Purpose: Development of PVA/cellulose fiber composite material with modulable properties, obtained through the increase of reinforcement and heat treatments in order to optimize the composite in terms of mechanical, thermal, and degradation properties. Methods: The composite was designed selecting as matrix an experimental formulation based on water-soluble, biodegradable, polyvinyl alcohol (PVA) and microcrystalline cellulose (MCC), as reinforcement. Six different formulations, with increasing ratio of MCC content (from 0% to 55% w/w) in PVA, were developed and extruded by a co-rotating twin-screw extruder (TSA FSCM 21/40). Then, samples have been treated through two different thermal conditions (T1, T2) and characterized by scanning electron microscopy, tensile mechanical tests, thermogravimetric analysis, and water degradation tests to investigate, respectively, the influence of MCC ratios and heat treatment on morphological, mechanical, degradation, and thermal properties. Results: The PVA/MCC composite exhibited a good stress–strain behavior as well as a close correlation between MCC content on tensile, thermal, and degradation properties. The second part of the results includes the analysis of the effects that the thermal treatments (T1, T2) had on the composite. In fact, thermal treatments have allowed improving the thermal and water stability as well as a significant improvement in the considered mechanical parameters due to a possible crosslinking of the PVA matrix. Conclusion: The present work shows how the properties of the PVA/MCC composite can become modular with the aim of extending its range of application as a new sustainable solution in the field of consumer products.

中文翻译：

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PVA/纤维素纤维复合材料的可调制性能

目的：开发具有可调节性能的 PVA/纤维素纤维复合材料，通过增加增强和热处理获得，以优化复合材料的机械、热和降解性能。方法：选择基于水溶性、可生物降解的聚乙烯醇 (PVA) 和微晶纤维素 (MCC) 作为增强材料的实验配方作为基质设计复合材料。开发了六种不同的配方，其中 PVA 中的 MCC 含量比例增加（从 0% 到 55% w/w），并通过同向双螺杆挤出机 (TSA FSCM 21/40) 挤出。然后，样品通过两种不同的热条件（T1、T2）进行处理，并通过扫描电子显微镜、拉伸力学测试、热重分析、和水降解试验，分别研究 MCC 比率和热处理对形态、机械、降解和热性能的影响。结果：PVA/MCC 复合材料表现出良好的应力-应变行为，以及 MCC 含量与拉伸、热和降解性能之间的密切相关性。结果的第二部分包括对热处理（T1、T2）对复合材料的影响的分析。事实上，由于 PVA 基体可能发生交联，热处理可以改善热稳定性和水稳定性，并显着改善所考虑的机械参数。结论：