Urethane hydrogels

Unsaturated polyester resins (UPRs) Uralkyd resins, 202 Urea-methylol reaction, 410 Urethane alkyds, 241 Urethane coatings, 202 Urethane elastomers, implanted, 207 Urethane foams, tests for, 244 Urethane gels, 205 Urethane-grade ATPEs, 223 Urethane-grade polyol types, 212 Urethane-grade raw materials, 246 Urethane hydrogel, preparation of, 250-251... 

Polyurethane hydrogels derived from UV curable urethane prepolymer and hydrophilic monomers were prepared and their properties were evaluated. The urethane prepolymer used in this study contained well-defined hard segments centered with a polyether-based soft segment and end-capped with methacrylate groups. The hydrophilic monomers studied were 2-hydroxyethyl methacrylate (HEMA), N-vinyl pyrrolidone, and glycerol methacrylate. Methacryloxypropyl tris(trimethysiloxy) silane (TRIS) was also used in some cases to modify properties. All compositions were UV... 

Hubbell [2] prepared biocompatible hydrogels consisting of poly(acrylic acid-b-ethylene oxide) crosslinked with hydrolytically susceptible carbonates, (IV), urethanes, (V), ureas, (VI), ester amides, (VII), and diamides, (VIII). 

Fig. 5 Representation of temperature-controlled protein release from poly(PEG/PPG/PCL urethane) hydrogel...

Hydrogel Formation from Copolyether—Urethane—Ureas Salt Complex... 

Earlier, we reported that complexes of lithium bromide (LiBr) with copolyether-urethane-ureas led to the formation of hydrogels (6). The water absorption curves for these hydrogels indicated the existence of two modes of absorption an initial water absorption that depended on the concentration ratio of LiBr to the urethane-urea segment (hard segment) of the block copolymer, and the water uptake at higher salt concentration which was attributed to the formation of voids in the film. 

Figure 22.13 Preparation of CMC hydrogels modified with polyfester-urethane) (reprinted with permission of Kadnaim et al., 2008, Elsevier [6]).

Kadnaim, A., Janvikul, W., Wichai, U., Rutnakornpituk, M. (2008). Synthesis and properties of carboxymethylchitosan hydrogels modified with poly(ester-urethane), Carboh rdr Qj, 74, 257-267. 

IPNs and gradient IPNs based on polyether-urethane-urea (PEUU) block copolymers and acrylamide, 2-hydroxyethyl methacrylate (HEMA), or N-vinyl-2-pyrrolidone. Intended for biomedical uses, such compositions created high-strength, water-absorbing hydrogel surfaces showing good blood compatibility. 

G. C. Berry and M. Dror, Modification of Polyurethanes by Interpenetrating Polymer Network Formation with Hydrogels, Am. Chem. Soc. Div. Org. Coat. Plast. Chem. Pap. 38(1), 465 (1978). Polyether-urethane-urea block copolymers with crosslinked HEMA, NVP, or acrylamide. IPNs and gradient IPNs for biomedical purposes. Strength, water swellability, and good blood compatibility. 

K. Manokruang, J.S. Lym, D.S. Lee, Injectable hydrogels based on poly(amino urethane) conjugated bovine serum albumin. Mater. Lett. 124 (2014) 105-109. 

Trehalose tetraesters characterised by ID and 2D H and C NMR and ESI-MS as biosurfactants (rather than cryoprotectants) were isolated from a soil strain of Micrococcus luteus. Solubilisation of phenol within mieellar aggregates of hexadecyltrimethylammonium bromide (HTAB) in aqueous solutions were investigated by H NMR in D20. The synthesis and properties of non-cytotoxic carboxymethylcellulose-chitosan hydrogels modified with poly(ester-urethane) was reported. 2D NOE NMR gave new insights into the interactions between polyamidoamine dendrimers and different surfactants including SDS and dodecyltrimethylammonium bromide. The ability of a- and (3-CDs to disrupt a surfactant mixed micelle of an equimolar mixture of octyltriethylammonium bromide (OTEAB) and sodium perfluorooctanoate (SPFO) was studied by H and F NMR. The effect of ethanol on the micellization of SDS (anionic... 

To improve the mechanical compatibility between the hydrogel and the fabrics, Hu et incorporated urethane moieties into PNIPPAm... 

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