The Preparation And Blood Compatibility Properties Of Heparin-like Hyper-branched Polyimide

Polyimide which is a polymer containing cyclic imide groups in its main or side chains are heat-resistant, resistant to ozone, y-rays, and fast electrons and neutrons and posses excellent dielectric and mechanical properties. Hyper branched polymer had novel structure and unique properties, introducing hyper branched structure into polyimide was an effective way to improve the solubility. Moreover, cause the good gas permeability and selectivity of polyimide gas separation membranes, they have potential to apply to biomedical material. It is urgent to improve the blood compatibility of polyimide. Recently, the good blood compatibility of heparin-like polymer attracted many researchers'interests. There have been reports of the study of heparin-like polyimide. In this paper, we review the synthesis, structure and properties of polyimide. Besides, the synthesis and application of hyper branched polyimide and the anticlotting mechanism and preparation method of hearin-like polymer were also introduced in details.In this paper, hyper branched polyimide(HBPI) was synthesized via A2+B3 approach using 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA),4,4'-Oxydiphthalic anhydride(ODPA),2,2'-bis [4-(3,4dicarboxyphenoxy) phenyl] propane dianhydride (BPADA) and poly(oxyalkylene) triamine (ATA) as materials. The structure and properties of the products were characterized by fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), solubility test and X-ray diffraction, respectively. The chemical structure of such hyper branched polyimides were confirmed by FT IR spectra; It was found that the polymers had low-order aggregation structure with the d-spacing between 0.4055 nm and 0.4508 nm, which are less than the d-spacing of the normal Aromatic linear polyimides; The solubility test showed that the obtained polymers were soluble in several polar aprotic solvents; The resulting hyper branched polyimides performed thermal stability with the initial thermal decomposition temperature above 300℃in N2.Hyper branched copolyimides were synthesized via A2+B3 approach using 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA),4,4'-Diaminodiphenyl ether(ODA) and poly(oxyalkylene) triamine (ATA) as materials. The structure and properties of the products were characterized by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and solubility test. It was found that PI's 5% or 10% thermal decomposition temperature in N2 increased as the proportion of ODA increased; The solubility test showed that the obtained hyper branched copoly(amic acid)s were soluble in several polar aprotic solvents, but the solubility of hyper branched copolyimides that prepared through thermal imidization is weak.In this paper, heparin-like hyper branched polyimide was synthesized using 2,2'-bis [4-(3,4dicarboxyphenoxy) phenyl] propane dianhydride(BPADA),1,3-propane sultone, N,N-Dimethyl-1,3-diaminopropane(DMAPA) and poly(oxyalkylene) triamine (ATA). The structure and properties of the products were characterized by fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectrum (NMR), X-ray diffraction(XRD) and thermal gravimetric analysis (TGA), solubility test, coagulation time and recalcification time tests in vitro and hemolysis test. The chemical structure of such hyperbranched polyimides were confirmed by FT-IR spectra. It was found that the coagulation time and recalcification time of heparin-like hyper branched polyimide was longer than that of hyper branched polyimide, and its hemolysis ratio is 3.5%, which is less than 5%.