We studied the strength development of the polyvinyl acetate (PVAc) adhesive joint when gluing veneer. The tested specimens were of standard dimensions, made of beech (Fagus sylvatica L.) veneer and 0.84 mm thick. They were air-conditioned at room conditions: 25 °C and 50 % humidity. We used two types of PVAc adhesives from the manufacturer Mitol, Mekol D3 and Mekol SPECIAL, which were both prepared in advance. The structural shear strength of the PVAc adhesive joint during hot pressing was achieved using the ABES instrument (Automated Bonding Evaluation System). The temperature was constant and was 80 °C. The compression time was varied for each measurement and ranged from 30 to 300 s in intervals of 30 s. We also studied the effect of 5 seconds and 30 seconds of cooling after hot compression on the final strength of the adhesive joint. The temperature rise in the adhesive joint was monitored with a thermocouple. We found that the shear strength of PVAc adhesive joints increased with the time of compression and after a certain time achieved a maximum value. The type of PVAc adhesive did not significantly affect the final strength of the adhesive joint, while in the hot-tested joints there was a difference in strength. We concluded that the test specimens, under the influence of cooling, achieved significantly higher values of the adhesive joint than the hot-tested ones. The highest shear strength of the adhesive joint was achieved with Mekol D3 adhesive under a 30 second cooling effect and was measured at 8.69 N/mm2.
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