Abstract: Three types of star-shaped polyethylene glycols (two arms, three arms and six arms )were synthesized by using ethylene glycol, glycerol and sorbitol as initiators.Three types of hydrophobically-modified ethoxylated urethane associative thickeners (HEUR)with star structure were synthesized by the reaction of synthesized star-shaped polyethylene glycol and octadecylisothiocyanate. The structure of HEUR was characterized by FI-IR, NMR,TEM and particle size analysis. The critical micelle concentration (CMC)and micelle aggregation numbers(N) of HEUR were determined by steady state fluorescence probe method. The effect of three types of HEUR on water thickening under different shearing rates was explored.The results showed that the HEUR with star structure were synthesized successfully. Three types of HEURs had the same CMC value and they were inclined to form bigger micelles with more arms. It was also found that HEUR with a six-arm structure provided few thickening effect on water and emulsion because the lipophilic end groups of HEUR were inclined to be self-asso-ciated, which was not conducive to formation of the network structure and increase of viscosity.

Key words: star-shaped, hydrophobically ethoxylated urethane associative

摘要： 分别以乙二醇、甘油、山梨醇作为起始剂，合成星型聚乙二醇（２ 臂、３ 臂和 ６ 臂），再将其分别与十八烷基异氰酸酯反应，得到星型结构的聚氨酯缔合型增稠剂（ＨＥＵＲ）。 采用红外、核磁、透射电镜和粒径仪等测试手段对增稠剂的结构进行表征。 采用稳态荧光探针法测定 ＨＥＵＲ 的临界胶束浓度（ＣＭＣ）和胶束聚集数（Ｎ）。 通过流变学探究并对比 ＨＥＵＲ 在不同转速下对水增稠的影响。 结果表明：成功合成了多臂星型结构的 ＨＥＵＲ；不同臂数的 ＨＥＵＲ 具有相同的 ＣＭＣ 值，且随臂数增加其形成的胶束变大；实验发现 ６ 臂 ＨＥＵＲ 对纯水以及乳液都未表现出有效的增稠作用，可能是因为 ６ 臂ＨＥＵＲ 的亲油端基出现了强烈的分子内端基缔合，使其不能与体系形成有效缔合网络以增加体系黏度。

关键词: 星型, 聚氨酯缔合型增稠剂, 临界胶束浓度, 胶束聚集数, 黏度