Synthesis And Characterization Of Amino Acids Derived Chiral Poly(Amide-imids)s Bearing Dipeptide In The Main Chain

In this paper, a series of new chiral poly(amide-imide)s was designed and synthesized. The properties of the polymer were studied. A series of chiral diacids containing dipeptide was synthesized. Chiral amino acids, a common chiral substance were used as chiral source. After that a series of new chiral poly(amide-imide)s was synthesized by polycondensation reaction. Finally, the degradation of the polymer was explored.Various diacids based on chiral amino acid and pyromellitic dianhydride were prepared by a four-step reaction firstly. Such monomers containing peptide bond is due to introduction of a plurality of amino acids simultaneously. Monomer structures were characterized and confirmed by 1HNMR, FT-IR, elemental analysis. Characteristics of monomers were tested by DSC, automatic rotation and UV. A series of chiral poly(amide-imide)s was synthesized by polycondensation reaction with ODA. The structure of the polymer was confirmed by 1HNMR, FT-IR, elemental analysis. Optical properties of the polymers were studied by automatic rotation, FT-IR and UV. Thermal properties of the polymer were explored by DSC and TGA. The solubility of the polymer was research. Finally, degradation of the polymer was studied in phosphate buffer solution and soil suspension. Degradation results of the polymer powder were characterized by UV and FT-IR. Degradation results of the polymer film were characterized by SEM.A variety of target products were successfully synthesized in this experiment. The resulting monomers have a high purity. Melting process of monomer showed some peculiarities. The resulting polymer shows good optical properties. Specific rotation exhibits large differences with different structures. Polymer has UV absorption ability. Test results showed that Td10%>300℃, this shows that the polymer has good heat resistance. Polymer is insoluble in water and most organic solvents. This shows that the polymer has good solvent resistance. Polymer is soluble in polar aprotic solvents like N’N-dimethylformamide (DMF), N’N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP). This improves its workability. The degradation experimental results show that degradable of polymers containing different chiral amino acid has differences and selectivity. It also reflects the different biological activity of the polymer.