Superspreading of Polyelectrolyte Complex Solution for Constructing Hydrogel Coatings on Diverse Substrates

• Published in: Advanced functional materials 2024-08, Vol.34 (33), p.n/a
• Main Authors: Wei, Congying, Zhao, Chuangqi, Ru, Yunfei, Sun, Yingzhi, Zhao, Tianyi, Qi, Shuanhu, Zhou, Jiajia, Liu, Mingjie
• Format: Article
• Language: English
• Subjects: Coatings; Coefficient of friction; Contact pressure; hydrogel coatings; Hydrogels; Interfacial properties; Liquid phases; Lubrication; Osmosis; polyelectrolyte complex solution; Polyelectrolytes; Sol-gel processes; spreading; Substrates; Surface tension; Tissue engineering; Wettability; wetting
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202400581

Injectable hydrogels have emerged as versatile materials with potential applications in various fields, including biomedicine, lubrication, adhesion, surface coatings, and tissue engineering. However, the critical aspect of spreading and wetting on various substrates, which is essential for obtaining significant interfacial properties, has not been adequately addressed. This work presents an approach to prepare hydrogel coatings on kinds of substrates through the superspreading of polyelectrolyte complex solution during its liquid‐liquid phase inversion process. Due to the low interfacial tension, the solution spreads and wets various surfaces underwater driven by osmotic pressure, improving the contact area and interface integration. Combined with the simultaneous sol‐gel transition through electrostatic interaction, it forms a stable and homogeneous hydrogel coating. The hydrogel coating possesses control thickness (4–8 µm), improved hydrophilicity (CA decrease from 102° to 10°), interfacial toughness (increase from 70 to 455 J m−2), and lubrication performance (coefficients of friction decrease from 0.712 to 0.112). The work provides an excellent opportunity to investigate the spreadability and wettability in a water/water/solid three‐phase system and develop functional hydrogel coatings for various applications. The strategy of superspreading of polyelectrolyte complex solutions on various surfaces in water/water/solid tri‐phase is developed and based on this, a hydrogel coating is constructed on a PDMS catheter. The resulting coatings not only enhance the hydrophilicity, interfacial adhesion, and lubrication but also can be further improved in terms of stability through chemical crosslinking utilizing glutaraldehyde.