Synthesis and Properties of Polyurethane-Urea-Based Liquid Bandage Materials

To obtain ideal liquid bandage polymer materials, a series of polyurethane-urea dispersions were synthesized from 4,4'-diisocyanato dicyclohexylmethane (H12MDI) and ethylene diamine with different molar ratio of polyol blend [polyethylene glycol (PEG, M-n = 2000 g/mol)/hydroxy terminated poly(dimethylsiloxane) (PDMS, M-n = similar to 550 g/mol)] and acetone/ethanol as a solvent. The effect of PDMS content in PEG/PDMS on the viscosity, mechanical properties, water contact angle/surface energy, insolubility in water (%), water absorption (%), equilibrium water content (%), and water vapor transmission rate (g m(-2) day(-1)) of polyurethane-urea films was investigated. As PDMS content increased, the water contact angle, insolubility in water, and tensile strength/elastic recovery of film sample increased; however, the surface energy, water absorption (%), equilibrium water content (%), and water vapor transmission rate (g m(-2) day(-1)) of film sample decreased. By a wound-healing evaluation using a full-thickness rat model experiment, it was found that a wound covered with a typical polyurethane-urea liquid bandage film (PD2 sample) was filled with new epithelium without any significant adverse reactions. These results suggest that the polyurethane-urea-based liquid bandages (samples: PD2 and PD3) prepared in this study may have high potential as new wound dressing materials, which provide and maintain the adequate wet environment required to prevent scab formation and dehydration of the wound bed. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3516-3524, 2011