(769d) Environmentally Friendly Flame Retardants Based on Adhesive Catecholamine

There has been much effort expended over the last few decades to develop a wide variety of flame retardant (FR) additives for the purposes of preventing fire spread and reducing the risk of fire-related injuries from everyday-use materials such as polymers and textiles. Some of the most frequently used FR chemicals are halogenated and organophosphorous materials due to their cost-effectiveness and extensive industrial availability. However, there have been serious concerns raised regarding their impact to human health and the environment. This has spawned efforts in industry and academia to development replacement FR materials. In this presentation, we will describe a novel surface coating FR system based on a catecholamine derivative called polydopamine (pDA) that was applied to polyurethane (PU) foam in a single step [1, 2]. PU foam is a particularly attractive test material because it is highly flammable without FRs and it is one of the most widely-used polymers in our daily life. The dopamine precursor to pDA is a naturally occurring chemical found in our body and other living organisms, and this material has an ability to undergo self-polymerization into pDA under mild basic pH conditions. The conformal pDA coating was applied to PU during a simple aqueous dip coating procedure. The catechol functional group in pDA inherently gives this material a nearly universal surface adhesion capability and imparts radical scavenging capability, one of many important features of additives that serve as FRs. pDA coated PU foam exhibited a remarkably reduced flammability compared to pure PU foam and also self-extinguished in some cases. Data regarding the mechanism of flame retardancy of pDA, including morphological observation using scanning electron microscopy (SEM) and quantitative thermal analysis using micro combustion calorimetry, cone calorimetry and thermogravimetric analysis, will also be discussed. We believe this study introduces new opportunities for utilizing naturally derived materials for future green FR applications.

References:

[1] Bioinspired Catecholic Flame Retardant Nanocoating for Flexible Polyurethane Foams, J.H. Cho, V. Vasager, K. Shanmuganathan, S. Nazarenko, and C.J. Ellison, Chemistry of Materials, 27, 6784–6790, 2015.

http://pubs.acs.org/doi/10.1021/acs.chemmater.5b03013

[2] Development of Kinetic Parameters for Polyurethane Thermal Degradation Modeling Featuring a Bioinspired Catecholic Flame Retardant, B.C. Roberts, A.R. Jones, O.A. Ezekoye, C.J. Ellison, and M.E. Webber, Combustion and Flame, 177, 184-192, 2017.

http://www.sciencedirect.com/science/article/pii/S0010218016303777