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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。
Hyperbranched polyamide-ester (HPAE) contains spherical molecular structure and a large number of active end groups, so it has potential applications in the fields of adhesives, coatings, rheology modifiers and dyes. A kind of central nucleus (By) was synthesized from pyromellitic dianhydride (PMDA) and diethanolamine (DEA). Then 2,2-dimethylol propionic acid (DMPA) And By melt polycondensation reaction, made of water-soluble HPAE. The results showed that the number average molecular weight (Mn) of By and the weight average molecular weight (Mw) were 1 697 and 1 889 g / mol, respectively, and Mw / Mn was 1.11, which indicated that the relative molecular mass distribution was narrow. The backbone contains strongly polar amide bonds, weakly polar ester bonds and a large number of strongly polar hydroxyl groups, which are easily soluble in water. The degree of branching of water-soluble HPAE is 0.47, and its Mn and Mw are respectively 2 195 and 3676 g / mol , Mw / Mn = 1.67. Synthetic raw materials easily available, process is simple, suitable for large quantities of hyperbranched polymers.