Chloé Paquet’s thesis defense – May 2 in person
29 April 2022
You are cordially invited to attend Chloé Paquet’s PhD thesis defense in wood and bio-based materials engineering, which will take place in person on May 2 at 9:00 am (Quebec City time). Please note that the guests will have to keep their masks on during the whole defense.
Where and When?
May 2, 2022 at 9:00 am
Gene H. Kruger Pavilion, room 2320-2330
2425, Rue de la Terrasse
Laval University, Quebec
It will also be possible to attend the defense virtually through Zoom at the following link: https://ulaval.zoom.us/j/68231024447?pwd=Qy83MnFDRHdlVU9ySTh5V1pmYkNGdz09
MEMBERS OF THE JURY
President
André Desrochers
Faculty of Forestry, Geography and Geomatics
Examiners
Véronic Landry, research director
Faculty of Forestry, Geography and Geomatics
Jean-François Morin, co-director of research
Faculty of Science and Engineering
Gelareh Momen, examiner
University of Quebec at Chicoutimi
Anna Ritcey, Examiner
Faculty of Science and Engineering
Pierre Blanchet
Faculty of Forestry, Geography and Geomatics
A summary of Ms. Paquet’s research can be found below:
Development of Self-Repairing UV Cured Coatings for the Finishing of Wood Appearance Products
In order to increase the use of wood in buildings, it is important to push the limits of its properties. In the area of interior wood products, surface strength is the key parameter to optimize. In the case of wood flooring, abrasion and scratch resistance is essential, as it is subject to repeated mechanical stress. The solvent-free finishing system based on UV light-curable acrylates provides this protection for wood flooring. Despite its performance, the appearance of scratches after a mechanical attack is inevitable. A new approach is being considered to increase their life span, that of conferring on the finishing system the property of self-repair.
Two technologies are studied during this thesis. The first is the synthesis of capsules containing a self-repairing agent. Several systems have been tested, such as urea-aldehyde capsules, isocyanate-free polyurethane capsules, and the synthesis of biobased isocyanates into biobased polyurethane capsules. However, despite important advances such as the synthesis of an isocyanate-free polyurethane, no capsules have been obtained.
The second is the development of new acrylate formulations containing hydrogen bonds. For this purpose, acrylate formulations have been developed with monomers and oligomers bearing hydroxyl groups. To meet the requirements of the wood flooring application, the hardness and cure rate of the coatings were evaluated, as well as their physicochemical properties. The self-repair efficiency was evaluated on different types of scratches and several promising formulations were developed. They combine a self-repair of more than 90%, a high cross-linking density, and a thermal repair stimulus below 100°C, thanks to low steric hindrance components.