Synthesis And Properties Of New Thermosetting Polymers Containing S-Triazine And Phthalocyanine Units

Thermosetting resins are generally cross-linked polymers formed by small molecule or oligomers with two or more functional groups at certain temperatures.The resulting resins generally exhibit lighter weights than metal materials and higher stability than linear polymers.In this thesis,a series of new thermosetting resins containing s-triazine and phthalocyanine moieties with high heat resistance were synthesized,and we discussed the monomer structure design,synthesis route and performance of polymers in detail.1.Perfluorocyclobutyl(PFCB)aryl ether resins based on s-Triazine core monomersIn recent years,new triazine resins derived from cyanate ester resins have been widely used in the aerospace and electronic and electrical fields due to their facile synthesis method,good heat resistance,processability and dielectric properties(low dielectric constant and low dielectric loss).We designed and synthesized two monomers with two different connection fashions(triazine ring and benzene ring are connected by C-O-C or C-C patterns)with triazine ring as the cores and trifluorovinyl aryl ether as the cross-linkable group.The synthetic route was optimized,and the influence of different connection fashions on polymer properties was discussed emphatically.The results of thermogravimetric analysis,thermomechanical analysis,and dielectric analysis verified that both resins have low dielectric constant and high thermal stability.2.The bio-based phthalocyanine resins derived from vanillinPhthalocyanine resins have attracted widespread attention in the material industry since they were discovered because of their excellent heat resistance.However,most of the precursors of phthalocyanine resins have disadvantages such as poor solubility,high melting point,and difficulty in curing,therefore the monomer structure design and the catalyst selection are hot topics.At present,the phthalocyanine resins that are widely used in the aerospace field are almost cured from the monomers prepared from petroleum-based chemicals with p-nitrophthalonitrile.With the continuous decreasing of petroleum reserves,it is urgent to find renewable resources to replace petroleum-based products.In this thesis,the renewable biomass vanillin was used as the feedstock to obtain vanillin-based phthalonitrile monomer through a simple two-step reaction at ambient temperature.In addition,the hydroxyl group of vanillin plays an important role in catalyzing the curing process.This new bio-based phthalocyanine resin has high heat-resistant with a carbon yield of up to 76%.