Wood glue

Wood glue is an adhesive used to tightly bond pieces of wood together. Many substances have been used as glues. Traditionally animal proteins like casein from milk or collagen from animal hides and bones were boiled down to make early glues. They worked by solidifying as they dried. Later, glues were made from plant starches like flour or potato starch. When combined with water and heated, the starch gelatinizes and forms a sticky paste as it dries. Plant-based glues were common for books and paper products, though they can break down more easily over time compared to animal-based glues.[1][2][3] Examples of modern wood glues include polyvinyl acetate (PVA) and epoxy resins. Some resins (i.e., glues) used in producing composite wood products may contain formaldehyde.[4] As of 2021, “the wood panel industry uses almost 95% of synthetic petroleum-derived thermosetting adhesives, mainly based on urea, phenol, and melamine, among others”.[5]

  1. ^ "A low-cost, formaldehyde-free, and high-performance starch-based wood adhesive :: BioResources". BioResources (in Kinyarwanda). 30 Apr 2018. Retrieved 12 Sep 2023.
  2. ^ Zhang, Yanhua; Ding, Longlong; Gu, Jiyou; Tan, Haiyan; Zhu, Libin (2015). "Preparation and properties of a starch-based wood adhesive with high bonding strength and water resistance". Carbohydrate Polymers. 115. Elsevier BV: 32–37. doi:10.1016/j.carbpol.2014.08.063. ISSN 0144-8617. PMID 25439864.
  3. ^ Maulana, Muhammad Iqbal; Lubis, Muhammad Adly Rahandi; Febrianto, Fauzi; Hua, Lee Seng; Iswanto, Apri Heri; Antov, Petar; et al. (2 Oct 2022). "Environmentally Friendly Starch-Based Adhesives for Bonding High-Performance Wood Composites: A Review". Forests. 13 (10). MDPI AG: 1614. doi:10.3390/f13101614. ISSN 1999-4907.
  4. ^ "Frequent Questions for Consumers about the Formaldehyde Standards for Composite Wood Products Act". US EPA. 26 Jul 2016. Retrieved 13 Sep 2023.
  5. ^ Raydan, Nidal Del Valle; Leroyer, Leo; Charrier, Bertrand; Robles, Eduardo (15 Dec 2021). "Recent Advances on the Development of Protein-Based Adhesives for Wood Composite Materials—A Review". Molecules. 26 (24). MDPI AG: 7617. doi:10.3390/molecules26247617. ISSN 1420-3049. PMC 8708089. PMID 34946693.