生物基聚酰胺56低聚物改性聚酯的合成及其表征

Synthesis and characterization of bio-based polyamide 56 oligomer modified polyester

为改善聚酯(PET)的亲水性,采用生物基聚酰胺56低聚物(LPA56)对聚酯进行共聚改性制备新型聚酰胺酯共聚物。借助核磁共振波谱仪、傅里叶红外光谱仪、X射线衍射仪和光学接触角测量仪等对新型聚酰胺酯的结构和性能进行表征与分析。结果表明:新型聚酰胺酯共聚物兼具酯类和酰胺类特征官能团振动峰,且LPA56的反应率达到80%以上;共聚物的晶型和聚酯晶型相同,但其结晶度随着LPA56质量分数的增加而逐渐降低;随着LPA56质量分数的增加,共聚物的玻璃化转变温度、熔点逐渐降低,但其对共聚物热稳定性影响较小;当加入质量分数为5%的LPA56时,共聚物的静态接触角从91.5°降低至70.3°;改性后PET纤维的回潮率是改性前的265%,并随着LPA56质量分数的增加而逐渐提高。

In view of the poor hydrophilicity of polyester (PET), a novel polyamide ester copolymer was prepared by copolymerization modification of PET with bio-based polyamide 56 oligomer (LPA56). Structure and properties of the novel polyamide esters were characterized and analyzed by nuclear magnetic resonance spectrometer, Fourier transform infrared spectroscopy, X-ray diffractometer and optical contact angle measuring instrument. The results show that the novel polyamide esters have functional peaks of both esters and amides, and the reaction rate of LPA56 is over 80%. The copolymers and polyesters have the same crystal form. However, the crystallinity decreases with the increase of the amount of LPA56 added. The glass transition temperature and melting point of the copolymer gradually decrease with the increase of the amount of LPA56 added, but the thermal stability of the copolymer is less affected. When 5% LPA56 is added, the static contact angle is greatly reduced from 91.5° to 70.3°, and the fiber moisture regain is 265% of the pre-modified PET fiber, and gradually increases with the amount of LPA56 added.