{"id":11478,"date":"2025-08-06T09:55:29","date_gmt":"2025-08-06T06:25:29","guid":{"rendered":"https:\/\/ajbaspar.com\/%d9%85%d8%b9%d8%b1%d9%81%db%8c-%da%86%d8%b3%d8%a8-%d9%87%d8%a7%db%8c-%d9%be%d9%84%db%8c-%db%8c%d9%88%d8%b1%d8%aa%d8%a7%d9%86\/"},"modified":"2025-08-06T10:19:31","modified_gmt":"2025-08-06T06:49:31","slug":"what-is-polyurethane-adhesive","status":"publish","type":"post","link":"https:\/\/ajbaspar.com\/en\/what-is-polyurethane-adhesive\/","title":{"rendered":"What is polyurethane adhesive"},"content":{"rendered":"

What is polyurethane adhesive<\/strong><\/span><\/h1>\n

Introduction to Water-Based Polyurethane Adhesives<\/strong><\/span><\/h2>\n

Polyurethanes (PUs) are a diverse class of polymer materials that can be used in various adhesives and coatings. These materials have gained significant attention due to their strong bonding capability, durability, and high peel strength. PU-based adhesives exhibit excellent resistance to temperature and humidity variations.<\/span>
\nIn the following sections, we\u2019ll explore the diverse properties of these adhesives, along with their advantages and limitations for use in different fields<\/span><\/p>\n

Advantages and limitations of Polyurethane Adhesives<\/strong><\/span><\/h3>\n\n\n\n\n
advantages<\/strong><\/span><\/td>\nlimitations<\/strong><\/span><\/td>\n<\/tr>\n
\n

High Strength and Durability\u00a0\u00a0<\/span><\/strong><\/p>\n

Variable Curing Time<\/strong><\/span><\/p>\n

High Flexibility at Low Temperatures<\/strong><\/span><\/p>\n

Excellent Solvent Resistance Wear and Corrosion Resistance<\/strong><\/span><\/td>\n

\n

Primer Requirement<\/strong><\/span><\/p>\n

Low Heat Resistance<\/strong><\/span><\/p>\n

Limited Shelf Life<\/strong><\/span><\/p>\n

If there is an empty spot on the surface without adhesive, the bonding strength can be compromised<\/strong><\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Types of Polyurethane Adhesives<\/span><\/h3>\n

Polyurethane adhesives come in various forms. There are one-component and two-component adhesives, both based on similar chemical principles. Additionally, there are hot melt adhesives. Each type has its advantages, disadvantages, and diverse applications.<\/span><\/p>\n\n\n\n\n\n\n\n\n\n
industry<\/span><\/td>\nDescription<\/span><\/td>\n<\/tr>\n
Wood<\/span><\/p>\n

 <\/p>\n

 <\/td>\n

Polyurethane adhesives used in the wood industry, such as bonding wood to wood, PVC to wood, and wood veneering, must possess at least one of the following high-performance features: durability, transparency, and resistance to heat and moisture<\/span><\/td>\n<\/tr>\n
shoes<\/span><\/td>\nThe shoe industry is one of the sectors where final products are exposed to various weather conditions, making their usage quite challenging. Additionally, the materials used in shoe production are highly diverse. Therefore, the adhesive required in this industry must have exceptional durability to withstand tough usage conditions.<\/span><\/td>\n<\/tr>\n
transportation<\/span><\/td>\nPolyurethane adhesives offer a suitable solution for the ever-increasing demands and constraints of the transportation industry.\u00a0These adhesives provide exceptionally strong and durable bonds on various surfaces, even in challenging weather conditions (high temperatures, humidity, exposure to cleaning agents, and different chemicals)<\/span><\/td>\n<\/tr>\n
Sealants<\/span><\/td>\nPolyurethane sealants are used for protecting glass, sanitary sealants, and automotive applications.\u00a0They are required to withstand tough conditions, exhibit excellent adhesion to various surfaces, and resist chemicals and moisture<\/span><\/td>\n<\/tr>\n
Non-Woven Textiles<\/strong><\/span><\/td>\nDue to their exceptional bonding properties on various surfaces, polyurethane adhesives allow the formulation of adhesives with outstanding adhesion for non-woven textiles<\/span><\/td>\n<\/tr>\n
Flexible packaging<\/span><\/td>\n\n

