Polyurethane adhesives are a type of adhesive with polyurethane as the main component. With their unique molecular structure and performance, they play an indispensable role in many industrial fields and daily life. Its core functions are mainly reflected in the following aspects:
1. Its most prominent features are outstanding bonding performance and wide material adaptability. The polyurethane molecular chain contains polar carbamate groups and other groups, which can form strong physical adsorption and chemical bonding with the surfaces of various materials. Therefore, it can effectively bond a variety of the same or different materials such as metal, wood, glass, plastic (especially difficult-to-bond materials like PVC, PET, and TPU), rubber, fabric, leather, and ceramics, and is thus hailed as the "all-purpose adhesive".
2. Excellent flexibility and fatigue resistance. After the
Polyurethane Adhesive is cured, its molecular chain segments have both rigid and flexible segments, which endows the adhesive layer with certain strength as well as good elasticity, toughness and impact resistance. This characteristic enables it to perform exceptionally well when bonding components subjected to vibration, shock or thermal expansion and contraction, effectively buffering stress and preventing brittle cracking. It is widely used in fields such as automobiles, shoe materials, and textile composites.
3. Good low-temperature resistance and adjustability. Many polyurethane adhesives can still maintain good flexibility and bonding strength in low-temperature environments and are not prone to brittleness, which is superior to many other types of adhesives. Meanwhile, by adjusting the raw material ratio and formula, the curing speed, viscosity, initial adhesion, final strength, hardness, heat resistance (usually within the temperature range of -40℃ to over 100℃), and curing method (moisture curing, thermal curing, two-component reaction curing, etc.) can be flexibly designed to meet specific requirements.
4. It also features excellent wear resistance, oil resistance and solvent resistance, as well as the ability to penetrate and fill porous substrates. These functions make it have important applications in high-end manufacturing such as packaging, composite films, wood processing, rail transit, electronic and electrical packaging, and even aerospace.
The core function of polyurethane adhesives lies in their multi-faceted characteristics: powerful universal bonding ability, outstanding flexibility and shock resistance, wide temperature tolerance, and highly adjustable process performance, thus solving many complex and demanding bonding problems.
