乳酸基聚氨酯与羟基磷灰石的共价杂化

摘要

由乳酸聚乙二醇酯二醇中间体(LPEG)、羟基磷灰石以及甲苯-2,4-二异氰酸酯(TDI)发生加聚反应,探讨羟基磷灰石与乳酸基聚氨酯的共价杂化.对提纯后的杂化产物(HA-g-LPEU5K)及相应共混体系(HA/LPEU5K)的结构及其热稳定性进行了分析对比,HA-g-LPEU5K和HA/LPEU5K热解的剩余百分数分别为92.5％和41.7％.共价和物理杂化物静置3d后,分别呈均相、出现少量HA沉淀.杂化体系的稳定性明显高于共混物,说明乳酸基聚氨酯与羟基磷灰石通过共价键结合而实现了共价杂化.此外,杂化体系呈现可降解性.%The addition reaction of a lactic acid-based diol intermediate(LPEG),hydroxyapatite with toluene2,4-diisocyanate (TDI) was employed to form the covalent hybrid of hydroxyapatite and lactic acid-based polyurethane.The structure and thermal stability of the hybrid were analyzed and compared with the corresponding blends.Thermogravimetric analysis shows that the remained fractions of HA-g-LPEU5K and HA/LPEU5K are 92.5％ and 41.7％,respectively.The hydrids are still homogeneous while precipitation is found in the blend solutions after settling at temperature for three days.The stability of the hybrid is significantly higher than that of the blends,which confirms that the covalent hybrid of lactic acid-based polyurethane and hydroxyapatite is successfully obtained.In addition,the hybrid systems exhibit degradable properties.