The effects of water molecules on the chemical structure, microstructure, molecular kinematics, and relaxation behavior of polyvinyl butyral (PVB) films were investigated. The 2D ATR-FTIR results demonstrated that water molecules initially interacted with free O–H and C═O, subsequently with hydrogen-bonded O–H and C═O between the hard and soft segments, and ultimately with hydrogen-bonded O–H and C═O in the hard segments. The SEM, AFM, DSC, and SAXS-WAXS results indicated that the microphase separation structure of PVB was formed by soft and hard domains, and the entry of water molecules disrupted the original structural regularity of the hard segments of the PVB films, resulting in a decrease in microphase separation degree. The BDRS results showed that water absorption had a significant effect on the molecular kinematics of the soft segments and the hard–soft interface. The results of the stress relaxation behavior showed that the relaxation properties of PVB films deteriorated after water absorption.

中文翻译：

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了解吸水率对聚乙烯醇缩丁醛薄膜的微观结构、分子运动学和松弛行为的影响


研究了水分子对聚乙烯醇缩丁醛 （PVB） 薄膜化学结构、微观结构、分子运动学和松弛行为的影响。2D ATR-FTIR 结果表明，水分子最初与游离 O-H 和 C═O 相互作用，随后在硬链段和软链段之间与氢键 O-H 和 C═O 相互作用，最终在硬链段与氢键 O-H 和 C═O 相互作用。SEM、AFM、DSC 和 SAXS-WAXS 结果表明，PVB 的微相分离结构是由软结构域和硬结构域形成的，水分子的进入破坏了 PVB 薄膜硬结构段的原始结构规则，导致微相分离度降低。BDRS 结果表明，吸水率对软链段和硬-软界面的分子运动学有显著影响。应力松弛行为的结果表明，PVB 薄膜在吸水后松弛性能变差。