Poly(vinyl butyral) (PVB) is widely accepted as an adhesive for glass substrates within the automobile windows. In this work, we suggested and performed butyralization of poly(vinyl alcohol) (PVA) under supercritical carbon dioxide (sc-CO2) and investigated not only the structure and mechanical properties of the obtained PVB but also its adhesion properties under various conditions, comparing this PVA with other PVBs prepared in the solution and swollen states. The conversion ratio of butyralization under sc-CO2 was larger than that in the swollen state and lower than that in the solution state and exhibited a sufficient material performance as the adhesive for glass substrates. The Young’s modulus and tensile strength of PVB under sc-CO2 were higher than those of the other PVBs. The mechanical properties of the PVB prepared under sc-CO2 have no correlation to the modification ratios because sc-CO2 penetrated into the amorphous region of the PVA and preferentially modified its hydroxyl groups. Furthermore, the adhesive strengths of all the obtained PVBs increased, and under a high-humidity atmosphere, the adhesive strength of the PVB prepared under sc-CO2 was the largest. The humidity resistance of the PVB adhesive prepared under sc-CO2 was proven. Poly(vinyl butyral) (PVB) is accepted as an adhesive to glass substrates. The PVB was prepared through butyralization of poly(vinyl alcohol) under supercritical carbon dioxides. The Young’s modulus and tensile strength of the PVB prepared under supercritical carbon dioxides were higher than those of the PVBs in the preparation method in solution and swollen states. In addition, the PVB under supercritical carbon dioxide possessed higher adhesive strength to glass substrates even under high humid condition, compared with the other PVBs.

中文翻译：

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聚（乙烯醇）在超临界二氧化碳下的丁醛化，用于玻璃基板的耐湿粘合剂

聚乙烯醇缩丁醛 (PVB) 作为汽车车窗玻璃基材的粘合剂被广泛接受。在这项工作中，我们建议并在超临界二氧化碳 (sc-CO2) 下对聚乙烯醇 (PVA) 进行丁醛化，不仅研究了所得 PVB 的结构和机械性能，还研究了其在各种条件下的粘合性能，比较这种 PVA 与在溶液和溶胀状态下制备的其他 PVB。sc-CO2下缩丁醛化的转化率高于溶胀状态，低于溶液状态，表现出足够的材料性能作为玻璃基板的粘合剂。在sc-CO2 下PVB 的杨氏模量和拉伸强度高于其他PVB。在sc-CO2下制备的PVB的机械性能与改性率没有相关性，因为sc-CO2渗透到PVA的无定形区域并优先改性其羟基。此外，所得PVBs的粘合强度均有所增加，在高湿气氛下，sc-CO2下制备的PVB粘合强度最大。证明了在 sc-CO2 下制备的 PVB 粘合剂的耐湿性。聚乙烯醇缩丁醛 (PVB) 被认为是玻璃基材的粘合剂。PVB 是通过在超临界二氧化碳下对聚乙烯醇进行丁缩反应制备的。在超临界二氧化碳条件下制备的PVB的杨氏模量和拉伸强度均高于溶液和溶胀状态下制备方法中PVB的杨氏模量和拉伸强度。此外，