Analysis of Photo-Mechanical Response of Light Sensitive Homogeneous Hydrogels

Jafari Khoshnabadi, Mohammad Amin | 2020

299 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 53247 (08)
  4. University: Sharif University of Technology
  5. Department: Mechanical Engineering
  6. Advisor(s): Naghdabadi, Reza
  7. Abstract:
  8. Light-sensitive hydrogels are advanced materials with modern applications that have the ability to deform with light radiation at specific frequencies. Numerous studies have been conducted to identify the behavior and deformation of these materials. Most studies have experimentally investigated the light-sensitive behavior of hydrogels. On the other hand, modeling the behavior of light-sensitive hydrogels is very complicated, so that the use of these models is possible only in certain cases. Therefore, in the present study, the existing studies have been reviewed in order to simplify the relationships governing the deformation of light-sensitive hydrogels. In this regard, the deformation mechanisms of these materials including; isomerism, dimerization and ionization have been investigated. Examination of Gibbs free energy relationships and stress in light-sensitive hydrogels shows that energy can be distinguished according to the deformation mechanism in different elongation periods. Therefore, in this study, after separating the different mechanisms and periods of deformation with simplifying assumptions, the energy relations for the light-sensitive behavior of homogeneous hydrogels are presented in a simple and approximate way. Finally, by presenting the phenomenological constants along with their bounds, the complex model of the problem has become a simpler model. Simplifications in iso-dimerization mechanisms result in 1% error. The simplifying assumptions about the ionization mechanism have caused errors of 1% and 3% in the stretch range of less than 2.5 and more, respectively. In stress, the error reaches a maximum of 5%. Collective decomposition of free energy into two parts, optical and mechanical, has also been performed in this research
  9. Keywords:
  10. Modeling ; Hydrogel ; Light Intensity ; Photosensitive Material ; Swelling Behavior ; Photo-Mechanical Response

 Digital Object List