Silicone Surfactants for Balancing Physical Properties versus Flammability Performance in Rigid PUR Foam for Construction Applications

摘要

One of the most important performance attributes of a silicone surfactant used in rigid polyurethane (PUR) foam for construction applications is its impact on the foam flammability. Even though the surfactant is typically used at only 1% by weight in the formulation, the structure of the surfactant can directly affect the flame spread, flame height, mass retention, and smoke generation measured in various flammability standards. Furthermore, it is well known that the silicone surfactant structure heavily influences the physical properties of PUR foam such as foam density, surface voiding, and insulation value. We have conducted a multi-year fundamentals program to study the relationships between the surfactant structure versus the resulting PUR foam physical properties and flammability performance. This paper will present some of the results from this study, as well as describe how we have used these results to design new rigid PUR surfactants that can be balanced for flow, insulation properties, and flammability/smoke reduction.