The present paper describes the novel aliphatic polyamide 6 (PA6) copolyamides by the melt polymerization reaction of our newly synthesized aliphatic diamine monomer: N 1 , N 6 -Bis-(2-aminoethyl)adipamide (BAEA). The BAEA/CHDA (1,4-cyclohexanedicarboxylic acid) salt was prepared by pertinent long-chain polyamide with the cycloaliphatic ring and isolated as white solid, utterly characterized for the first time. The chemical structure of BAEA, BAEA/CHDA salt and copolyamides (PA6-BAEA/CHDA) was identified by 1 H NMR and FT-IR spectroscopy. Depending on the chemical compositions, the viscosity and molecular weight of the copolyamides were in the range of 19,447–13,536 g mol −1 and 2.74–2.2 dL g −1 . With increasing BAEA/CHDA salt molar ratio in the synthesized copolyamides, their melting temperatures ( T m ) decreased from 212.7 to 170.4 °C, and the glass transition temperatures ( T g ) increased from 60 to 89.4 °C. Besides, the as-synthesized all copolyamides possess nearly similar thermal stability ( T d-50% = 439.59 − 443.38 °C) as neat PA6. Mechanical testing data revealed that with an increase in a proportion of BAEA/CHDA salt, Young’s modulus of copolyamides is increased from 698.54 to 1093.89 MPa, while the tensile strength is increased by 8.1%.

中文翻译：

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1,4-环己烷二甲酸对共聚酰胺热力学性能的影响

本论文通过我们新合成的脂肪族二胺单体 N 1 , N 6 -双-(2-氨基乙基)己二酰胺 (BAEA) 的熔融聚合反应描述了新型脂肪族聚酰胺 6 (PA6) 共聚酰胺。BAEA/CHDA（1,4-环己烷二甲酸）盐是由相关的长链聚酰胺与脂环族环制备的，分离为白色固体，首次完全表征。BAEA、BAEA/CHDA 盐和共聚酰胺 (PA6-BAEA/CHDA) 的化学结构通过 1 H NMR 和 FT-IR 光谱确定。根据化学成分的不同，共聚酰胺的粘度和分子量在 19,447-13,536 g mol -1 和 2.74-2.2 dL g -1 的范围内。随着合成共聚酰胺中 BAEA/CHDA 盐摩尔比的增加，它们的熔化温度 (Tm) 从 212.7 降低到 170.4°C，并且玻璃化转变温度 (T g ) 从 60 增加到 89.4 °C。此外，合成的所有共聚酰胺具有与纯 PA6 几乎相似的热稳定性 (T d-50% = 439.59 − 443.38 °C)。力学测试数据表明，随着BAEA/CHDA盐比例的增加，共聚酰胺的杨氏模量从698.54 MPa提高到1093.89 MPa，而拉伸强度提高了8.1%。