Processing and Upscaling of Fire-Resistant Nano-Filled Thermosetting Polyester Resin The Polyfire Project Project Aims: • Develop and scale-up fire-retardant polyester-nanoclay resin systems and processing techniques • Eliminate halogenated fire-retardant additives • Reduce weight and cost • Improve safety in a number of fire-critical sectors including construction and marine Key Facts: • A collaborative European project, funded by the European Commission 7 th Framework Programme. •11 partners from 5 countries (5 SMEs, 3 research institutes, 2 large companies, 1 association) •3 years (1 September 2009 – 31 August 2012) The Challenges • To achieve good fire performance, the clay must be correctly dispersed in the resin • Evidence suggests that an intercalated structure is preferable for fire-retardant properties, because these ideally require the clay platelets to be in parallel to create a consistent barrier • Organomodification of the clay surface is required in order to increase platelet-platelet separation and increase compatibility with the UP resin • Polymer molecules can then enter the clay gallery and start to overcome the inter- layer attractive forces • Mechanical mixing is then needed, to provide the required level of dispersion • The Polyfire project will develop and optimise both the organomodification and mixing processes. • Both processes will be scaled-up to demonstrate industrial production feasibility. This project has received funding from the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement n° 229220. www.polyfireproject.eu Industrial Interest Group Organisations interested in the Polyfire project are invited to join our Industrial Interest Group: • Exchange the scientific and technological information necessary for the successful direction of the project and the achievement of its objectives • Cooperate with industrial researchers and technologists regarding the innovative concepts developed • Keep informed on the progress of the Polyfire project For More Information Case Studies • At least three demonstration composite panels will be produced and tested to showcase the materials and process developed in the Polyfire project. • The parts selected to date are a passenger ferry balcony floor, a train interior panel and a passenger lift wall panel. Balcony of Passenger Ferry Train Interior Panel Passenger Lift Wall Panel Background Unsaturated Polyester Resins • Extensive use in fibre-reinforced composites and coatings • Low cost, good processability and balance of properties • But, burn vigorously and generate dense smoke • Fire performance improved by using fire-retardant additives Fire Retardant Additives • Halogenated compounds, antimony-based systems and non-combustible fillers (such as aluminium trihydrate, ATH) are the most common • Halogentated systems can generate large quantities of toxic and corrosive combustion products, so tend to perform poorly in more modern fire tests • The growing trend is towards halogen-free additives, such as ATH or ammonium polyphosphate (APP) • But these must be used at high loading to achieve the desired fire performance • Processability, strength and impact resistance are all reduced and weight is increased Clay as a Fire Retardant • Addition of small amounts of well-dispersed, nano-sized particles can result in simultaneous improvement in a range of mechanical and physical properties, including fire retardancy • The improvement in fire retardancy is attributed to the formation of a continuous, defect-free char • The char forms a barrier on the surface, protecting the un- burnt polymer beneath • Synergistic interactions between nano-dispersed clay, resin and traditional fire- retardant additives have been identified • Previous studies have produced a halogen-free, nanoclay ‘filled’ unsaturated polyester resin (UP NC) which passed UL94-V0 • Cone calorimeter tests showed similar performance to BS476 pt7 class 2 halogenated system • Achieved equivalent performance to halogenated UP resin with 20-25% cost reduction Comparison of Heat Release Rate for clay- filled unsaturated polyester (UP NC) and unfilled unsaturated polyester (UP). FEG-ESEM showing the clay/carbon char layer on the surface of Nylon 6,6 polymer. Char Layer Polyme r Dr Ben Hargreaves NetComposites Ltd 4A Broom Business Park, Bridge Way Chesterfield S41 9QG, UK Phone: +44(0)1246 266244 Fax: +44(0)1246 266249 email: [email protected] Web: www.polyfireproject.eu Polymer “Traditional” phase- separated microcomposit e Ordered intercalated nanocomposite Disordered exfoliated nanocomposite Cationic Surfacta nt Clay Layer