The use of renewable materials with unique properties has brought new perspectives regarding their use as potential substitutes to the petroleum-based products. The aim of this work was to evaluate the effects caused by the addition of Kraft lignins, selectively precipitated in acid and alkaline medium, on the thermal, thermo-oxidative, UV-blocking, antioxidant, antimicrobial and mechanical properties of polyvinyl alcohol (PVA) films. Kraft lignins (KL) were selectively precipitated in alkaline (KL A) and acid (KL B) media. KL A and KL B were characterized by FTIR, ¹H-¹³C HSQC, ³¹P NMR and GPC. PVA films were produced through casting method and characterized by TGA, DSC, OOT, UV–Vis, mechanical, antioxidant and antimicrobial properties. The selective precipitation process yielded lignins with different concentration of phenolic and total hydroxyls for KL A and KL B. The addition of KL A and KL B at 1.0% wt. in PVA films produced materials with enhanced thermal, thermo-oxidative, UV-blocking, mechanical, antioxidant and antimicrobial properties. It can be concluded that the selective precipitation of lignin represents an alternative for obtaining fractions with peculiar structural features that can improve their compatibility with thermoplastics, yielding potential bio-based products with suitable features to be used as packaging materials.

使用具有独特性能的可再生材料为将其用作石油基产品的潜在替代品带来了新的视角。这项工作的目的是评估添加硫酸盐木质素（在酸性和碱性介质中选择性沉淀）对聚乙烯醇 (PVA) 的热、热氧化、紫外线阻断、抗氧化、抗菌和机械性能的影响电影。硫酸盐木质素 (KL) 在碱性 (KL A) 和酸性 (KL B) 介质中选择性沉淀。KL A 和 KL B 由 FTIR 表征，¹ H- ¹³ C HSQC，³¹P NMR和GPC。PVA 薄膜通过流延法生产，并通过 TGA、DSC、OOT、UV-Vis、机械、抗氧化和抗菌性能进行表征。选择性沉淀过程为 KL A 和 KL B 产生具有不同酚类浓度和总羟基的木质素。添加 1.0% wt 的 KL A 和 KL B。在 PVA 薄膜中生产的材料具有增强的热、热氧化、紫外线阻挡、机械、抗氧化和抗菌性能。可以得出结论，木质素的选择性沉淀代表了获得具有特殊结构特征的馏分的替代方案，可以提高它们与热塑性塑料的相容性，产生具有合适特征的潜在生物基产品，用作包装材料。