A performance-based standard has recently been published to evaluate new structural adhesives not covered by other standards for “wet” use applications. A parallel standard is being developed for “limited exposure” applications. Concerns have been expressed, by manufacturers of adhesives and producers of engineered wood products, that traditional protocols and criteria may not be appropriate for the new standard.
This project will evaluate the appropriateness of the use of block shear strength and percent wood failure and their acceptance levels for both wet and dry use applications, and make recommendations on how these protocols and criteria should be modified to more realistically reflect the performance requirements of selected end products for strength and durability of bond line. This project is linked to the completed Forintek project titled: Review of Standard Test Procedures for Assessing Delamination Resistance of Solid Wood Bondlines, and the ongoing Forintek project titled: Characterization of Resin Penetration and Its Relationship with Wood Failure and Shear Bonding Strength for Various Structural Adhesives.
develop techniques for directly quantifying wood-adhesive bond force, adhesive penetration in wood, and degree of resin curing using advanced analytical techniques;
correlate wood-adhesive interaction parameters with percent wood failure and block shear strength of specimens prepared under dry and “aged” conditions.
recommend, if appropriate, alternate means of evaluating new structural adhesives for strength requirements.