Lifetime estimation applying a kinetic model based on the generalized logistic function to biopolymers
The aim of this work was to estimate the lifetime due thermal aging of polymers and even other materials using a new approach based on the application of a kinetic model based on the generalized logistic function. For this purpose, thermogravimetric analysis, including dynamic and isothermal tests, was performed for different formulations based on polylactic acid used in dental applications (scaffolds). In this work, lifetime is defined as the time passed for losing the 5 wt% of the mass corresponding to the first and main degradation process. The 5 mass% mass loss could be a critic parameter in manufacturing processes, in terms of economical profit and quality of the final product. The proposed model provides lifetime estimates of polymeric materials depending on the storage temperature. The present procedure permits to obtain lifetime estimates of materials characterized by more than one main degradation process, since they can be dis-overlapped using generalized logistic functions.
KeywordsLifetime Scaffolds Thermogravimetric analysis Logistic function Kinetics Biopolymers
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