Miscibility and influence on each other of a UV photo-initiated thermosetting polymer blend of radical and cationic systems

Lefebvre, Kevin, "Miscibility and influence on each other of a UV photo-initiated thermosetting polymer blend of radical and cationic systems" (2013). Thermoset blends engage an interest into polymer materials using photopolymerization. Our work is inscribed within a project which consists to control the degree of crosslinking in three dimensions during UV photo-curing. Two different reaction mechanisms were considered to enlarge the control of properties. The goal of this thesis was to check the miscibility between two thermosetting polymers using radical and cationic chemical mechanisms. Then their influence on each other was studied by thermal analysis. The experimental system was Bisphenol A propoxylate diacrylate for the radical curing and 3,4-epoxycyclohexylmethyl 3,4-cyclohexanecarboxylate for the cationic. They were initiated by 2-hydroxy-2-methylpropiophenone and Triarylsulfonium hexafluoroantimonate salts mixed respectively. Several polymer blends were manufactured and influence of weight proportions and process temperature were studied. As a result, high thermal stability and properties were determined and homogeneity of these materials was verified by Thermogravimetric Analysis. Differential Scanning Calorimetry showed that thermal properties of blended materials didn't follow any linear blending law. It was also noticed that the temperature needs to be highly considered. The cationic resin, which used to be post-cured to reach a high degree of curing, was highly cured at 80°C. But the radical network, which used to crosslink very fast at ambient temperature, didn't fully cure. We concluded that some interactions occur between the two systems but the presence of Interpenetrating Polymer Networks was not confirmed. iii Acknowledgments I would like to thank everyone who helped me and shared my life during my master's degree. My first personal acknowledgment goes to Dr. Tan. Li, there is no word to express you all my thankfulness, gratitude and respect. Even though we sometimes had a hard time to get along together, I truly appreciated your advices and your way to share your experience. Thank you for helping me to find myself and get more self-confident. Dr. Negahban, thank you for your directions, your help and your reassurance all along my experience in your department. Dr. Saiter, I can never thank you enough for allowing and pushing me to take part of this program. This amazing experience made me more open-minded and grown up. To Dr. Delpouve, thank you so much for your managing, your patience and sharing your passion. Your directions helped me to be more organized and enjoy my work better. Thank you to …