Untersuchungen zum Einfluss von Temperatur und Holzfeuchte auf das Versagensverhalten von ausgewählten Klebstoffen bei Zugscherbeanspruchung

Abstract

Studies on the influence of temperature and timber moisture on the failure behaviour of selected adhesives under tensile shear load. The influence of temperature and relative humidity on shear strength was tested in a tensile shear test with three different adhesives. Two standard adhesives (PVAc, urea resin) and a 1KPUR (one-component polyurethane adhesive) produced in the laboratory were tested at a high temperature along with relative humidity. In addition distortion around the glue joint was measured by means of video image correlation and a shear modulus of the glue joint calculated from this.

Influence of ply configuration and adhesive type on cross-laminated timber in flexure at elevated temperatures

“…emissions of hazardous gases), and its influence on the fire safety of a timber building is only recently being recognised from a fire dynamics perspective to minimise the occurrence of char fall off in a fire [2,3]. While it is recognised that different adhesive types display varying performance when heated or subjected to changing moisture levels [4][5][6], the influence of adhesives on the structural capacity of CLT in fire is not currently considered in design and is not well understood.…”

Mistletoe viscin: a hygro- and mechano-responsive cellulose-based adhesive for diverse material applications

“…The natural substrate of the viscin adhesive is the tree bark covering the branches of host species ( 14 , 15 ); however, we demonstrated that viscin is essentially indiscriminate in terms of what surface chemistry it adheres to, showing adhesion to both biogenic materials such as wood, skin, and cartilage, as well as completely synthetic materials including various plastics, metal alloys, and glass. The adhesive strength measured from lap shear tests of viscin on wood under dry conditions (>2 MPa) are at least 3 times lower than those reported for standard synthetic wood glues based on polyvinyl acetate (PVA) and polyurethane, although reported values vary between studies ( 33 , 34 ). However, unlike PVA and polyurethane glues, which are primarily petroleum-sourced and slow to degrade ( 35 ), mistletoe viscin is comprised of biorenewable and biodegradable molecular components.…”

Isıl İşlem Görmüş Ahşap Kullanılarak Çeşitli Koşullar Altında Yapışma Performansının İncelenmesi

“…This reduced the bond strength due to the difference in moisture and its effect on the shear stress of the wood. Due to the heat treatment of the glue layer, the bonding strength of A1-normal material components has decreased [5,34,35,36,10,11]. The adhesion strength values of heat-treated wood samples obtained under A5 holding conditions were slightly higher than the untreated samples.…”