Dimethylsiloxane, ethylene oxide block copolymer

Dimethylsiloxane ethylene oxide block copolymer (CAS 27306-78-1) is a silicone-polyether surfactant commercially known under trade names including Silwet L-77, L 77, N 380, and Pentra-Bark. It carries no assigned E-code and is classified under EC 608-078-3. The compound combines a polydimethylsiloxane backbone with polyethylene oxide side chains.

In agricultural formulations, it functions as a superspreader, reducing droplet contact angle on hydrophobic leaf surfaces to drive active ingredient penetration through stomata. In textile and coatings applications, it lowers interfacial tension between aqueous phases and substrate surfaces, enabling uniform film formation and improving wetting on low-energy materials such as polyolefins and treated fabrics.

This material is subject to REACH registration requirements for EU supply. It is available in liquid form across standard industrial packaging formats including drums and IBCs. Procurement teams should confirm grade specification and purity documentation directly with the supplier prior to ordering.