A Study on Phosphorous-Based Flame Retardants for Transparent PET Composites: Fire, Mechanical, and Optical
Sara Villanueva-Díez1, Alberto Sánchez-de-Andrés1
1TECNALIA, Basque Research and Technology Alliance (BRTA), Parque Científico y Tecnológico de Gipuzkoa Mikeletegi Pasealekua, 2, E-20009 Donostia-San Sebastián, Gipuzkoa, Spain.
Polymers
|August 28, 2025
Summary
Flame-retardant poly (ethylene terephthalate) composites offer improved fire resistance. An organic phosphonate achieved a V0 rating, demonstrating effective flame retardancy for flexible, transparent applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Fire Safety Engineering
Background:
- Poly (ethylene terephthalate) (PET) composites are explored for flexible and transparent applications.
- Flame retardants are crucial for enhancing the fire safety of polymer-based materials.
Purpose of the Study:
- To develop flame-retardant PET (FR PET) composites.
- To evaluate the fire reaction, transparency, and mechanical properties of FR PET composites with various phosphorus-based flame retardants.
Main Methods:
- Melt blending of low-molecular-weight PET with phosphorus-based flame retardants.
- Thermogravimetric Analysis (TGA) and Cone Calorimetry for fire performance assessment.
- UL94 standard testing for flammability classification.
Main Results:
- Addition of flame retardants reduced heat generation and improved the fire growth index (FGI).
- An organic phosphonate (Aflammit PCO900) achieved UL94 V0 classification due to gas-phase action and plastification.
- Flame retardants decreased transparency but maintained good optical performance; crystallization parameters were unaffected.
Conclusions:
- Organic phosphonates are effective flame retardants for PET, enabling V0 classification.
- Flame retardancy mechanisms involve gas-phase inhibition and polymer removal from the flame.
- Reduced transparency in FR PET is linked to flame retardant miscibility and refractive index differences.
Keywords:
DOPOarylphosphatescyclotriphosphazeneflame-retardant transparent PETphosphonated organic flame retardantphosphorous-based flame retardantprinted electronicsMore Related Videos
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