| 摘要 |
The invention provides translucent, water-insoluble hydrogel compositions and methods of making them. The hydrogel compositions comprise a polyvinyl alcohol polymer and a complexing agent which are physically crosslinked to form a semi-crystalline polyvinyl alcohol-complexing agent polymer complex. The hydrogel compositions may be prepared by: (i) combining a polyvinyl alcohol polymer with a suitable aprotic solvent; (ii) Adding a complexing agent to (i) to form a water soluble complex with the polyvinyl alcohol polymer; and (iii) Allowing the polyvinyl alcohol polymer and the complexing agent to form a water-insoluble, semi-crystalline structure. The formation of the semi-crystalline structure is assisted by freezing the polyvinyl alcohol/complexing agent/polar aprotic solvent mixture. The hydrogel compositions are translucent or transparent. They exhibit relatively high stress strength and low oxygen permeability. They are particularly suitable for use as wound dressings for skin wounds, especially burn wounds. For such applications, therapeutic additives, e.g. allantoin, may advantageously be included in the hydrogel compositions. |
