McCann Krystal, Knudsen Bernard, Ananthoji Ramakanth, Perry John J, Hilker Brent, Zaworotko Michael J, Harmon Julie P
University of South Florida, 4202 E Fowler Avenue, Tampa, FL 33620, USA.
J Nanosci Nanotechnol. 2010 Sep;10(9):5557-69. doi: 10.1166/jnn.2010.2498.
2-hydroxyethyl methacrylate (HEMA) and 2,3-dihydroxypropyl methacrylate (DHPMA) were used to synthesize novel nanocomposites containing 0.5% by weight of copper hydroxylated nanoballs. Glass transition temperatures of the copolymers and their respective nanocomposites were determined by using differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) was employed to measure the degradation temperatures of the samples and to determine if the degradation is a single step process or multiple step process. The dielectric permittivity (epsilon') and loss factor (epsilon") were measured via Dielectric Analysis (DEA) in the frequency range 0.1 Hz to 100 kHz and between the temperature -150 to 190 degrees C. gamma, beta, and alphabeta conductivity relaxations were revealed using the electric modulus formalism. The activation energies for the relaxations were calculated. Argand plots of M" versus M' were used to study the viscoelastic effects of both copolymer and the composites. Herein we show that it is possible to tune solubility and relaxation properties which are important to the design of new biomaterials.