Improved mechanical properties of superporous hydrogels

Yong Qiu, Purdue University

Abstract

The purpose of the present study was to improve the mechanical properties of superporous hydrogels. The main approach used in this study was forming interpenetrating polymer networks by incorporating a second polymer network inside the superporous hydrogel structures. Synthetic polyacrylonitrile polymer and polysaccharides were used to penetrate inside the superporous hydrogels. Mechanical properties, including compression strength and elasticity, were significantly improved. The swelling capacities of the resultant IPN hydrogels were decreased, whereas the swelling speed was still very fast, ranging from 2–4 minutes. The macroscopic properties including swelling behavior and mechanical improvements were all well explained by the microscopic structures. Various scaffold-like fiber network structures were observed along or connecting the cell walls of superporous hydrogel pores. Restrictions on volume swelling ratio were observed universally for various types of superporous IPN hydrogels. The existence of the scaffold-like polymer networks enforced a restraint on the volume change upon hydrogel swelling, which is essentially the extension limit of the incorporated polymer networks in water. The elasticity of superporous hydrogels is improved tremendously by the polysaccharide hybrids approach. Depending on the type of polysaccharide strengtheners used, the superporous hydrogel hybrids can be stretched to about 200% to 300% elongation of their original length. Such elasticity has never been reported on any hydrogels. The applications of superporous hydrogels could be greatly broadened by such improvement in mechanical properties.

Degree

Ph.D.

Advisors

Park, Purdue University.

Subject Area

Pharmaceuticals

COinS