This strong adhesion mainly stems from the polar groups in the water-based polyurethane structure, such as urethane bonds, urea bonds, and ionic bonds. These groups interact with the fabric surface through Coulomb forces, van der Waals forces, and hydrogen bonds. The ideal bonding state is when the adhesion between the coating agent and the fabric is greater than the cohesive force of the fabric itself, but less than the cohesive force between the coating agent molecules. The density of the film is directly related to the cohesive energy of the water-based polyurethane molecules: the greater the cohesive energy, the smaller the distance between molecules, and the more compact the resulting film structure. In addition, to achieve better waterproofing effects, the surface tension of the water-based polyurethane film is reduced as much as possible, which increases the contact angle of water droplets on the film, making them less likely to spread out, thus effectively reducing the penetration of water into the coating.

Sinograce Chemical produces water-based polyurethane resins for textile applications, including polyurethane waterproof coatings and polyurethane textile resins.  Inquiries are welcome.

Room 1013, Building A5, Financial Port Center, Yangzijiang Road, Baohe District, Hefei City， Anhui province, China

+86 0551 63459511

sales@sinogracechem.com

vivisinograce@outlook.com

+8615755193346

http://www.sinogracechem.com