Uporaba visokofrekvenčne tehnologije za lepljenje furnirnih vezanih plošč z mešanicami utekočinjenega lesa in MUF lepila : diplomsko delo - visokošolski strokovni študij

Veberič, Rok (author), Šernek, Milan (mentor), Šega, Bogdan (comentor), Medved, Sergej (reviewer)

Proučevali smo mehanske in fizikalne lastnosti furnirnih bukovih vezanih plošč, ki so bile z visokofrekvenčno tehnologijo (VF) zlepljene z različnimi mešanicami melamin-urea-formaldehidnega (MUF) lepila in utekočinjenega lesa (UL). Iskali smo primerno mešanico MUF in UL, ki še ustreza standardu SIST EN 314-2:1996, kjer mora strižna trdnost spoja za izpolnjevanje zahtev dosegati večje ali enako vrednost 1 N/mm2. Pripravili smo 5 lepilnih mešanic z različnim deležem UL in MUF lepila. Uporabili smo razmerja: 100MUF+0UL, 90MUF+10UL, 80MUF+20UL, 70MUF+30UL in 60MUF+40UL. Iz pripravljenih 3-slojnih furnirnih vezanih plošč dimenzij 500 mm x 500 mm x 4,8 mm smo izžagali preskušance za ugotavljanje strižne trdnosti lepilnega spoja, upogibne trdnosti in modul elastičnosti ter za določitev gostote in vlažnosti zlepljenih plošč. Zahtevam standarda SIST EN 314-2 za uporabo v vlažnih in zunanjih pogojih so ustrezale plošče zlepljenje z mešanicami 100MUF+0UL, 90MUF+10UL in MUF80+UL20, torej z majhnim deležem UL (do 20 delov). Za lepljenje furnirnih plošč za uporabo v suhih pogojih pa so ustrezala vsa uporabljena razmerja med MUF in UL.

• Language: Slovenian
• Keywords: furnirne plošče, lepljenje, melamin-urea-formaldehid, utekočinjen les, visokofrekvenčna tehnologija
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [R. Veberič]
• Year: 2015
• Number of pages: IX, 43 f.
• PID: 20.500.12556/RUL-117693
• UDC: 630*832.281
• COBISS.SI-ID: 2388873
• Publication date in RUL: 22.07.2020

Secondary language

• Language: English
• Title: The use of high-frequency technology for bonding veneer plywood with mixtures od liquefied wood and MUF adhesives

Abstract

The focus of research was to determine the mechanical and physical properties of beech veneer panels of plywood, bound together with a melamine-urea-formaldehyde (MUF) resin. The adhesive mixture was infused with various proportions of liquefied wood (LW) and the primed sheets were pressed by means of high-frequency technology (HF). The main objective was to determine the most appropriate mix between MUF and liquefied wood that still corresponds to the standard SIST EN 314-2: 1996, where the shear strength of the joint to meet the requirements to achieve greater or equal to the value of 1 N / mm2. The research began with a so-called pre-test on a number of bound 3-layered veneer plywood panels. The pre-test was applied to determine the optimum pressing parameters. The main study featured the preparation of 5 adhesive mixtures with varying ratios between the MUF adhesive and liquefied wood (LW). The effects of following ratios were observed: 100MUF+0LW, 90MUF+10LW, 80MUF+20LW, 70MUF+30LW and 60MUF+40LW. The primed 3-layered veneer plywood panels (500 mm x 500 mm x 4,8 mm), were applied as surfaces from which test samples were cut. SIST EN 314-2 for use in humid and external conditions corresponded to panel adhesive mixtures 100MUF+0LW, 90MUF+10LW and 80MUF+20LW, therefore, with a small percentage LW (up to 20 parts). For use in dry conditions corresponds to any relationship between the MUF and LW.

• Keywords: veneer plywood, gluing, melamine-urea-formaldehyde, liquefied wood, high-frequency technology