SUSTAINABLE FLAME RETARDANTS: BIO-DERIVED PRODUCTS AS INTUMESCING MATERIALS
Mauro Zammarano, Douglas M. Fox, Szabolcs Matko, Takashi Kashiwagi, Jeffrey W. Gilman, Rick D. Davis
Scientists are shifting their attention towards technology sustainability and sustainable materials, specifically in terms of energy and environmental impacts. The flame retardant community is also more concerned about these aspects. The recent banning of some brominated flame retardants in Europe and USA points out that environment impact in terms of persistency and bio-accumulation is becoming a key factor for public perception. Intumescent systems based on phosphorous compounds have been suggested as highly efficient alternative to halogenated flame retardants. Lately, not only halogen based flame retardants but also phosphorous based flame retardants are under scrutiny for their environmental and health safety (EHS) issues. It appears that there is a need for sustainable flame retardants with low EHS impact. In this work we show how natural derived products, like modified lignin, can be used for preparing sustainable intumescent systems with high efficiency. Lignin is the second most abundant organic substance on earth after cellulose and is increasingly available as by-product of cellulose production. Its price (20¢/lb) is significantly lower than commodity polymers, thus lignin is commonly used as polymer filler. Here, we show that modified lignin is also an effective flame retardant. Epoxy resin is used as a case study. The mass loss rate of the epoxy-lignin composites is investigated by means of gasification apparatus. Preliminary results show that lignin-based products produce a continuous protective char capable to protect the underlying polymer throughout the combustion process and, thus, decrease the heat release rate.
, Fox, D.
, Matko, S.
, Kashiwagi, T.
, Gilman, J.
and Davis, R.
SUSTAINABLE FLAME RETARDANTS: BIO-DERIVED PRODUCTS AS INTUMESCING MATERIALS, Fire and Materials 2011, San Francisco, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=907505
(Accessed March 4, 2024)