Polyvinyl Alcohol/Sodium Alginate/Collagen ( PVA / SA /Col) Hydrogel Beads: Preparation of a Novel Double‐Layer Network Interpenetrating Hydrogel Material and Evaluation of Tannic Acid Adsorption Properties - Yan, Ge; Chen, Qifeng; Zhang, Lixin; Wang, Yunjia (Polymer engineering and science, 2025)