Non-isothermal crystallization kinetics of polyvinyl alcohol plasticized with glycerol and pentaerythritol

Abstract

In this work, we chose different ratios of glycerol and pentaerythritol to plasticize PVA. The solid and liquid were compounded to plasticize PVA, because pentaerythritol had a large molecular weight and a high boiling point, which can sovle the gycerol’s migration problem and make it beneficial for long-term plasticization. The interaction of the hydroxyl group of a large molecular weight plasticizer with the PVA hydroxyl group has not been observed for the influence of the PVA molecular chain into the crystal lattice. So, this work investigated the crystallization behaviors in detail. The results showed that the addition of plasticizer can change the regular structure of PVA. It made it difficult to discharge the molecular chain into the crystal lattice and hindered the crystallization of PVA. After the addition of plasticizer, the crystallization energy required increased. The XRD indicates that the plasticizers of different molecular weights can effectively destroy the original crystal structure of PVA, and the plasticizer interacted with PVA to form stronger hydrogen bonds to replace the intermolecular phase of PVA itselfs intramolecular interactions.