Polyurethane adhesives used in flexible packaging demonstrate good adhesion to various surfaces, including plastic films, aluminum, and paperboard. These adhesives are particularly suitable for applications where heat and moisture resistance, transparency, and resistance to yellowing are required.<\/span><\/p>\n

Furthermore, when using these adhesives, there is no release of toxic amines into the environment.<\/span><\/p>\n

\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Polyurethane Adhesives are typically two-component systems that chemically bond two surfaces together. These systems consist of a resin component (the adhesive) and a hardener component. Both components must be mixed in specific proportions. The exact ratios vary depending on the specific adhesive formulation.<\/span>
\nWater-based polyurethane adhesives are divided into different hardness grades. They are designed to withstand high tensile forces and require excellent tensile strength. Additionally, they exhibit high resistance to weathering and maintain their adhesive properties over time due to their cohesive structure.<\/span>
\nThe chemical combination of these adhesives involves a reaction between a polyisocyanate component and a polyol component. This reaction forms a strong network within the adhesive. Water-based polyurethane adhesives can easily cure at room temperature and are commonly used in situations where surfaces are sensitive to heat or are too large for heat application<\/span><\/p>\n

\u00a0One-component polyurethane adhesives<\/strong><\/span><\/h3>\n

These adhesives are composed of a single component. Initially, they form a film and have a rapid curing process. Once dried, they maintain their elastic properties. The formulation of these materials involves blocking diisocyanatos, which are released upon application and heat for curing. This reaction creates a strong polyurethane network, ultimately resulting in adhesive properties .<\/span>
\nHotmelt Adhesives are typically composed of thermoplastic polymers. This means that these adhesives melt upon heating and can be used in their molten state. As the temperature decreases, they solidify and adhere to surfaces. Unlike one-component and two-component adhesives, hotmelt adhesives do not require surface porosity for bonding because their adhesion reaction is not chemical in nature. Instead, they adhere when they dry and undergo a physical change.<\/span>
\nExisting standards for the use of polyurethane adhesives are as follows:<\/span>
\nIn some applications of polyurethane adhesives, such as sports adhesives and cabinet door lamination, the adhesives are exposed to unfavorable temperature and humidity conditions. Therefore, the following categories are used to standardize these adhesives.<\/span><\/p>\n\n\n\n\n\n\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D1<\/span><\/td>\nAdhesives that are resistant to a minimum pressure force of\u00a010 MPa<\/strong>\u00a0in dry weather conditions<\/span><\/td>\n<\/tr>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D2<\/span><\/td>\nAdhesives that are initially submerged in water at\u00a020\u00b0C<\/strong>\u00a0for\u00a03 hours<\/strong>, then dried, and must withstand a minimum force of\u00a08 MPa<\/strong><\/span><\/td>\n<\/tr>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D3<\/span><\/td>\nAdhesives used for external building doors and windows must undergo a\u00a04-day immersion<\/strong>\u00a0in water. Before immersion, they should withstand a minimum force of\u00a010 MPa<\/strong>, and in a wet state, a minimum force of\u00a02 MPa<\/strong>. After drying, they should maintain a minimum force resistance of\u00a08 MPa<\/strong><\/span><\/td>\n<\/tr>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D4<\/span><\/td>\nAdhesives that even under very harsh conditions exhibit high resistance, such as adhesives used in sanitary equipment, shipbuilding, and building facades. These adhesives must be immersed in boiling water for 6 hours and then dried. In this regard, these adhesives should withstand a minimum force of\u00a010 MPa<\/strong>\u00a0in the initial state, a minimum force of\u00a04 MPa<\/strong>\u00a0in wet conditions, and a force of\u00a08 MPa<\/strong>\u00a0after drying<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n
<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

What is polyurethane adhesive Introduction to Water-Based Polyurethane Adhesives Polyurethanes (PUs) are a diverse class of polymer materials that can be used … Read more<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":11479,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[257,107,106,108],"tags":[],"class_list":["post-11478","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog-en","category-resin","category-vacuum-membrane","category-water-based-polyurethane"],"_links":{"self":[{"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/posts\/11478","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/comments?post=11478"}],"version-history":[{"count":9,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/posts\/11478\/revisions"}],"predecessor-version":[{"id":11488,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/posts\/11478\/revisions\/11488"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/media\/11479"}],"wp:attachment":[{"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/media?parent=11478"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/categories?post=11478"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ajbaspar.com\/en\/wp-json\/wp\/v2\/tags?post=11478"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}