This study details the design and characterization of a new, biodegradable, and renewable whey/cellulose-based hydrogel (i.e., agricultural hydrogel). This was formulated from cellulose derivatives (carboxymethylcellulose (CMC) and hydroxyethylcellulose (HEC)) and acid whey cross-linked with citric acid, with the aim to obtain an agricultural product with a high swelling capacity to uphold the quality of soil and conserve water resources. With regard to the swelling behaviour of the prepared hydrogels, the authors initially assessed the swelling ratio and capacity for water uptake. Evaluating the chemical structure of the hydrogel and its thermal and viscoelastic properties involved performing Fourier transform infrared spectroscopy, differential scanning colorimetry, thermal gravimetric analysis, and rheological measurement of the hydrogel films. According to preliminary results, sufficient swelling capacity and stiffness were observed in a hydrogel prepared with 3% CMC and HEC, cross-linked with 5% citric acid. Moreover, the kinetics of water uptake revealed a promising capacity that was sustainable after 5 drying and swelling cycles. The results confirmed that the stability of the hydrogel was enhanced by the presence of the citric acid. As a consequence, it is necessary to utilize an appropriate cross-linking concentration and abide by certain conditions to ensure the swelling properties of the prepared hydrogel are sufficient. Further investigation of the topic, especially in relation to applications in soil, could confirm if the whey-cellulose-based hydrogel is actually suitable for agricultural use, thereby contributing to the advancement of sustainable arable farming.

中文翻译：

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基于可再生材料的新型农业水凝胶

这项研究详细介绍了一种新型的，可生物降解的，可再生的基于乳清/纤维素的水凝胶（即农业水凝胶）的设计和表征。它是由纤维素衍生物（羧甲基纤维素（CMC）和羟乙基纤维素（HEC））和与柠檬酸交联的酸乳清配制而成的，目的是获得具有高溶胀能力的农产品，以保持土壤质量和节约水资源。关于制得的水凝胶的溶胀行为，作者最初评估了溶胀比和吸水能力。评价水凝胶的化学结构及其热和粘弹性质涉及对水凝胶膜进行傅里叶变换红外光谱，差示扫描比色法，热重分析和流变学测量。根据初步结果，在由3％CMC和HEC制备，与5％柠檬酸交联的水凝胶中观察到了足够的溶胀能力和刚度。此外，吸水动力学揭示了有前途的容量，该容量在5个干燥和溶胀循环后可持续。结果证实，柠檬酸的存在增强了水凝胶的稳定性。结果，必须利用适当的交联浓度并遵守某些条件以确保所制备的水凝胶的溶胀性足够。对该主题的进一步研究，尤其是与在土壤中的应用有关的研究，可以确认乳清纤维素基水凝胶是否确实适合农业用途，从而有助于可持续耕作农业的发展。