In this study, biodegradable polylactic acid (PLA)/chitosan (Cs) composites were produced via melt compounding and compression molding techniques. Various chitosan loadings of 2.5, 5, 7.5 and 10 parts per hundred parts of polymer (php) were incorporated into PLA and its effects on thermal, water absorption kinetics, tensile and morphological characteristics were investigated systematically. Thermal analysis indicated that an increase in chitosan loading of up to 10 php enhanced the crystallinity percentage (χ_c) of neat PLA to an extent of 51%, yet reduced the thermal stability of the resulting biocomposites. The kinetic study results revealed that water absorption of PLA/Cs biocomposites approached the Fickian diffusion behavior. The maximum water uptake (M_sat) increased with chitosan addition, which can be attributed to stronger water–filler interaction. This was correlated to higher diffusion (D), solubility (S) and permeability (P) coefficients, which suggested the acceleration in diffusion rate and better water permeation through the biocomposites. In addition, the tensile results of dry samples showed enhancement in tensile strength and tensile modulus by 2% and 14%, respectively, relative to neat PLA through the incorporation of 2.5 php of chitosan loading. However, the water-immersed biocomposites demonstrated deterioration in all tensile properties (tensile strength, tensile modulus, and elongation-at-break values) which signified hydrolytic polymer degradation. This was confirmed by the FESEM micrographs of the fractured surfaces which exhibited filler pulled-out phenomenon and cavity formation after 50 days of water immersion.

在这项研究中，可生物降解的聚乳酸（PLA）/壳聚糖（Cs）复合材料是通过熔融复合和压缩成型技术生产的。每100份聚合物（php）中加入2.5、5、7.5和10份各种壳聚糖的量，并系统地研究了其对热，吸水动力学，拉伸和形态特征的影响。热分析表明〜10的PHP增加了的脱乙酰壳多糖装载增强结晶度百分比（χ _Ç）整齐PLA至51％的程度，但降低了所得到的生物复合材料的热稳定性。动力学研究结果表明，PLA / Cs生物复合材料的吸水率接近Fickian扩散行为。最大吸水量（M _sat）随着壳聚糖的添加而增加，这可以归因于较强的水与填料的相互作用。这与较高的扩散度（D），溶解度（S）和渗透率（P）系数，这表明扩散速率加快，并且通过生物复合材料的水渗透性更好。另外，相对于纯净的PLA，通过掺入2.5 php的壳聚糖负载，干样品的拉伸结果显示其拉伸强度和拉伸模量分别提高了2％和14％。但是，水浸式生物复合材料在所有拉伸性能（拉伸强度，拉伸模量和断裂伸长率值）方面均表现出劣化，这表明水解聚合物降解。断面的FESEM显微照片证实了这一点，该断面在浸水50天后表现出填料拔出现象和空洞形成。