Creation of Polymer Hydrogelator/Poly(Vinyl Alcohol) Composite Molecular Hydrogel Materials

Abstract

Polymer hydrogels, including molecular hydrogels, are expected to become materials for healthcare and medical applications, but there is a need to create new functional molecular gels that can meet the required performance. In this paper, for creating new molecular hydrogel materials, the gel formation behavior and its rheological properties for the molecular gels composed of a polymer hydrogelator, poly(3-sodium sulfo-p-phenylene-terephthalamide) polymer (NaPPDT), and water-soluble polymer with the polar group, poly(vinyl alcohol) (PVA) in various concentrations were examined. Molecular hydrogel composites formed from simple mixtures of NaPPDT aqueous solutions (0.1 wt.%~1.0 wt.%) and PVA aqueous solutions exhibited thixotropic behavior in the relatively low concentration region (0.1 wt.%~1.0 wt.%) and spinnable gel formation in the dense concentration region (4.0 wt.%~8.0 wt.%) with 1.0 wt.% NaPPDT aq., showing a characteristic concentration dependence of mechanical behavior. In contrast, each single-component aqueous solution showed no such gel formation in the concentration range in the present experiments. No gel formation behavior was also observed when mixed with common anionic polymers other than NaPPDT. This improvement in gel-forming ability due to mixing may be due to the increased density of the gel’s network structure composed of hydrogelator and PVA and rigidity owing to NaPPDT.

A thixotropic molecular hydrogel composite composed of polymer hydrogelator and self-doping polyaniline copolymer for electrochromic and glucose sensing applications

“…This suggests that the presence of PASPA prevents aggregation of the NaPPDT polymer chains, resulting in thicker network components, as seen in other NaPPDT composite systems. 15,17 Although the freeze-dried process may influence the maintenance of the network structure as in the gel state by drying-induced aggregation and ice growth, 21 at least these SEM images reflect the differences in the network structure of the native gels.…”

“…Hydrogelation with doping of polyaniline systems was investigated in the polyaniline system. 11 In contrast, we have been investigating the development of composite molecular gel materials 12,13 that combine the electrical properties of polyaniline with the thixotropic properties 14 (sol–gel transition by application of external force, which is essential for gel coating properties) of molecular gels by combining water-dispersive polyaniline and water-soluble polyamide, poly(sodium-3-sulfo- p -phenyleneterephthalamide), NaPPDT (Scheme 1), 15 a polymer hydrogelator, 16 to synthesize molecular hydrogel materials for paintable electrode-active materials that are available for any shape of substrate. However, only polyaniline derivatives complexed with water-soluble polymers 17 a or phosphoric acid 17 b to improve water solubility were studied, and thus composite gels with adequate electrochemical properties were not obtained.…”

Engineered Vesicles and Hydrogel Technologies for Myocardial Regeneration

“…In addition to single components, composite hydrogels composed of multiple materials have found widespread application in EV delivery systems [101][102][103]. These composite materials overcome the specific limitations of single materials and offer the advantage of combining multiple effects.…”

Editorial for Special Issue: Advances in Smart and Tough Hydrogels

“…This ongoing pursuit underscores the continuous demand for advancements in this field, driven by the ever-evolving challenges and opportunities it presents. With this mission, Yutaka et al contributed an intriguing gelation phenomenon: the intelligent gelation occurring at low concentrations when combining the polymer hydrogelator NaPPDT with the water-soluble polymer poly(vinyl alcohol) (PVA) [1]. This unique behavior is exclusive to the NaPPDT and PVA combination, as it is not observed when mixing aqueous anionic polymer solutions with other sodium sulfonate or phosphonic acid side chains and aqueous PVA solutions.…”