Department of Chemistry "Ugo Schiff" and CSGI, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Florence, Italy.
Department of Chemistry "Ugo Schiff" and CSGI, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Florence, Italy.
J Colloid Interface Sci. 2023 Jan 15;630(Pt B):415-425. doi: 10.1016/j.jcis.2022.10.092. Epub 2022 Oct 21.
The role of amylose and amylopectin in the formation of cryogels based on Poly(vinyl alcohol) (PVA) and starch is poorly understood. A systematic investigation of simplified systems containing PVA, amylose, and/or amylopectin constitutes the basis to predict the final features of PVA/starch cryogels by knowing their composition, and the amylose content of the employed raw starches.
Pre-gel solutions and cryogels containing PVA/amylose, PVA/amylopectin, and PVA/amylose/amylopectin in variable ratios were investigated employing small-angle X-ray scattering (SAXS), confocal laser scanning microscopy (CLSM), differential scanning calorimetry (DSC), and rheological measurements. The gel fraction (G%) of 23 samples with variable compositions was calculated and plotted to predict the G% (the gel fraction) of any PVA/amylose/amylopectin mixing ratio.
We report on how the PVA, amylose, and amylopectin composition affect the properties of the final polymer blend and cryogel formation. In particular, PVA/amylose and PVA/amylopectin show different behaviors with respect to cryogel formation. We show that is possible to predict cryogel formation by using the simple G% parameter for any PVA/amylose/amylopectin mixing ratio, ruling out the starch botanical origin in the gel formation. The results reported in this work represent a simple tool, able to predict the formation of high-quality biobased materials that can replace fully synthetic materials with a significantly positive impact on our ecosystem.
基于聚乙烯醇（PVA）和淀粉形成的低温水凝胶中，直链淀粉和支链淀粉的作用知之甚少。通过了解其组成以及所使用原料淀粉的直链淀粉含量，对含有 PVA、直链淀粉和/或支链淀粉的简化系统进行系统研究，是预测 PVA/淀粉低温水凝胶最终特性的基础。
采用小角 X 射线散射（SAXS）、共聚焦激光扫描显微镜（CLSM）、差示扫描量热法（DSC）和流变学测量等方法，研究了含有 PVA/直链淀粉、PVA/支链淀粉和 PVA/直链淀粉/支链淀粉的预凝胶溶液和低温水凝胶，其中各成分的比例可变。对 23 种具有不同组成的样品的凝胶分数（G%）进行了计算和绘图，以预测任何 PVA/直链淀粉/支链淀粉混合比的 G%（凝胶分数）。
我们报告了 PVA、直链淀粉和支链淀粉的组成如何影响最终聚合物共混物和低温水凝胶形成的性质。特别是 PVA/直链淀粉和 PVA/支链淀粉在低温水凝胶形成方面表现出不同的行为。我们表明，通过使用简单的 G%参数，可以预测任何 PVA/直链淀粉/支链淀粉混合比的低温水凝胶形成，排除了淀粉植物学起源对凝胶形成的影响。本工作所报道的结果代表了一种简单的工具，能够预测高质量生物基材料的形成，这些材料可以替代完全合成的材料，对我们的生态系统产生重大的积极影响。
