 nm laser irradiation.(4)The polyimide containing azophenyl group is currently the research hotspot of high-performance photodeformable azo-containing polymers.In order to further deepen research in related fields,we synthesized a polyimide polymer containing azophenyl groups in the main chain,and further used 1,4-p-xylylenediamine to crosslink it.The thermal performance research results show that the main chain containing azophenyl group polyimide has good thermal stability and high glass transition temperature.After cross-linking,the glass transition is steadily increased and the thermal stability is decreased.The results of photodeformation studies indicate that the photo-bending rate of the polymer film after cross-linking is increased compared with that before cross-linking.