Emulsion Polymer Isocyanates as Wood Adhesive: A Review

Grøstad, Kristin; Pedersen, Anders Tegtmeier

doi:10.1163/016942410x500981

Cited by 51 publications

(24 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Polymeric methylene bisphenyl diisocyanate (PMDI) was used as a cross-linker. PMDI is a polyisocyanate, which is widely used as a cross-linker for aqueous polymer-isocyanate (API) wood adhesive (Hori et al 2008;Grøstad and Pedersen 2010). PMDI contains multiple isocyano groups, which react with the free amino and hydroxyl groups of whey protein to cross-link protein molecules.…”

Section: Whey Protein-based Wood Adhesivementioning

confidence: 99%

Whey protein polymerisation and its applications in environmentally safe adhesives

Guo

Wang

2016

Int J of Dairy Tech

View full text Add to dashboard Cite

Whey protein is a group of globular proteins from cheese whey. It is a safe, degradable, renewable and abundant natural material compared with synthetic polymers. Native whey proteins do not exhibit good adhesive properties due to their low molecular weights and compact globular structures; however, under thermal treatment, these globular structures can be unfolded to form polymers or aggregates through intermolecular disulphide bonds via a thiol–disulphide interchange. Heat‐induced whey protein polymer exhibits good adhesive properties. With the addition of a cross‐linker, stabiliser or co‐binder, different types of wood and paper adhesives can be formulated using polymerised whey protein.

show abstract

Section: Whey Protein-based Wood Adhesivementioning

confidence: 99%

Whey protein polymerisation and its applications in environmentally safe adhesives

Guo

Wang

2016

Int J of Dairy Tech

View full text Add to dashboard Cite

show abstract

“…After 4 h, a similar decrease was appeared in 3% and 4% pMDI modified SM/EP adhesives. The pot life of adhesive can be determined as the time after blending modifier with adhesive when the adhesive no longer gives the required bond strength . Therefore, results suggested that only the SM/EP/2%pMDI adhesive can reach an acceptable pot life of 4 h, which met the requirement of commercial application.…”

Section: Resultsmentioning

confidence: 99%

Effects of polyisocyanate on properties and pot life of epoxy resin cross‐linked soybean meal‐based bioadhesive

Luo

et al. 2016

J of Applied Polymer Sci

View full text Add to dashboard Cite

In this study, polyisocyanate (pMDI) was introduced into epoxy resin modified soybean meal-based bioadhesive to address the issue of low dry bond strength. Specifically, we investigated the effects of adding pMDI in terms of amount and storage time on dry bond strength, water resistance, and pot life of adhesive. Factors examined included shear strength, apparent viscosity, chemical reaction, crystallinity, and morphology of modified adhesives. Results indicated that the dry bond strength and water resistance of the resultant plywood was respectively improved 29.5% and 39.7% by adding 2% pMDI. In addition, the pot life of modified adhesive reached in 4 h. Results also shown that the cross-linking reactions between epoxy group and carbonyl as well as isocyano and amino increased the cross-linking density and formed a denser cross-linking network structure of cured adhesive. The composite cross-linked soybean mealbased adhesive is environmental-friendly and high-performance, which will promote the industrial application of the soy protein-based adhesives.

show abstract

“…Similar to PUR, also EPI is a very moisture-resistant adhesive, curing via polyaddition and solvent displacement with characteristics of both, thermosetting and thermoplastic polymers. The system consists of a water-based emulsion, usually polyvinyl alcohol (PVA) that is derived by hydrolysis of polyvinyl acetate (PVAc) and is cured with an isocyanate cross-linker with one or more -NCO groups (Grøstad and Pedersen 2010). During gluing, different reactions and processes may take place, such as the water transport from the glue line to the wood adherend and reaction of NCO groups with water, other NCO groups, OH groups in PVA, functional groups and eventually to some degree with the hydroxyl groups of the wood adherend (Grøstad and Pedersen 2010;Qiao et al 2000).…”

Section: Interaction Of Adhesive System and Woodmentioning

confidence: 99%

“…The solid content usually is above 50% and varies depending on the implemented additives. Similar to PUR, also for EPI a couple of different additives are available to modify the later properties of the polymer and to increase the solid content (Grøstad and Pedersen 2010). The adhesive usually reaches its full mechanical strength and moisture resistance after 1-2 days of curing.…”

Section: Interaction Of Adhesive System and Woodmentioning

confidence: 99%

Adhesive-related warping of thin wooden bi-layers

et al. 2019

View full text Add to dashboard Cite

Warping of layered wood-based panels is still a challenging problem in the development of thin engineered wood products. Wood as an anisotropic and hydrophilic material tends to change its volume and mechanical properties with changing moisture content. Besides the wood components, also the mechanical properties of certain adhesives are sensitive to moisture changes. A moisture load onto the adhered wood is resulting in different stress and strain states between the adherends. It is expected that adhesives with different moisture-related properties participate differently to this interaction. To observe an adhesive-related warping, thin spruce/HDF (Picea abies and high-density fibreboard) bi-layers with identical material geometries were manufactured under laboratory conditions, using different wood adhesive systems, which are currently used in furniture and flooring industry [polyurethane (PUR), emulsion polymer isocyanate (EPI), polyvinyl acetate (PVAc), urea formaldehyde (UF) and ultra-low emitting formaldehyde amino adhesive (ULEF)]. The bi-layers were exposed to certain relative humidity conditions, and the resulting deformation was measured with a high-precision laser distance detector. Moisturedependent warping of the bi-layers was obtained in relation to the used adhesive systems. As a result of the study, it can be shown that initial warping after panel manufacturing strongly depends on the adhesive curing characteristics and, especially, on the amount of water that is released into the wood adherend. For the post-setting panel warping, a differentiation into two adhesive groups became visible: rigid and flexible adhesives. Rigid adhesives (UF and ULEF) showed a higher degree of warping compared to the group of flexible adhesives (PUR, EPI and PVAc).

show abstract

Emulsion Polymer Isocyanates as Wood Adhesive: A Review

Cited by 51 publications

References 6 publications

Whey protein polymerisation and its applications in environmentally safe adhesives

Whey protein polymerisation and its applications in environmentally safe adhesives

Effects of polyisocyanate on properties and pot life of epoxy resin cross‐linked soybean meal‐based bioadhesive

Adhesive-related warping of thin wooden bi-layers

Contact Info

Product

Resources

About