Abstract: The hydroxyl terminated hyperbranched polyester(HBPE) was synthesized based on 2, 2-dimethylol propionic acid (DMPA via a melt polycondensation. The peripheral hydroxyls of HBPE were transformed to terminal ester groups through esterification with acetic acid, to improve the solubility of HB-PE. By use of silane coupling agent KH550 the modified HBPE (MHBPE) was grafted onto the of e surtace ultrafine titanium dioxide by amidation reaction. The modified ultrafine titanium dioxide was characterized by FT-IR, elemental analysis and TG. The results indicated that MHBPE was successfully grafted onto the surface of ultrafine titanium dioxide. The results of semination experiment and Uv-vis analysis showed that the ultrafine titanium dioxide grafted with MHBPE gave a stable dispersion in ethyl acetate and tetra-hydrofuran solvents.

Key words: hyperbranched polyester, terminal group modification, ultrafine titanium dioxide, surface modification, dispersion stability

摘要： 以 2，2-二羟甲基丙酸(DMPA)为原料，采用熔融缩聚反应合成了端羟基超支化聚酯(HBPE);通过与乙 酸的酯化反应，将 HBPE分子外围的羟基转化为酯基，明显改善了 HBPE的溶解性能。以硅烷偶联剂 KH50为桥梁， 利用酰胺化反应将改性的 HBPE(记做 MHBPE)接枝到超细二氧化钛表面。红外光谱、元素分析和 TG测试结果证明 MHBPE成功接枝到超细二氧化钛表面。沉降实验和紫外可见光分析结果表明，接枝了 MHBPE的超细二氧化钛在乙 酸乙酯和四氢呋喃溶剂中有很好的分散稳定性。

关键词: 超支化聚酯 , 端基改性 , 超细二氧化钛 , 表面改性 , 分散稳定性