Thesis Defense Gabrielle Boivin- Thursday, September 19th at 9am!
You are cordially invited to attend the thesis defense of Gabrielle Boivin, Ph.D. student in Chemistry, which will take place on Thursday, September 19, 2024 at 9 a.m. in room GHK-2320-2330. Everyone is welcome!
When and where?
September 19, 2024 at 9 a.m.
Gene-H.-Kruger Pavilion
Room GHK-2320-2330 (Gilbert-Tardif room)
2425 de la Terrasse Street
Laval University, Quebec City
Jury members are :
Paul A. Johnson, Jury Chairman and Secretary – Department of Chemistry, Laval University
Jean-Yves Bergeron, external examiner- Kemitek
Josée Brisson, examiner- Department of Chemistry, Laval University
Jean-François Morin, examiner- Department of Chemistry, Laval University
Anna Ritcey, Research Director- Department of Chemistry, Laval University
Véronic Landry, Co-Research Director- Department of Wood and Forest Sciences, Laval University
Thesis title: Preparation of functional coatings for wood by incorporating nanoparticles during mini-emulsion polymerization
Abstract:
Exterior wood products protected with translucent finishes require frequent maintenance and have a shorter service life than competitive materials, which disadvantages wood in outdoor applications. Developing high-performance, durable, and low-maintenance finishing products is essential. This PhD thesis investigates using mini-emulsion polymerization to develop translucent wood finishes with antifungal and photodegradation-resistant properties, by encapsulating nanoparticles in the polymer matrix.
Silver and zinc oxide nanoparticles were synthesized and encapsulated in acrylic latexes by mini-emulsion polymerization. The antifungal properties of finishes prepared from the synthesized latexes were evaluated against strains of Sclerophoma pityophila, Epicoccum nigrum and Aureobasidium pullulans. Latexes containing silver nanoparticles (AgNPs) were shown to limit the growth of S. pityophila and E. nigrum as effectively as the reference formulation after eight weeks. However, it was more difficult to control the growth of the A. pullulans strain.In addition, the thesis reports on the influence of the type of initiator (hydrophobic or hydrophilic) on the incorporation and distribution of AgNPs in the synthesized polymer particles, as well as on the antifungal properties.The influence of initiator type on the leaching of encapsulated AgNPs by miniemulsion polymerization was also investigated.
This thesis work shows that mini-emulsion polymerization can be used to prepare acrylic latexes resistant to black-stain fungi by encapsulating AgNPs. Mini-emulsion polymerization could also be used as a potential means of reducing the leaching of additives into the environment.