title: Bulk modulus of poly(N-isopropylacrylamide) microgels through the swelling transition.
abstract: We report measurements of the bulk modulus of individual poly(N-isopropylacrylamide) microgels along their swelling transition. The modulus is determined by measuring the volume deformation of the microgel as a function of osmotic pressure using dextran solutions. We find that the modulus softens through the transition, displaying a nonmonotonous behavior with temperature. This feature is correctly reproduced by the theory of Flory for polymer gels, once the concentration dependence of the solvency parameter is properly incorporated.
authors.affiliation: School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
authors.forename: B
authors.initials: B
authors.lastname: Sierra-Martín
authors.forename: Y
authors.initials: Y
authors.lastname: Laporte
authors.forename: A B
authors.initials: AB
authors.lastname: South
authors.forename: L A
authors.initials: LA
authors.lastname: Lyon
authors.forename: A
authors.initials: A
authors.lastname: Fernández-Nieves
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins; D001703:Biophysics / Q000379:methods; D003432:Cross-Linking Reagents / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D055119:Elastic Modulus; D004548:Elasticity; D005609:Free Radicals; D005782:Gels; D009995:Osmosis; D010825:Physics / Q000379:methods; D011108:Polymers / Q000737:chemistry*; D011312:Pressure; D012212:Rheology; D012997:Solvents / Q000737:chemistry; D013696:Temperature
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D003432:Cross-Linking Reagents; D003911:Dextrans; D005609:Free Radicals; D005782:Gels; D011108:Polymers; D012997:Solvents; C052970:poly-N-isopropylacrylamide