Self-Healing UV-Curable Acrylate Coatings for Wood Finishing System, Part 2: Impact of Monomer Structure and Self-Healing Parameters on Self-Healing Efficiency

Coatings

Jean-François Morin¹  Stephen Brown²  Jolanta E. Klemberg-Sapieha²  Chloé Paquet³  Véronic Landry³ 

[1] Département de Chimie, Centre de Recherche sur les Matériaux Avancés (CERMA), Université Laval, Québec, QC G1V 0A6, Canada;Département de Génie Physique, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada;Département des Sciences du Bois et de la Forêt, Chaire de Recherche Industrielle CRSNG–Canlak en Finition des Produits du Bois D’Intérieur (CRIF), Université Laval, Québec, QC G1V 0A6, Canada;

关键词: acrylate;    UV curable;    self-healing;    hydrogen bonds;    crosslinking;   

DOI  :  10.3390/coatings11111328

来源: DOAJ

【 摘 要 】

Wood is increasingly used in construction for the benefits it brings to occupants and for its ecological aspect. Indoor wood products are frequently subject to mechanical aggressions, their abrasion and scratch resistance thus need to be improved. The coating system ensures the wood surface protection, which is, for wood flooring, a multilayer acrylate UV-curable 100% solid system. To increase the service life of wood flooring, a new property is studied: self-healing. The objective of this study is to observe the impact of monomer structure on self-healing efficiency and the effect of self-healing parameters. A previous formulation was developed using hydrogen bond technology to generate the self-healing property. In this paper, the assessment of the formulation and the self-healing parameters’ impact on self-healing efficiency as well as the physicochemical properties are presented. The composition of the monomer part in the formulations was varied, and the effect on the conversion yield (measured by FT-IR), on the T_g and crosslinking density (measured by DMA) and on mechanical resistance (evaluated via hardness pendulum, indentation, and reverse impact) was analyzed. The self-healing efficiency of the coatings was determined by gloss and scratch depth measurements (under constant and progressive load). It was proven that monomers with three acrylate functions bring too much crosslinking, which inhibits the chain mobility necessary to observe self-healing. The presence of the AHPMA monomer in the formulation permits considerably increasing the crosslinking density (CLD) while keeping good self-healing efficiency. It was also observed that the self-healing behavior of the coatings is different according to the damage caused. Indeed, the self-healing results after abrasion and after scratch (under constant or progressive load) are different. In conclusion, it is possible to increase CLD while keeping self-healing behavior until a certain limit and with a linear monomer structure to avoid steric hindrance. Moreover, the selection of the best coatings (the one with the highest self-healing) depends on the damage.

【 授权许可】

Unknown