Research On The Polymerization Based On Isocyanides

Isocyanides,as important compounds for synthesis of nitrogen-containing materials,have been widely used both in heterocyclic chemistry and in multicomponent reactions.With the continuous progress of research on the organic reaction of isocyanides,people have tried to apply such compounds to synthesize polymer materials with heteroatoms.In recent years,only a few research groups have devoted themselves to the study of the polymerization on isocyanides,which mainly focus on the active/control polymerizations,or the multicomponent polymerizations,etc.But the species of polymers,lacking of diversity,are limited to polyisocyanides,polyesters or polyamides.There are still a large number of isocyanides-based polymerizations to be discovered.Therefore,it is very important to develop a novel polymerization based on isocyanides and prepare polymers with novel structures.In the second chapter,we developed a polymeric methodology for the preparation of polycarbodiimides based on isocyanides and azides.Via systematic optimization of polymeric conditions,polycarbodiimides were prepared in excellent yields(up to 93%),which possess good thermal stability,high weight-average molecular weights(up to 75 000 g/mol),and high refraction index(1.8691-1.6444).Moreover,the polymers could be easily post-modified via carboxylic acid towards functional poly-N-acylureas(PAUs).Also,PAUs could be prepared through one-pot multicomponent tandem polymerizations(MCTPs)of isocyanides,azides and n-butyric acid.Besides,due to the introduction of tetraphenylethene moiety,the resulting polymers emerged aggregation-enhance emission(AEE)characteristic.Hence,this work not only established a polymerization towards polycarbodiimides,but also provided a strategy for preparing poly-N-acylureas.In the third chapter,we successfully developed the multicomponent polymerization of isocyanides,disulfonyl azides and aromatic diamines.The reaction was carried out in air atmosphere at 80 ℃ for 1 h to obtain poly(sulfonyl guanidines)in the yield of 99% with molecular weights up to 39 800 g/mol.In the future,based on the properties of isonitrile monomers,we can develop more isocyanides-based polymerization reactions to produce more excellent and colorful polymer materials.