--- title: "Flame Retardancy in Epoxy: The TDPPI Breakthrough" id: "2935" type: "post" slug: "flame-retardancy-in-epoxy-the-tdppi-breakthrough" published_at: "2023-12-16T17:16:37+00:00" modified_at: "2023-12-16T18:39:37+00:00" url: "https://www.plasticsengineering.org/2023/12/flame-retardancy-in-epoxy-the-tdppi-breakthrough-002935/" markdown_url: "https://www.plasticsengineering.org/2023/12/flame-retardancy-in-epoxy-the-tdppi-breakthrough-002935.md" excerpt: "A groundbreaking flame retardant has emerged to redefine the performance of epoxy composites. Meet tris[4-(2,5-dioxopyrrol-1-yl)phenyl] phosphite (TDPPI), a phosphorus-based maleimide boasting unparalleled attributes such as moderate transparency, enhanced thermal stability, and improved mechanical strength." taxonomy_category: - "Additives & Colorants" - "Automotive & Transportation" - "Building & Construction" - "Editor's Choice Technical Paper" - "Industry" - "Materials" - "Resins" - "Thermosets" - "Trending" taxonomy_post_tag: - "Epoxy" - "epoxy composites" - "Flame-Retardant" - "TDPPI" --- [Home](https://www.plasticsengineering.org/) » [News](https://www.plasticsengineering.org/news/) » [Trending](https://www.plasticsengineering.org/c/trending/) » [Editor's Choice Technical Paper](https://www.plasticsengineering.org/c/trending/editors-choice-technical-paper/) » Flame Retardancy in Epoxy: The TDPPI Breakthrough # Flame Retardancy in Epoxy: The TDPPI Breakthrough DSC trace of neat epoxy and epoxy-TDPPI compositesA groundbreaking flame retardant has emerged to redefine the performance of epoxy composites. Meet tris[4-(2,5-dioxopyrrol-1-yl)phenyl] phosphite (TDPPI), a phosphorus-based maleimide boasting unparalleled attributes such as moderate transparency, enhanced thermal stability, and improved mechanical strength. Incorporating TDPPI into epoxy proved to be a game-changer, with SEM studies confirming its uniform dispersion and excellent compatibility with the epoxy matrix. Differential scanning calorimetry showcased that a mere 2.5 wt% of TDPPI led to 100% curing, achieving a glass transition temperature of 43.8°C. The thermogravimetric study unveiled a remarkable 23% increase in residual mass at 600°C when 2.5 wt% of TDPPI was introduced to the epoxy. Notably, the epoxy thermoset compounded with this minimal TDPPI concentration passed the stringent Underwriter’s Laboratory (UL-94) test with a V-1 classification. Furthermore, it achieved a limiting oxygen index of 30.7%, accompanied by a significant 58.7% reduction in burning rate. At a conservative 1.5 wt% of TDPPI, the resulting epoxy thermoset exhibited remarkable enhancements across various mechanical properties. Tensile strength saw a notable 23% increase, Young’s modulus soared by 37%, flexural strength showed a 9% improvement, and Izod impact strength experienced an impressive surge of 37%, all in comparison to the neat epoxy. In conclusion, the addition of 2.5 wt% of TDPPI emerged as the sweet spot for achieving flame retardancy in epoxy composites while simultaneously enhancing mechanical strength. The maleimide-phosphorus synergistic effect showcased TDPPI’s prowess as a promising flame retardant material, marking a significant advancement in the quest for high-performance epoxy formulations in the plastics engineering landscape. *You can read more about this topic in the article “*[Revolutionizing epoxy performance: A new flame retardant with phosphorus and maleimide for enhanced cure behavior, thermal stability, flame retardancy, and mechanical properties](https://4spepublications.onlinelibrary.wiley.com/doi/ftr/10.1002/pen.26497) *” by [Ayyappan Ranjith](https://4spepublications.onlinelibrary.wiley.com/authored-by/Ranjith/Ayyappan) , [Arunjunai Raj Mahendran](https://4spepublications.onlinelibrary.wiley.com/authored-by/Mahendran/Arunjunai+Raj) , [Thangamani Rajkumar](https://4spepublications.onlinelibrary.wiley.com/authored-by/Rajkumar/Thangamani) , published in the September 2023 issue of Polymer Engineering and Science and chosen as the Editor’s Choice article for December 2023.* By **[Plastics Engineering](https://www.plasticsengineering.org/author/pe-anonymous/)** | December 16, 2023 ##### [Plastics Engineering](https://www.plasticsengineering.org/author/pe-anonymous/) [+ postsBio ⮌](#) ### Other posts you could read [April 27, 2026Nanocomposite Films from Car Bumper Waste](https://www.plasticsengineering.org/2026/04/nanocomposite-films-from-car-bumper-waste-011041/) [April 23, 2026Conductive Polymers Revolutionize Fuel Cell Plates](https://www.plasticsengineering.org/2026/04/conductive-polymers-revolutionize-fuel-cell-plates-011057/) [April 29, 2026Renewable Functional Coatings for Advanced Applications](https://www.plasticsengineering.org/2026/04/renewable-functional-coatings-for-advanced-applications-011134/) [April 24, 2026Emerging Markets for Polyolefins in the Solar Industry](https://www.plasticsengineering.org/2026/04/emerging-markets-for-polyolefins-in-the-solar-industry-011128/) [April 9, 2026RecyQMeter: Quantifying Recycled Plastic Quality](https://www.plasticsengineering.org/2026/04/recyqmeter-quantifying-recycled-plastic-quality-010917/) [April 20, 2026Real-Time Melt Monitoring in Extrusion and Injection Molding](https://www.plasticsengineering.org/2026/04/real-time-melt-monitoring-in-extrusion-and-injection-molding-011167/) [May 1, 2026High-Viscosity Photopolymers Transform Additive Manufacturing](https://www.plasticsengineering.org/2026/05/high-viscosity-photopolymers-transform-additive-manufacturing-011153/) [April 14, 2026How to Test for Chemical Resistance in Plastic Components](https://www.plasticsengineering.org/2026/04/how-to-test-for-chemical-resistance-in-plastic-components-010963/) ## Share Your Thoughts [Cancel reply](/2023/12/flame-retardancy-in-epoxy-the-tdppi-breakthrough-002935/#respond) - 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