以均苯四甲酰四二乙醇胺为核的水溶性超支化聚酰胺-酯的合成与表征

Synthesis and characterization of water-solubility hyperbranched polyamido-ester with pyromellit-tetra-diethanol amine as central core

超支化聚酰胺-酯(HPAE)含有类似于球形状的分子结构和大量活性端基,因而在胶粘剂、涂料、流变改性剂及染料等领域中具有潜在的应用前景。以均苯四甲酸酐(PMDA)和二乙醇胺(DEA)为原料,合成出一种中心核(By);然后以2,2-二羟甲基丙酸(DMPA)为AB2单体,将其与By进行熔融缩聚反应,制成水溶性的HPAE。结果表明:By的数均相对分子质量(Mn)、重均相对分子质量(Mw)分别为1 697、1 889 g/mol,Mw/Mn=1.11,说明其相对分子质量分布较窄;HPAE分子骨架中含有强极性酰胺键、弱极性酯键和大量强极性羟基,易溶于水;水溶性HPAE的支化度为0.47,其Mn、Mw分别为2 195、3 676 g/mol,Mw/Mn=1.67。合成原料易得、工艺简单,适合大量制备超支化聚合物。

The hyperbranched polyamido-ester（HPAE） has potential application prospect in the fields of adhesives, coating,rheology modifier and dyestuff because of its similarly spherical molecule structure and plenty of function end groups. The By（pyromellit-tetra-diethanol amine） as central core was prepared with pyromellitic dianhydride（PMDA） and diethanol amine（DEA） as raw materials,then the water-solubility HPAE was prepared by melting condensation polymerization between DMPA （2,2-dimethylolpropionic acid） as AB2 monomer and By. The results showed that the By has narrow molecular weight distribution because its polydispersity（Mw/Mn） was 1.11, Mn（number average molecular weight） and Mw（weight average molecular weight） were 1 697 g/mol and 1 889 g/mol respectively. The HPAE had well water-solubility because some function bonds （such as high polar amide bond, poor polar ester bond and a mass of high polar hydroxyl end groups） exist in HPAE molecular frame. The watersolubility HPAE had higher degree of branching（0.47） and wide molecular weight distribution because its Mn and Mw were 2 195 g/mol and 3 676 g/mol respectively,MdMn was 1.67. The hyperbranched polymer can be fordized because its synthesis process was simplicity and raw materials were easy obtained.