Naffakh Mohammed, Shuttleworth Peter S
Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain.
Instituto de Ciencia y Tecnología de Polímeros (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain.
Polymers (Basel). 2022 Jun 30;14(13):2692. doi: 10.3390/polym14132692.
The aim of this work was to study the crystallization kinetics and melting behaviour of polymer blend nanocomposites based on poly (L-lactic acid) (PLLA), nylon 11 and tungsten disulfide nanotubes (INT-WS), which are layered transition metal dichalcogenides (TMDCs), using non-isothermal differential scanning calorimetry (DSC). Blends containing different nylon 11 contents ranging from 20 to 80 wt.% with or without INT-WS were prepared by melt mixing. Evaluation of their morphology with high-resolution SEM imaging proved that the incorporation of inorganic nanotubes into the immiscible PLLA/nylon 11 mixtures led to an improvement in the dispersibility of the nylon 11 phase, a reduction in its average domain size and, consequently, an increase in its interfacial area. The crystallization temperatures of these PLLA/nylon 11-INT blends were influenced by the cooling rate and composition. In particular, the DSC results appear to demonstrate that the 1D-TMDCs WS within the PLLA/nylon 11-INT blend nanocomposites initiated nucleation in both polymeric components, with the effect being more pronounced for PLLA. Moreover, the nucleation activity and activation energy were calculated to support these findings. The nucleation effect of INT-WS, which influences the melting behaviour of PLLA, is highly important, particularly when evaluating polymer crystallinity. This study opens up new perspectives for the development of advanced PLA-based nanomaterials that show great potential for ecological and biomedical applications.
本工作的目的是使用非等温差示扫描量热法（DSC）研究基于聚（L-乳酸）（PLLA）、尼龙11和二硫化钨纳米管（INT-WS）的聚合物共混物纳米复合材料的结晶动力学和熔融行为，二硫化钨纳米管是层状过渡金属二硫属化物（TMDCs）。通过熔融共混制备了含有20至80 wt.%不同尼龙11含量且有或无INT-WS的共混物。用高分辨率扫描电子显微镜成像对其形态进行评估，结果表明，将无机纳米管加入到不相容的PLLA/尼龙11混合物中，可改善尼龙11相的分散性，减小其平均畴尺寸，从而增加其界面面积。这些PLLA/尼龙11-INT共混物的结晶温度受冷却速率和组成的影响。特别是，DSC结果似乎表明，PLLA/尼龙11-INT共混物纳米复合材料中的一维TMDCs WS在两种聚合物组分中均引发成核，对PLLA的影响更为显著。此外，还计算了成核活性和活化能以支持这些发现。INT-WS的成核作用会影响PLLA的熔融行为，这一点非常重要，尤其是在评估聚合物结晶度时。本研究为开发先进的基于聚乳酸的纳米材料开辟了新的前景，这类材料在生态和生物医学应用方面具有巨大潜力。
