In industries such as coatings and chemical engineering, PU (Polyurethane) has always been a core material frequently mentioned, yet misunderstandings regarding its definition, principles, and applications have long persisted. In fact, PU is not a single resin or process, but a general term for materials based on specific chemical structures and reaction principles. Its unique performance advantages have enabled it to achieve widespread applications in multiple fields.
      From a chemical perspective, the name PU is derived from the combination of "Poly" (polymerization) and "Urethane". Its core structure is a polymer system composed of urethane linkages (–NH–CO–O–), which mostly exist in the form of three-dimensional cross-linked networks in coatings. The essential principle of its synthesis is the reaction between isocyanates (–NCO) and active hydrogen (–OH/–NH), a underlying logic that determines the basic properties of PU materials. In application scenarios, two-component PU coatings form highly stable paint films through the cross-linking reaction between hydroxyl resins in the base paint and isocyanates in the curing agent, while PU resins complete the reaction between polyols and polyisocyanates during the synthesis stage.
      It is worth noting that PU materials are not limited to oil-based systems. Water-based PU follows the same chemical essence, with differences only in the reaction timing, molecular existence form, and the state of NCO groups. In addition, PUA (Polyurethane Acrylate), which is often confused with PU, is actually a combination of a PU backbone and acrylic unsaturated end groups. Its curing relies on free radical polymerization initiated by UV light, which is completely different from the reaction principle of traditional PU.
      Today, relying on advantages such as high chemical resistance and high mechanical strength, PU materials have been widely used in coatings, building materials, light industry and other fields. The development of water-based PU is more in line with the environmental protection trend, and the market potential continues to release. With technological iteration, the application boundaries of PU materials are constantly expanding, providing important support for the innovative development of related industries.

      For more information, you can click: https://www.tiktok.com/@mia_iot