This MSc thesis examines the physical and mechanical properties of particleboard bonded with melamine-urea formaldehyde adhesive (MUF) and nanofibrillated cellulose (NFC) mixture in different mass ratios. Initial investigation was related to the impact of NFC share on viscosity and gel time. The viscosity increased with increasing NFC share, while gel time was not affected by NFC share. Single-layer fibreboard and particleboards with different quantities of NFC (0-3%) and threelayer particleboards with NFC were produced, where NFC was added either in surface (0-5%) or in core layer (0-3%). The various physical (density, thickness, moisture content, thermal conductivity, thickness swelling after immersion into water) and mechanical properties (bending and tensile strength, internal bond, surface soundness and compressive-shear strength) were determined. At singlelayer boards and the threelayer particleboards, where NFC was added to surface layer, an improvement of mechanical properties was observed, as well as a greater resistance against exposure to water. The addition of NFC to core layer of threelayer particleboard resulted in negative impact on mentioned properties. No significant changes in thermal conductivity and formaldehyde emission were observed.
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