Manufacturing of shuttering panels with adhesive, based on liquefied wood and melamine-urea-formaldehyde (MUF), was examined. We identified the structure of adhesive mixture satisfying the different usage conditions of shuttering panels: dry conditions, humid conditions and exterior conditions. We prepared 5 adhesive mixtures, with varying proportions of MUF adhesive and liquefied wood (MUF/LW): 100/0, 90/10, 80/20, 70/30, 60/40. We manufactured shuttering panels (500 mm x 500 mm x 27 mm) with these adhesive mixtures. The shear test pieces were cut and prepared according to the conditions of use. Then we tested the effect of the share of liquefied wood in adhesive mixture on the shear strength of adhesive bond according to SIST-TS-CEN/TS 13354:2004 standard. All of the examined adhesive mixtures for usage in dry conditions correspond to the standard. MUF100/LW0, MUF90/LW10 and MUF80/LW20 adhesive mixtures can just be used for humid and exterior conditions corresponding to the standard for usage of shuttering panels. The results show that we can replace a certain proportion of MUF adhesive with liquefied wood for manufacturing of shuttering panels, but we must adapt them according to the conditions of use.
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