title: Rapid deswelling response of poly(N-isopropylacrylamide)/poly(2-alkyl-2-oxazoline)/poly(2-hydroxyethyl methacrylate) hydrogels.
abstract: Ternary poly( N-isopropylacrylamide)/poly(2-alkyl-2-oxazoline)/poly(2-hydroxyethyl methacrylate) (PNIPAAm/PROZO/PHEMA) hydrogels were prepared by the free-radical copolymerization of N-isopropylacrylamide (NIPAAm), 2-hydroxyethyl methacrylate (HEMA), and poly(2-alkyl-2-oxazoline) (PROZO) multifunctional macromonomers. The resulting polymeric materials were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), as well as by equilibrium swelling experiments. All synthesized hydrogels display temperature sensitivity in the 28-38 degrees C range. A high rate of response was registered as compared to that of materials based only on PNIPAAm. The swelling-deswelling peculiar behavior was related to the chemical composition (hydrophile/hydrophobe balance), the length of the inserted PROZO sequence, and inner morphology, an aspect which points on its possible control by synthesis. It was evidenced that the architecture of the resulting porous materials has a high order degree, emerging from the self-assembling of the microgel particles, which provided numerous, nearly uniform, large water release channels.
authors.affiliation: Department of Natural and Synthetic Polymers, Gh. Asachi Technical University, Iasi, 700050, Romania. geta_david2000@yahoo.com
authors.forename: Geta
authors.initials: G
authors.lastname: David
authors.forename: Bogdan C
authors.initials: BC
authors.lastname: Simionescu
authors.forename: Ann-Christine
authors.initials: AC
authors.lastname: Albertsson
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D020100:Hydrogels / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010080:Oxazoles / Q000737:chemistry*; D011102:Polyhydroxyethyl Methacrylate / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000378:metabolism; D013696:Temperature
chemical_list: D000180:Acrylic Resins; D020100:Hydrogels; D010080:Oxazoles; C052970:poly-N-isopropylacrylamide; D011102:Polyhydroxyethyl Methacrylate; D012710:Serum Albumin, Bovine