UV‐Induced Cross‐Linking of Poly(ethylene oxide) in Aqueous Solution

Abstract

Summary: Hydrogels of high‐molecular‐weight poly(ethylene oxide) (PEO) have been obtained in situ by applying a very simple procedure that involves UV cross‐linking of PEO in aqueous solution. The efficiency of the photoactivated cross‐linking of thin layers of PEO in aqueous solution in the presence of (4‐benzoylbenzyl) trimethylammonium chloride as a photoinitiator has been determined at room temperature and in a frozen state (−25 °C). It was found that the efficiency varies with the concentration of PEO solution, the molecular weight of PEO, and especially with the temperature. When the UV cross‐linking was performed in the frozen state, porous hydrogels with very high yield of gel fraction (above 90%) and high cross‐linking density were obtained. After drying the hydrogels, films of 50–150 μm thickness were prepared. The films swell extremely fast in water and act as asymmetric membranes.

X-ray Spectromicroscopy Study of Protein Adsorption to a Polystyrene−Polylactide Blend

“…UV-initiated crosslinking of PEO with pentaerythritol triacrylate (PETA) or other radical crosslinkers [8] is becoming increasingly popular since PEO can be crosslinked in both solution and solid state [9,10]. The inclusion of PETA to form crosslinked PEO has been used in biomedical applications such as hydrogels [11,12] and micelles [13] for drug delivery, or to form chemically patterned surfaces for cell studies [14].…”

Cryogels via UV Irradiation

“…Notably, the crosslinking reaction is very fast and formation of the polymer network can be completed within several minutes. The accepted mechanism of crosslinking of high molar mass linear polymers induced by UV light involves generation and subsequent recombination of macroradicals [10] with the aid of a photoinitiator. A substantial advantage of this method is the fact that no functional groups are required.…”

“…Ten years ago, the UV irradiation technique was successfully employed for the first time by our team for the synthesis of poly(ethylene oxide) (PEO) cryogels [10]. This method starts with freezing of the solvent and conducts the crosslinking reaction after the complete structuring of the system.…”

Biosurfactant Production by Pseudomonas aeruginosa BN10 Cells Entrapped in Cryogels

“…In particular, the synthesis of cryogels via UV irradiation appears to be a very fast and effi cient approach which can be set up at low cost (Doycheva et al, 2004;Petrov et al 2006Petrov et al , 2007. This method allows preparation of various biocompatible, biodegradable, and/or thermosensitive supermacroporous cryogels by irradiation of moderately frozen aqueous systems with UV light (irradiation dose rate of 950 J m -2 s -1 ) for 2 -5 minutes in the presence of a photoinitiator.…”