Synthesis And Characterization Of Biodegradable Poly-esteramide With Ether Linkage In The Backbone Chain

Aliphatic polyesters such as PLA, PGA and PCL attract most studies in biodegradable polymers. Because of the hydrophobicity and crystallinity of the polymer, the degradation speed of homopolymer can not be controlled easily and restrict the application of them. Copolymerization and modification is often carried out to ajust the components and proportion of the polymer to control the .polymer's physical morphology, hydrophilicity, hydrophobicity, degradation rate, mechanism performance and other properties.A series of biodegradable polyesteramides having ether linkages in the main chain have been synthesized by ring-opening polymerization by 3-morpholinone(M) and E-caprolactone(CL) in bulk using zinc powder as catalyst. The effect of reaction conditions on the monomer convertion and copolymer molecular weitht has been investigated. The result showed that the optimal reaction temperature was 120℃; the optimal duration of reaction was 24h; the optimal ratio of m(M)/m(I) was 50:1; the optimal ratio of n(M)/n(CL) was 1:2. Under the optimal condition the polymer whose Mn was 13 509 could be obtained while the weight yield was 79%. The polymer was characterized by 'H NMR, GPC and FT-IR. The reactivity ratio of CL(1.20) and M(0.79) in the copolymerization was calculated via Fineman-Ross equation. The increasing of M content in the copolymer could enhance its hydrophilicity and thus result in a greater water absorption rate, a faster degradation rate and drug release rate.Poly(p-dioxanone) have good handling property, tissue compatibility and bio-degradability. The polymer was melt extruded into pliable, monofilament fibers by Doddi N. in 1976. The monofilament fiber was characterized by high tensile and knot strength and a high degree of softness and flexibility. Poly(p-dioxanone) has high degree of crystallinity which limited it to copolymerize with other monomers to be used as controlled drug release materials. A series of polyesteramide having ether linkages in the main chain have been synthesized by ring-opening polymerization by 3-morpholinone(M) and p-dioxanone(DON) in bulk using zinc powder as catalyst. The effect of reaction conditions on the monomer convertion and copolymer molecular weitht has been investigated. The result showed that the optimal reaction temperature was 120℃, the optimal duration of reaction was 24h; the optimal ratio of m(M)/m(I) was 50:1; the optimal ratio of n(M)/n(DON) was 1:1. Under the optimal condition the polymer whoseMn was 3 733 could be obtained while the weight yield was 92%.