Abstract
The influence of cross-linker (N,N-methylenebisacrylamide, MBA) and methacrylic acid (MAA) composition on the thermal stability, degradation kinetic, and lifetime, of Chitosan-based [Chitosan-poly(methacrylic acid, (Cs-PMAA)] dual responsive hydrogels was investigated in detail using the Flynn-Wall-Ozawa (F-W-O) method. The Cs-MM-MBA derivatives showed only a glass transition temperature (T-g) that increased as the content of MAA increased. The stability of Cs-MM-MBA has been achieved at a critical point where the MAA content was 300 mg/ml and MBA was 15 mg/ml. The lifetime of Cs-PMAA hydrogels (time at 5% mass loss) was estimated by increased temperature delivery in nitrogen atmosphere. On average, a higher E-a has been attributed to the greater cross-linking density of Cs hydrogel. Likewise, the lower swelling ability of Cs hydrogel can be due to the slower relaxation rate of the polymer chain, which then results in an increased lifetime of the potential drug-release rate. (C) 2014 Elsevier B.V. All rights reserved.