Hydrogels hydrophobic interactions

PNIPAAm-based hydrogel Hydrophobic interaction Temperature [30]... 

Several other studies have also been made in an attempt to account theoretically for the phase transition in terms different from those of the Flory-Huggins theory. Otake et al. [55] thus proposed a theoretical model that takes hydrophobic interaction into account in explaining the thermally induced discontinuous volume collapse of hydrogels. In addition, Prausnitz et al. [56] proposed a lattice model, an improvement of which was made to explain the swelling curves of gels consisting of /V,/V -methylenebis(acrylamide) (MBA)-crosslinked copolymers of AAm with [(methacrylamide)propyl]trimethyl-ammonium chloride (MAPTAC) [57],... 

These can be immobilized by either electrostatic adsorption on ion-exchangers [81] or sulfonated polystyrene [82], by hydrophobic interactions on organic polymers [83], by covalent binding to cellulose [68,84] and chloro-sulfonated polystyrene [71], or by entrapment in hydrogels [69,85]. Sol-gel based methods were established particularly for the preparation of fiber optic sensors [86-88]. 

Xing BG, Yu CW, Chow KH et al. (2002) Hydrophobic interaction and hydrogen bonding cooperatively confer a vancomycin hydrogel a potential candidate for biomaterials. J Am Chem Soc 124 14846-14847... 

Fig. 16 CDs as rheology modifiers addition of CD reduces viscosity because it breaks intermolecular hydrophobic interactions addition of SDS (sodium do-decyl sulfate) regenerates the original hydrogel [192,193]...

Fig. 1 Representative methods of hydrogel formation. (A) Chemically cross-linked hydrogels are prepared from monomers, oligomers, or polymers in the presence of cross-linking agents. The chemical cross-linking proceeds via radical polymerization or polycondensation reaction. (B) Physically cross-linked hydrogels can be formed by ionic interactions, hydrophobic interaction, or hydrogen bonding.

Yakushiji T, Sakai K, Kikuchi A, Aoyagi T, Sakurai Y, Okano T. Effects of cross-linked structure on temperature-responsive hydrophobic interaction of PIPAAm hydrogel modified surfaces with steroids. Anal Chem 1999 71(6) 1125-1130. 

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