Recyclable Polyimine Resin And Its Carbon Fibre Composites

Thermosetting materials have excellent physical and mechanical properties,outstanding chemical stability owning to its permanent cross-linked network,which also caused the problems of recycling or reuse.There are serious drawbacks in the current recycling methods.The key to thoroughly solving the recycling problems of thermosetting resins is to develop the thermosetting polymers containing degradable groups,which is also called the intrinsic design method.Following this idea,we designed thermosetting polyimine based on dynamic covalent bonds.The synthesis of polyimine,the relationship between structure and properties,the recycling and degradation of polyimine molding product and its carbon fiber(CF)reinforced composites were studied and discussed in this paper.The main results and conclusions were summarized as follows:1 Two different types of Thermosetting polyimine PPHA-BAPP-TREN and PPHA-BAPPTREN with different properties were successfully synthesized by p-Phthalaldehdye(PPHA),2,2-bis[4-(4-aminophenoxy)phenyl] propane(BAPP),tri[(4-formylphenoxy)methyl]ethane(ARTA).2 The prepared BAPP-TREN polyimine molding product based on imine bond exhibits good hydrophobicity,outstanding thermostability,higher glass-transition temperature and excellent mechanical properties,meanwhile its re-healing,reprocessing,recycling and degradation were demonstrated with good results by physical and chemical methods.3 The performances of BAPP-TREN polyimine/carbon fiber(CF)composites were better than other analogous composites,the degradative products included low-molecular weight Schiff base and carbon fiber(CF)were obtained under certain special gentle conditions.The length,weave structure,chemical constitution and mechanical performance of carbon fibre cloth were perfectly preserved,and the raw material of the resin also can be reused.