Thermal Degradation and Kinetics of Alginate Polyurethane Hybrid Material Prepared from Alginic Acid as a Polyol

摘要

Alginate polyurethane hybrid materials are prepared by varying mole ratio of 2, 4-TDI as a di-isocy-anate and alginic acid as a polyol in presence of dimethyl sulfoxide (DMSO) as a solvent. FT-IR and ~(13)C one-dimensional (ID) solid state NMR (SSNMR) spectroscopy indicates that alginic acid is converted into alginate-poly-urethane hybrid material via urethane linkage. Surface morphology of alginate-polyurethane hybrids changes by varying alginic acid: TDI ratio. The peak at near 221 ℃ in DSC thermogram of alginic acid (Alg) is shifted to higher temperature in alginate-polyurethane hybrid (Algpul and Algpu2). TGA study shows that alginate-polyurethane hybrid prepared using alginic acid: TDI =1:1 (Algpu2) is more stable than alginic acid: TDI = 1:0.5 (Algpul) at 300 ℃. Kinetic analysis was performed to fit with TGA data, where the entire degradation process has been considered as three consecutive 1st order reactions. This study shows that thermal stability of alginate-polyurethane hybrid material was increased by adjusting mole ratio of 2, 4-TDI and alginic acid.