1Nano-Biopolymer Research Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran, Iran
2Nano-Biopolymers Research Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
چکیده
Liquid crystal elastomers (LCEs) are a special class of materials including liquid crystalline arrangement and cross-linked polymer network phases. The simultaneous presence of these properties, unique mechanical and optical properties can be happened in LCEs, thereby having wide biological applications. The aim of this work is to synthesize LCEs based on thiol-acrylate Michael addition reaction, to investigate their crosslinking trend and its effect on glass transition temperature (Tg) using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC), respectively. By considering the FITR results, it has been found that the characteristic peak intensity of thiol groups at wavenumber approximately 2600 cm-1 is decreased due to their contribution in crosslinking process. Interestingly, this decline trend is immense for the sample crosslinked by ultra violet (UV) irradiation. On the other hand, the DSC thermograms of the samples show an increase behaviour in their Tg by increasing the crosslinker content. The optimum sample with Tg value approximately -7℃ is obtained while adjusting the crosslinker content to 75 wt. %. Finally, the obtained results reveal that the variation of crosslinker content is a key role on the polymerization process of LCE samples.
