Preparation And Properties Of Poly(Aryl Ether Sulfone) Copolymers Containing Organo-siloxane And Biphenyl Structure In The Backbones

Poly(aryl ether sulfone)is a thermoplastic super engineering plastic with good mechanical properties,thermal stability,chemical resistance and outstanding low dielectric properties.By introducing a large volume of rigid biphenyl structure into the poly(aryl ether sulfone)material,the dielectric constant of the material can be effectively reduced(k=2.54),making it more widely used in the field of electronic appliances.As a kind of silicone polymer,polyorganosiloxane has great resistance to high and low temperature as well as aging,and has low polarizability and low surface energy,which can effectively reduce the dielectric constant of materials and improve the hydrophobic properties of the materials.Polydimethylsiloxane is the most widely used polyorganosiloxane,and has a helical molecular backbone composed of silicon-oxygen bonds.This structure gives the polydimethylsiloxane excellent chain flexibility.And due to the presence of silicon-oxygen bonds,the material has a lower polarizability and a low surface energy,which can effectively reduce the dielectric constant of the material while improving the hydrophobicity of the material.Polyhedral oligomeric silsesquioxane(POSS)is a caged organosiloxane possessing an inorganic core and an outer layer coated with organic groups.POSS combines the characteristics and advantages of organic and inorganic materials,and is the key research object of organic-inorganic hybrid materials.The silicon-oxygen cage structure of POSS gives the material outstanding thermal stability and chemical stability,and the organic groups on the outer layer ensure the material has good compatibility with organic polymer materials.At the same time,the low polarizability of POSS reduces the dielectric constant,and its low surface energy enhances the hydrophobic properties of the material.Due to the nanostructure of POSS,as it is introduced,the roughness of the surface of the material can be increased,and the hydrophobic property of the material can be further improved.In this paper,biphenyl structure and organosiloxane were introduced into poly(aryl ether sulfone)materials by chemical copolymerization to explore the synergistic effect of biphenyl structure with linear organosiloxane and cage organosiloxane on the thermodynamic properties,crystallization performance,hydrophobic properties,solubility properties and solubility effects of materials.The experimental results show that both the flexible chain polydimethylsiloxane and the large-volume cage POSS can reduce the dielectric constant of the material,improve the hydrophobic properties of the material,and maintain the thermal stability of the material to a certain extent.At room temperature,the DDSQ-containing biphenyl poly(aryl ether sulfone)polymer has a dielectric constant of at least 1.82,a hydrophobic angle of up to 122°,and a 5% weight loss temperature of more than 437 °C.