title: Preparation of macroporous poly(2-hydroxyethyl methacrylate) hydrogels by enhanced phase separation.
abstract: Macroporous poly(2-hydroxyethyl methacrylate) (p(HEMA)) hydrogels were prepared in the presence of a 0.3-0.7 M NaCl solution. The pore morphology of the p(HEMA) hydrogels was dependent on the concentration of NaCl for a constant monomer solution to aqueous solution ratio. Swelling studies showed an increase in equilibrium water content and hydrogel porosity as the NaCl concentration in the polymerization medium increased from 0 to 0.7 M. The equilibrium water content, however, decreased as the NaCl concentration in the swelling medium increased. The frozen water content increased and non-frozen water decreased with an increase in the NaCl concentration in the polymerization medium. Mechanical testing indicated that the elastic modulus of the hydrogels was not affected by the increased porosity until the pores became interconnected. These data suggest that the addition of NaCl to the polymerization medium results in a multi-phase separation during fabrication that produces macroporous hydrogels of controlled morphology.
authors.affiliation: Department of Bioengineering, Rice University, Houston, TX 77251-1892, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Liu
authors.forename: E L
authors.initials: EL
authors.lastname: Hedberg
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
authors.forename: R
authors.initials: R
authors.lastname: Bahulekar
authors.forename: R K
authors.initials: RK
authors.lastname: Meszlenyi
authors.forename: A G
authors.initials: AG
authors.lastname: Mikos
mesh_terms: D002152:Calorimetry, Differential Scanning; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003890:Desiccation; D004548:Elasticity; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011102:Polyhydroxyethyl Methacrylate / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D011108:Polymers; D016062:Porosity; D012462:Saline Solution, Hypertonic; D012997:Solvents; D014466:Ultraviolet Rays; D014867:Water
chemical_list: D020100:Hydrogels; D011108:Polymers; D012462:Saline Solution, Hypertonic; D012997:Solvents; D014867:Water; D011102:Polyhydroxyethyl Methacrylate