Synthesis of P-/Si-containing (bio-) polyols and tailored catalytic nanofillers: Towards improving flame retardancy and smoke/toxicity suppression of flexible PU foams

• Applicant: Privatdozent Dr. Bernhard Schartel
• Subject Area: Polymer Materials ; Plastics Engineering
• Term: from 2018 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 392201417

In the case of fire the high thermal inertia of flexible polyurethane foam (FPUF) resulted in rapid heating of the top layer reducing time to ignition and speeding up flame spread, and thus limiting the application of FPUF in many fields. Further, burning PU releases a large amount of toxic gases such as CO, HCN, and NOx that cause human fatalities. The aim of this project is to propose novel flame retardant solutions that tackle both the reduction of heat release as well as the suppression of smoke and toxic volatiles. Flame-retarded polyols, bio-based or P-/Si-containing, and catalytic synergist consisting of a nanoparticle carrying catalytic sites, e.g. layered nanoparticle as support for metal oxides, will be synthesized, prepared and combined in FPUF. The catalytic sites are proposed to enhance charring as well as catalyse the oxidation of toxic products. The hybrid structures of nanoparticle and catalytic sites enhance the dispersion and effectivity. A comprehensive and multimethodical approach to investigate the pyrolysis, flammability, fire behaviour, fire residue, smoke generation and the release of toxic gasses will deliver a matchless deep insight. The flame retardancy modes of action will be identified, and the molecular mechanisms enhancing charring, suppressing smoke, and reducing toxic products are addressed as well. Proposing the decomposition pathways and the interactions between flame retardant, PU, and synergists are major goals of this project as well as getting an idea what mechanisms suppress smoke and reduce toxicity. The comparison of systematically varied PFUF will indicate the structure property relationships. Advanced methods will be used to support the interpretations and conclusions. The results will deliver guidelines for future development of flame retarded PFUF. Apart from the scientific objectives this project crucially stimulates the mobility of the involved researchers. Five months guest stays in the working groups will enable the scientific project employee to get a comprehensive knowledge on synthesis of flame retardants and functional nanoparticle, preparation of foam, and investigating the fire properties, and will promote the international education as well.

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: National Natural Science Foundation of China
• Cooperation Partner: Professor Yuan Hu