由於半芳香型聚醯胺顯著的機械性質、熱性質以及良好的尺寸穩定性，其已成為芳香型聚醯胺以及脂肪型聚醯胺的替代方案。值得注意的是，在合成聚對苯二甲醯癸二胺(PA10T)中使用的癸二胺，其來源於蓖麻油，為一種生質材料，有利於發展綠色化學以及永續發展。然而PA10T的熔點接近其裂解溫度，從而限制其加工性。利用PA10與4-Aminomethylbenzoic acid (4-AmBA)共同聚合可以解決這項缺點。在這項研究中，我們系統性的研究了PA10T與其共聚物的結晶行為以及形態學，透過操控共單體的比例以及結晶條件，研究不同條件下PA10T的結晶行為，包括結晶動力學、晶體厚度的減少、球晶的破壞、高分子的鏈堆積以及Brill transition。共單體對於PA10T結晶的影響導致PA10T的熔點降低，使加工溫度範圍變大，也讓PA10T在工業上有更高的實用性。

Semi-aromatic polyamide has emerged as a promising alternative to both aliphatic and aromatic polyamides due to its remarkable mechanical, thermal properties, along with excellent dimensional stability. Notably, the monomer 1,10-diaminodecane used in the synthesis of a semi-aromatic polyamide, poly(decamethylene terephthalamide) (PA10T), is derived from cast oil—a biobased raw material aligning with the green chemistry for sustainable development. Nevertheless, the melting point of PA10T is still near its degradation temperature, thereby limiting its processing condition and applicability. Copolymerization of PA10T with 4-Aminomethylbenzoic acid (4-AmBA) has been exploited as an approach to circumvent this potential drawback. In this study, we systematically investigate the crystallization behavior and crystalline morphology of PA10T and its copolymers with 4-AmBA, aiming to lay the groundwork for controlling the structure by manipulating comonomer composition and crystallization condition. The introduction of the comonomer into the PA10T backbone is found to impact the crystallization behavior of PA10T, including the reductions of crystallization kinetics and crystal thickness as well as the perturbations of the spherulite morphology, chain packing in the crystal lattice, and Brill transition. Notably, these perturbations resulted in a broadening of the melt processing window for PA10T. This widened processing window holds substantial practical implications, potentially expanding the applicability of PA10T in various industrial contexts.

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