Phosphorus-Containing Flame Retardant Resins

Fires can result in loss of life, material losses, and the destruction of unique artistic and historical artifacts. Rapid population growth, unplanned urbanization, and accelerated industrialization are increasing the number of fires and the extent of damage caused by them. One of the measures to be taken to minimize loss of life and property resulting from fires is the use of non-combustible chemicals. Fundamentally, these chemicals can be divided into two main groups: flame retardants and smoke suppression agents such as additives and reactants. Additives are typically used as fillers and, unlike reactive compounds, do not react with other components [1]. Generally, two important properties are expected from flame retardants. Flame retardants must have a flame-retarding effect and must not impair the processing properties of the base material to be incorporated later. Flame-retardant additives added in specific proportions dilute the easily flammable base material and reduce the oxygen index of the base material. The oxygen index is the minimum amount of oxygen required for the base material to continue burning [2,3]. The flame retardant market is growing at an annual rate of 5%. The most important reason for this is the increased use of plastics today. PCB (polychlorinated biphenyls), one of the first flame retardants, was banned in 1977 due to its toxic effects. Today, bromine-based flame retardants are used, but their use is limited due to side effects. Since 2008, the European Union has banned the use of many PDBEs (polybrominated diphenyl ethers). Problems related to flame retardants worldwide can be listed as the accumulation of inorganic substances in organisms, poisoning of people affected by these chemicals during fires, and the effects of undesirable gases resulting from combustion on the environment. The use of materials containing chlorine and bromine-based flame retardants has been periodically restricted or banned since 2000 due to the formation of gases harmful to the environment and humans as a result of combustion. The development of harmless flame-retardant polymeric materials has gained great importance in recent years due to rapid technological advances [4]. Flame-retardant polymers can be prepared by adding flame-retardant additives to polymers or by chemically bonding flame-retardant compounds to polymers. The use of flame-retardant additives requires high loading levels to achieve adequate flame retardancy, and while halogenated flame retardants can produce toxic and corrosive fumes during combustion, chemically bonded compounds can be effective in small amounts. Compared to halogenated flame retardants, phosphorus-containing compounds have been found to produce less toxic gas and smoke during combustion. Chemically added phosphorus-containing monomers enhance flame retardancy. Thus, phosphorus-containing monomers are widely used in flame-retardant coatings. Due to the toxicity and environmental concerns of halogenated flame retardants, phosphorus-containing flame retardants have attracted considerable attention as environmentally friendly alternatives [5]. Since flame retardants used as additives settle over time and their effects diminish, polymers with inherent non-flammability properties are preferred. Phosphorus-containing flame retardants are replacing halogenated flame retardants because they produce less toxic gas during combustion [6,7]. İzel Kimya is conducting research on the production of new resins with fire-retardant properties to create more durable coatings. Through chemical bonding, phosphorus-containing monomers can be added to different resins such as alkyd, acrylic, and polyester, and flame retardancy can then be enhanced in coatings derived from them.

References [1] Alexander B. Morgan (2019) The Future of Flame Retardant Polymers – Unmet Needs and Likely New Approaches, Polymer Reviews, 59:1, 25-54. [2] V. Babrauskas, R. Fuoco, A. Blum, Chapter 3- Flame Retardant Additives in Polymers: When do the Fire Safety Benefits Outweigh the Toxicity Risks? Editor(s): Constantine D. Papaspyrides, Pantelis Kiliaris, Polymer Green Flame Retardants, Elsevier,2014, 87-118. [3] Al-Mosawi, Ali & Abbas Abdulsada, Shaymaa. (2015). Flame Retardancy of Biopolymer Polyhydroxyalkanoate Composite. International Journal of Advanced Research.3. 883- 886. [4] Wang, Hui & Wang, Shuang & Du, Xiaosheng & Wang, Haibo & Cheng, Xu & Du, Zongliang. (2019). Synthesis of a novel flame retardant based on DOPO derivatives and its application in waterborne polyurethane. RSC Advances. 9. 7411-7419. [5] Emrah Çakmakçı, Yusuf Mülazim, Memet Vezir Kahraman, Nilhan Kayaman Apohan, Flame retardant thiol–ene photocured coatings, Reactive and Functional Polymers, Volume 71, Issue 1, 2011, 36-41, [6] Khalifah A. Salmeia, Sabyasachi Gaan, An overview of some recent advances in DOPO derivatives: Chemistry and flame-retardant applications, Polymer Degradation and Stability, Volume 113, 2015, 119-134. [7] Shuyu Liang, N. Matthias Neisius, Sabyasachi Gaan, Recent developments in flame retardant polymeric coatings, Progress in Organic Coatings, Volume 76, Issue 11, 2013, 1642-1665.

Dr. Cemil Dızman Research and Development Director İzel Kimya Elif Ozman Research and Development Researcher İzel Kimya