Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy; Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
Chemosphere. 2024 May;356:141950. doi: 10.1016/j.chemosphere.2024.141950. Epub 2024 Apr 8.
Due to their excellent properties, polyhydroxyalkanoates are gaining increasing recognition in the biodegradable polymer market. These biogenic polyesters are characterized by high biodegradability in multiple environments, overcoming the limitation of composting plants only and their versatility in production. The most consolidated techniques in the literature or the reference legislation for the physical, chemical and mechanical characterisation of the final product are reported since its usability on the market is still linked to its quality, including the biodegradability certificate. This versatility makes polyhydroxyalkanoates a promising prospect with the potential to replace fossil-based thermoplastics sustainably. This review analyses and compares the physical, chemical and mechanical properties of poly-β-hydroxybutyrate and poly-β-hydroxybutyrate-co-β-hydroxyvalerate, indicating their current limitations and strengths. In particular, the copolymer is characterised by better performance in terms of crystallinity, hardness and workability. However, the knowledge in this area is still in its infancy, and the selling prices are too high (9-18 $ kg). An analysis of the main extraction techniques, established and in development, is also included. Solvent extraction is currently the most widely used method due to its efficiency and final product quality. In this context, the extraction phase of the biopolymer production process remains a major challenge due to its high costs and the need to use non-halogenated toxic solvents to improve the production of good-quality bioplastics. The review also discusses all fundamental parameters for optimising the process, such as solubility and temperature.
由于其优异的性能，聚羟基脂肪酸酯在可生物降解聚合物市场中越来越受到关注。这些生物基聚酯的特点是在多种环境中具有高生物降解性，克服了仅在堆肥厂使用的局限性，以及在生产中的多功能性。本文报告了文献中最成熟的技术或参考法规，用于最终产品的物理、化学和机械特性的表征，因为其在市场上的可用性仍然与其质量相关，包括生物降解证书。这种多功能性使聚羟基脂肪酸酯成为一种有前途的前景，具有可持续替代基于化石的热塑性塑料的潜力。本文分析和比较了聚β-羟基丁酸酯和聚β-羟基丁酸酯-共-β-羟基戊酸酯的物理、化学和机械性能，指出了它们目前的局限性和优势。特别是共聚物在结晶度、硬度和可加工性方面表现出更好的性能。然而，该领域的知识仍处于起步阶段，销售价格过高（9-18 美元/千克）。还包括对主要提取技术的分析，包括已建立和正在开发的技术。由于其效率和最终产品质量，溶剂萃取目前是最广泛使用的方法。在这种情况下，由于其高成本和需要使用非卤化有毒溶剂来提高高质量生物塑料的生产，生物聚合物生产过程的萃取阶段仍然是一个主要挑战。本文还讨论了优化该过程的所有基本参数，如溶解度和温度。
