Plywood laminate adhesives testing

Metal-to-metal laminate test for large bonded areas but may also be used with plastic subsfiates Specifically for adhesives used in plywood laminate constructions Specifically for wooden (two-ply) laminate substrates... 

Plywood panels produced in Europe for building purposes use urea-formaldehyde (UF), melamine-urea-formaldehyde (MUF) and phenol-formaldehyde (PF) adhesives. Standards requirements are not focused on direct properties of these adhesives but properties of the end-products (closely linked to adhesive properties and process parameters). Nevertheless, EN 314-1 (2005) [1] defines a test method for the evaluation of the bonding quality of plywood panels, but also blockboards, laminated boards and laminated veneer lumbers (LVL), by shear testing before and after ageing treatments. Relevant requirements are specified in EN 314-2 (1993) [5] which also defines the ageing treatments required for the intended service class of the tested panel as shown in Table 1. 

D-3024. Specification for Protein-Base Adhesives for Structural Laminated Wood Products for Use Under Interior (Diy Use) Exposure Conditions. Employs the D-0>905 block shear, D-0906 plywood shear, and D-4300 mold resistance tests to evaluate mostly casein-base adhesives for use in interior grade laminated beams. 

In D-3024 (see wood adhesive specifications), samples of laminated wood and plywood are tested both before and after water exposure and variously evaluated for shear strength and/or wood failure. These procedures could have applications in other wood glue testing as well. 

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