Izdelava furnirne vezane plošče z različnimi mešanicami MUF lepila in utekočinjenega lesa : diplomsko delo - visokošolski strokovni študij

Poplaz, Janez (author), Šernek, Milan (mentor), Šega, Bogdan (reviewer)

V raziskavi smo proučevali vpliv temperature lepljenja in različnih lepilnih mešanic melamin-urea-formaldehidnega (MUF) lepila in utekočinjenega lesa (UL) na mehanske in fizikalne lastnosti 3-slojnih furnirnih vezanih plošč, ki so bile lepljene v klasični stiskalnici za vroče lepljenje. Uporabili smo 5 lepilnih mešanic z naslednjimi razmerji med MUF lepilom in UL: MUF100/UL0, MUF90/UL10, MUF80/UL20, MUF70/UL30 ter MUF60/UL40. V prvem delu smo uporabili enako temperaturo lepljenja (135 °C) za vse lepilne mešanice, v drugem delu pa smo izbrali lepilni mešanici MUF100/UL0 in MUF70/UL30 ter jih uporabili za izdelavo plošč pri različnih temperaturah lepljenja (155 °C, 165 °C, 175 °C). Iz izdelanih plošč smo nato pripravili preskušance za ugotavljanje strižne trdnosti lepilnega spoja in upogibne trdnosti ter modula elastičnosti furnirnih vezanih plošč. Po standardu SIST EN 314-2 so zahtevam za uporabo plošč v suhih pogojih ustrezale vse uporabljene lepilne mešanice pri vseh uporabljenih temperaturah lepljenja. Za uporabo v vlažnih pogojih so ustrezale lepilne mešanice z do 20 % dodanega UL, za uporabo v zunanjih pogojih pa lepilni mešanici z do 10 % dodanega UL. Lepilna mešanica ni bistveno vplivala na upogibne lastnosti izdelanih plošč.

• Language: Slovenian
• Keywords: furnirne plošče, utekočinjen les, melamin-urea-formaldehidno lepilo, klasično vroče stiskanje, strižna trdnost, upogibna trdnost
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: J. Poplaz
• Year: 2016
• Number of pages: IX, 48 f.
• PID: 20.500.12556/RUL-158779
• UDC: 630*824.8
• COBISS.SI-ID: 2657673
• Publication date in RUL: 20.06.2024

Secondary language

• Language: English
• Title: The manufacture of veneer plywood with different mixtures of MUF adhesives and liquefied wood : graduation thesis - higher professional studies

Abstract

In this study we investigated the influence of bonding temperatures and a variety of adhesive mixtures of melamine-urea-formaldehyde (MUF) adhesives and liquefied wood (LW) according tothe mechanical and physical properties of 3-layered veneer plywood panels, which were glued together by using the classic hot bonding press. We used 5 adhesive mixtures with the following proportions between the MUF adhesive and LW: MUF100 / LW0, MUF90 / LW10, MUF80 / LW20, MUF70 / LW30A and MUF60 / LW40. In the first part, we used the same gluing temperature (135 °C) for all the adhesive mixtures, while in the second part we selected adhesive mixtures MUF100 / LW0 and MUF70 / LW30, that we used for the manufacture of panels at different temperatures of bonding (155 °C, 165 °C, 175 °C). By using the manufactured panels special testers were prepared to determine the shear and flexible strength of adhesive bond. Moreover we also tested a module of elasticity of veneer plywood panels. According to standard EN 314-2, the requirements for the use of panels in dry conditions are suitable for all the adhesive mixtures at any temperatures of the bonding. For the use in humid conditions the adhesive mixtures with up to 20 % added LW are the only appropriate for the use. And the external conditions demand the adhesive mixtures with up to 10 % added LW as being suitable. However, the adhesive mixture does not significantly affect the bending properties of manufactured boards.

• Keywords: veneer plywood, liquefied wood, melamine-urea-formaldehyde (MUF) adhesives, classic press for the hot bonding, shear strength, bending strength