Manaila Elena, Craciun Gabriela
Electron Accelerators Laboratory, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., 077125 Magurele, Romania.
Gels. 2024 Sep 23;10(9):609. doi: 10.3390/gels10090609.
Hybrid hydrogels with superabsorbent properties based on acrylic acid (20%), sodium alginate (0.5%) and poly(ethylene oxide) (0.1%) were obtained by electron-beam irradiation between 5 and 20 kGy, and are characterized by different physical and chemical methods; the first results reported showed gel fractions over 87%, cross-link densities under 9.9 × 10 mol/cm and swelling degrees of 400 g/g. Two types of hydrogels (without and with 0.1% initiator potassium persulfate) have been subjected to swelling and deswelling experiments in different swelling media with different pHs, chosen in accordance with the purpose for which these superabsorbent materials were obtained, i.e., water and nutrients carriers for agricultural purposes: 6.05 (distilled water), 7.66 (tap water), 5.40 (synthetic nutrient solution) and 7.45 (organic nutrient solution). Swelling kinetics and swelling dynamics have been also studied in order to investigate the influence of swelling media type and pH on the absorption phenomenon. The swelling and deswelling behaviors were influenced by the hydrogel characteristics and pH of the swelling media. Both the polymeric chain relaxation (non-Fickian diffusion) and macromolecular relaxation (super case II) phenomenon were highlighted as a function of swelling media type.
基于丙烯酸（20%）、海藻酸钠（0.5%）和聚环氧乙烷（0.1%）的具有高吸水性的混合水凝胶通过5至20千戈瑞的电子束辐照获得，并采用不同的物理和化学方法进行表征；首次报道的结果显示凝胶分数超过87%，交联密度低于9.9×10摩尔/立方厘米，溶胀度为400克/克。两种类型的水凝胶（不含和含有0.1%引发剂过硫酸钾）在不同pH值的不同溶胀介质中进行了溶胀和去溶胀实验，这些溶胀介质根据获得这些高吸水性材料的目的进行选择，即用于农业目的的水和养分载体：6.05（蒸馏水）、7.66（自来水）、5.40（合成营养液）和7.45（有机营养液）。还研究了溶胀动力学和溶胀动力学，以研究溶胀介质类型和pH值对吸收现象的影响。溶胀和去溶胀行为受水凝胶特性和溶胀介质pH值的影响。作为溶胀介质类型的函数，聚合物链松弛（非菲克扩散）和大分子松弛（超情况II）现象均得到了突出体现。
