【作者】 孙帅；

【导师】 朱蔚璞； 沈之荃；

【作者基本信息】 浙江大学 ， 高分子化学与物理， 2012， 硕士

【摘要】 价格低廉的聚己内酯(PCL)有着良好的生物相容性、可加工性、药物透过性,在生物医用材料中已经被应用到组织工程,药物控释等多个领域。但是其结晶度高和疏水性使得其生物降解速率很慢,阻碍了其在生物医用材料中进一步的应用。磷酸酯聚合物同样有着良好的生物相容性,在生物医用材料中也是研究热门。己内酯和磷酯的共聚产物可以很好的结合两者的优点,得到有生物相容性好、价格低廉和生物降解性好的材料。同时,磷原子的五价结构使共聚物很容易进行化学修饰,这样的可降解材料在生物医用材料有着潜在的应用前景。本论文采用芳氧基稀土化合物在温和条件下催化己内酯和环磷酸酯的开环共聚合,合成了己内酯磷酸酯无规共聚物。选取了氯乙氧基环磷酸酯和炔丙氧基环磷酸酯作为共聚单体,得到含卤素或炔基的官能化共聚物,分别通过直接季铵化反应和“点击”化学反应,将季铵盐基团引入到共聚物中。共聚物的组成、结构和分子量通过核磁共振(NMR)、红外光谱(IR)、凝胶渗透色谱(GPC)等手段表征,还通过X射线衍射(XRD)、差示扫描量热法(DSC)、静态接触角等表征了无规共聚物及其季铵化产物的结晶度、熔点及亲水性。采用扫描电子显微镜(SEM)、OD600法和抑菌圈法表征了具有不同磷脂含量和烷基链长的季铵化聚合物的抗菌性能,含有十二烷基疏水链的季铵化产物具有较好的抗菌性能,这种可降解抗菌聚合物有望在生物医用材料领域得到应用。更多还原

【Abstract】 Polycaprolactone(PCL) has attracted considerable interest in biomedicine, pharmacy, and tissue engineering because of its good drug permeability, biocompatibility, nontoxicity, and low cost. However, hydrolytic degradation rate of PCL is rather low because of its high crystallinity and hydrophobicity, and the lack of functional groups on PCL chain prevents it from further modification, which restrains its potential applications. Polyp hosphoesters are another kind of biomedical material with good biodegradability and hydrophilicity, which has attracted interesting all over the world. The copolymer of ε-caprolcatone and phosphoester has higher hydrophilicity and faster degradation rate than PCL homopolymer. In addition, the copolymers could be facilely modified on the phosphoester unit due to the pentavalent phosphorus atom. This work reports the synthesis and characterization of copolymer based on cyclic phosphoesters and ε-caprolcatone via rare earth phenolates catalysted ring-opening copolymerization under mild conditions. Utilizing2-(2-chloroethoxy)-2-oxo-1,3,2-di-oxaphospholane and2-(2-propynyloxy)-2-oxo-1,3,2-dioxaphospholane as functional cyclic phosphoester comonomer, poly(ester-phosphoester)s bearing chloro and alkyne functional groups were prepared respectively. Ammonium groups were introduced into these copolymers by direct quaternization or "click" chemistry, resulting in biodegradable poly(ester-phosphoester)s with antibacterial properties. The composition and chain structure of copolymer were characterized by NMR, FT-IR and GPC. The crystallinity and hydrophilicity of the copolymers were studied by XRD, DSC, SWCA in detail. The antibacterial abilities of the copolymers with ammonium groups were characterized by SEM, OD600and inhibition zone methods. The copolymers with dodecyl groups on the ammonium moieties exhibit higher antibacterial ability than those with shorter alkyl chains.更多还原