Adhesive bonding of eastern hemlock glulam panels with E-glass/vinyl ester reinforcement (2)
Publication Name: Forest Products Journal
The development of novel hybrid fiber-reinforced polymer (FRP) wood composites requires the study of resin matrices not commonly associated with wood adhesive bonding. Vinyl ester resin systems are used extensively in the production of FRP composite materials due to excellent chemical resistance and tensile strength combined with low viscosity and fast curing. An efficient composite panel for decking applications is proposed by reinforcing eastern hemlock glulam panels with E-glass/vinyl ester resin face sheets. In this study, we examined the adhesive shear strength of vinyl ester resin bonded wood, and compared this to phenol resorcinol formaldehyde (PRF) bonded wood using a modified ASTM D 905 Compression Shear Test and a cyclic delamination test. A hydroxymethylated resorcinol (HMR) primer was also examined as a means to improve vinyl ester bonding with wood. Shear specimens were tested dry and tested wet after vacuum-pressure saturation. Cyclic delamination specimens were evaluated during five cycles of accelerated-aging exposure. Results indicated that vinyl ester resin with HMR primer can form strong and exterior-durable adhesive bonds with wood.