Preparation Of Poly (Aryl Ether Ketone) Containing Furan Side Group And Its Application In Repairable Thermosetting Materials

Thermosetting materials have stable cross-linking structure,excellent properties and a wide range of applications,but they are insoluble and difficult to recover and reprocess after curing and crosslinking.The processability of thermosetting materials can be improved by introducing dynamic covalent bonds,make it recyclable and repairable.Thermally reversible Diels-Alder reaction is one of the commonly used methods,which is often used to prepare repairable materials.Therefore,in this thesis,starting from the introduction of controllable furan groups in the poly(aryl ether ketone)side chain,poly(aryl ether ketone)with pendent furan benzene were prepared,and the conjugated double bonds of furan groups in the polymer were used as dienes and carbon nanotubes as dienophiles to carry out Diels-Alder reaction to explore the poly(aryl ether ketone)with pendent furan benzene to be used as repairable thermosetting materials.Firstly,2-(4'-aminophenyl)-hydroquinone monomer was synthesized by diazo salt coupling and reduction method.The results of DSC,NMR and IR showed that the monomer with high purity was successfully synthesized.A series of poly(aryl ether ketone)with pendent amino benzene were prepared by nucleophilic polycondensation of the synthesized monomers.The structure of the polymer was proved by NMR and IR,and further proved by UV analysis.DSC results show that the glass transition temperature of the polymer containing amino benzene side group increases with the increase of amino content.A series of poly(aryl ether ketone)with pendent furan benzene were prepared by amidation of poly(aryl ether ketone)containing amino benzene with furoic acid.The structure of the prepared polymer was proved by NMR and IR,and further proved by UV spectrum.The DSC results show that the glass transition temperature of poly(aryl ether ketone)with pendent furan benzene with the same side group molar content is higher than that of poly(aryl ether ketone)with pendent amino benzene,and increases with the increase of furan group content.TGA analysis shows that the polymer has good thermal stability,and its 5% thermal weight loss temperature is above 440?,but the thermal stability decreases with the increase of furan molar content in the polymer.Finally,multi-walled carbon nanotube(MWCNT)/ poly(aryl ether ketone)with pendent furan benzene composites were prepared by solution blending and sol-gel method,and the composites were heat-treated at high temperature to make them cross-linked and cured.The effects of different heat treatment temperatures on the thermal properties of the materials were studied.Through the SEM spectrum,it can be seen that MWCNT are uniformly distributed in the polymer matrix,showing good dispersion and interfacial compatibility;the TGA curve of the composite shows that the composite has excellent thermal stability.The dynamic mechanical properties of the composites were studied by DMA.The change of dynamic thermomechanical properties showed that the Diels-Alder reaction occurred between MWCNT and furan groups in the polymer matrix.It was proved that the reverse Diels-Alder reaction could be realized at a certain temperature and the material could be repaired.