Synthesis And Self-assembly Of Homopolymers And Diblock Copolymers With Rigid Polypeptide Chains

In this dissertation,firstly,the TPP-PBLG(TPP,tetraphenylporphyrin)were prepared and their self-assemble behavior were studied in detail.To the best of our knowledge,this was the first report that the porphyrin-terminated poly(?-benzyl-L-glutamate)and their self-assemble behavior.Secondly,the amphiphilic thermosensitive block copolymers PBLG-b-PEGMA(PEGMA,Poly(poly(ethylene glycol)methyl ether methacrylate))were synthesized and the self-assemble behavior and thermosensitivity were researched detailedly.It was predicted that this good biocompatible polypeptide copolymer PBLG-b-PEGMA may have great application prospect in biomedical field.The dissertation included these following parts:1.The 5-(4-Aminophenyl)-10,15,20-triphenylporphyrin(TPP-NH₂,a small molecule initiator for ring-opening polymerization with high efficiency)and a series of homopolymers TPP-PBLG(DP=100,80,64,52)were synthesized by controlling the mole ratio of initiator to monomer through NCA-ROP.The self-assemble behavior of TPP-PBLG was studied by changing conditions.Finally,the solid rod-like aggregate with different nanometer scale that could be precisely controlled and the solid ball-like aggregate were prepared.Those above assembly morphologies can be revealed by transmission electron microscopy(TEM),scanning electron microscopy(SEM)and atomic force microscopy(AFM),the change of the secondary structure and the optical property of TPP-PBLG during self-assembly were studied by ultraviolet visible absorption spectrum(UV-vis),fluorescence spectrum and circular dichroism spectrum(CD).2.The homopolymer Cu TPP-PBLG₁₀₀ was prepared by functionalizing TPP-PBLG₁₀₀ with Cu²⁺.The self-assemble behavior of Cu TPP-PBLG₁₀₀has no difference with TPP-PBLG₁₀₀ in the same system,which can be analyzed by SEM.This situation proved that the internal hydrogen bond of porphyrin has little effect on the self-assembled aggregates.The optical property was further investigated by UV-Vis and fluorescence spectrum.3.The PBLG_n-b-PEGMA₁₀₀(n=100,80,64,52)block copolymers were designed and synthesized via the combination of ATPR,amidation and click chemistry,the thermosensitivity and self-assemble behavior of PBLG_n-b-PEGMA₁₀₀were studied by UV-vis?SEM and TEM.The similar self-assembled aggregates(the solid ball-like aggregate and the solid rod-like aggregate)with membrane were prepared in the same condition.