Abstract Solvent-free and highly branched water-soluble polyester (WPET) is prepared through self-emulsification methodology, using dimethyl terephthalate (DMT), sodium dimethyl isophthalate-5-sulfonate (SIPM), trimethylolpropane (TMP), and ethylene glycol (EG) by the transesterification and polycondensation. The WPET were first utilized as surface-sizing agents for cellulose fiber paper. The structure, average molecular weights, and physical properties of the water-soluble polyester were characterized by FTIR, 1H NMR, gel permeation chromatography (GPC), dynamic light scattering (DLS), X-ray diffraction (XRD), and dynamic rheometer. The effects of polymer structure and properties, as well as the surface sizing of the paper, were investigated. WPET displayed better surface sizing properties when it was prepared under the following conditions: –COO/–OH molar ratio of 1:2, the SIPM content of 17.98%, and TMP content of 11.10%. The relationships between the WPET structure and sized paper were clearly illustrated. The mechanical properties and water resistance of sized paper did not only depend on multi-branched hydroxyl groups of the WPET chains but also relied on the interactions among polymers and fibers, as well as the high toughness of surface sizing agent. The sizing paper possesses excellent mechanical properties as well as water resistance.

中文翻译：

---

高支化水溶性聚酯的合成及其表面施胶剂增强机理

摘要 以对苯二甲酸二甲酯 (DMT)、间苯二甲酸二甲酯-5-磺酸钠 (SIPM)、三羟甲基丙烷 (TMP) 和乙二醇 (EG) 为原料，通过自乳化方法制备了无溶剂、高度支化的水溶性聚酯 (WPET)。 ) 通过酯交换和缩聚。WPET首先被用作纤维素纤维纸的表面施胶剂。通过FTIR、1H NMR、凝胶渗透色谱(GPC)、动态光散射(DLS)、X射线衍射(XRD)和动态流变仪对水溶性聚酯的结构、平均分子量和物理性质进行了表征。研究了聚合物结构和性能以及纸张表面施胶的影响。WPET 在以下条件下制备时显示出更好的表面施胶性能：–COO/–OH 摩尔比为 1:2，SIPM 含量为 17.98%，TMP 含量为 11.10%。WPET结构和施胶纸之间的关系被清楚地说明。施胶纸的机械性能和耐水性不仅取决于WPET链的多支化羟基，还取决于聚合物与纤维之间的相互作用，以及表面施胶剂的高韧性。施胶纸具有优良的机械性能和耐水性。施胶纸的机械性能和耐水性不仅取决于WPET链的多支化羟基，还取决于聚合物与纤维之间的相互作用，以及表面施胶剂的高韧性。施胶纸具有优良的机械性能和耐水性。施胶纸的机械性能和耐水性不仅取决于WPET链的多支化羟基，还取决于聚合物与纤维之间的相互作用，以及表面施胶剂的高韧性。施胶纸具有优良的机械性能和耐水性。