Hydrogels having enhanced elasticity and mechanical strength...

Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Cellular products or processes of preparing a cellular...

Reexamination Certificate

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C521S109100, C521S142000, C521S146000, C521S149000, C521S182000, C521S183000, C521S186000, C521S187000, C521S084100

Reexamination Certificate

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06960617

ABSTRACT:
Hydrogels having improved elasticity and mechanical strength properties are obtained by subjecting a hydrogel formulation containing a strengthening agent to chemical or physical crosslinking conditions subsequent to initial gel formation. Superporous hydrogels having improved elasticity and mechanical strength properties are similarly obtained whenever the hydrogel formulation is provided with a foaming agent. Interpenetrating networks of polymer chains comprised of primary polymer(s) and strengthening polymer(s) are thereby formed. The primary polymer affords capillary-based water sorption properties while the strengthening polymer imparts significantly enhanced mechanical strength and elasticity to the hydrogel or superporous hydrogel. Suitable strengthening agents can be natural or synthetic polymers, polyelectrolytes, or neutral, hydrophilic polymers.

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