A novel triamine (1) with tert-butyl side group, N1,N1-bis(4-aminophenyl)-4-(tert-butyl)benzene-1,3-diamine, is synthesized and then polymerized with the dianhydride 6FDA (A₂) at the different feed molar ratio. Monitoring by ¹H NMR spectrum, the reactivity of 3-amino group with ortho-tert-butyl is much lower than that of 4′/4″-amino groups in triamine 1. Thus AB₂-type amic acid (B’A₂ intermediates) can be formed rapidly in situ when the polymerization is processed at 20 °C and the molar ratio of 1/6FDA is 1:2. Subsequently with increasing the polymerization temperature, 3-amino group with ortho-tert-butyl in AB₂-type intermediates is activated and self-polycondensed with anhydride groups to produce hyperbranched polyimide (HBPI) without gelation. This indicates that it’s an effective approach to decrease the reactivity of amino groups in triamine by introducing tert-butyl into its ortho-position and HBPIs can be prepared conveniently through the method of ‘A₂+B’B₂′ based on the principle of unequal reactivity of functional groups.

合成了具有叔丁基侧基的新型三胺（1）N1，N1-双（4-氨基苯基）-4-（叔丁基）苯-1,3-二胺，然后与二酐6FDA（A ₂）在不同的进料摩尔比下。通过监测^1个H NMR谱，3-氨基团与反应活性邻-叔丁基比4'/ 4“ -氨基中的三胺基团的要低得多1。因此，当在20°C和1 /摩尔比的条件下进行聚合反应时，可以迅速就地形成AB ₂型酰胺酸（B'A ₂中间体）。6FDA是1：2。随后与提高聚合温度，3-氨基与邻-叔丁基在AB ₂型的中间体被活化并与酸酐基团的自缩聚而不会凝胶化，以产生支化聚酰亚胺（HBPI）。这表明，它是一个有效的方法通过引入降低氨基团的反应性在三胺叔丁基到其邻位和HBPIs可以通过的方法“A方便地制备₂ + B'B ₂基于的原则'官能团的反应性不平等。