Razvoj trdnosti polivinilacetatnega lepilnega spoja pri lepljenju furnirja

Šauperl, Toni (author), Šernek, Milan (mentor)

Proučevali smo razvoj trdnosti polivinilacetatnega (PVAc) lepilnega spoja pri lepljenju furnirja. Preizkušanci so bili standardnih dimenzij iz bukovega (Fagus sylvatica L.) furnirja debeline 0,84 mm. Klimatizirani so bili pri sobnih pogojih: 25 °C in 50 % vlažnosti. Uporabili smo dve vrsti PVAc lepil proizvajalca Mitol: Mekol D3 in Mekol SPECIAL, ki sta bili že vnaprej pripravljeni. Graditev strižne trdnosti PVAc lepilnega spoja med vročim stiskanjem smo ugotavljali s pomočjo ABES (Automated Bonding Evaluation System) instrumenta. Temperatura stiskanja je bila konstantna in je znašala 80 °C, čas stiskanja smo za posamezno meritev spreminjali in je bil v razponu od 30 do 300 s v intervalu 30 s. Proučevali smo tudi vpliv 5 s in 30 s hlajenja po vročem stiskanju na končno trdnost lepilnega spoja. Rast temperature v lepilnem spoju smo spremljali s termočlenom. Ugotovili smo, da je strižna trdnost PVAc lepilnih spojev naraščala s časom stiskanja in po določenem času dosegla maksimalno vrednost. Vrsta PVAc lepila ni bistveno vplivala na končno trdnost ohlajenega lepilnega spoja, medtem ko je pri vroče testiranih spojih bila razlika v trdnosti. Ugotovili smo, da so preizkušanci pod vplivom hlajenja dosegali bistveno višje trdnosti lepilnega spoja, kot vroče testirani. Najvišjo strižno trdnost lepilnega spoja smo dosegli z lepilom Mekol D3 pod 30 s vplivom hlajenja in je znašala 8,69 N/mm2.

• Language: Slovenian
• Keywords: furnir, lepilni spoj, PVAc, strižna trdnost, vpliv temperature
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [T. Šauperl]
• Year: 2020
• PID: 20.500.12556/RUL-119927
• UDC: 630*824.839
• COBISS.SI-ID: 28384515
• Publication date in RUL: 13.09.2020

Secondary language

• Language: English
• Title: Development of polyvinyl acetate adhesive bond at gluing of veneer

Abstract

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.

• Keywords: veneer, adhesive bond, PVAc, shear strength, influence of temperature