Investigation of Flame Retardant Flexible Polyurethane Foams Containing DOPO Immobilized Titanium Dioxide Nanoparticles

• Published in: Polymers Vol. 11; no. 1; p. 75
• Main Authors: Dong, Quanxiao, Chen, Keyu, Jin, Xiaodong, Sun, Shibing, Tian, Yingliang, Wang, Feng, Liu, Peng, Yang, Mingshu
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 05.01.2019; MDPI
• Subjects: Carbon dioxide; Char formation; Enthalpy; flame retardant; Flame retardants; Fourier transforms; Heat; Heat release rate; Incorporation; Infrared analysis; Infrared spectra; Nanoparticles; Plastic foam; Polymer blends; Polymers; polyurethane; Polyurethane foam; Solvents; Stability analysis; supercritical carbon dioxide; surface modification; Thermal stability; Thermogravimetric analysis; Titanium; Titanium dioxide; China; titanium dioxide; supercritical carbon dioxide; polyurethane; flame retardant; surface modification
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym11010075

In this work, a multi-functional nanoparticle (TiO₂-KH570-DOPO) has been successfully synthesized through the attachment of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-methacryloxy propyl trimethoxyl silane on the surface of titanium dioxide (TiO₂). Supercritical carbon dioxide was used as the solvent in order to increase the grafting level. The chemical structure of TiO₂-KH570-DOPO was fully characterized using Fourier transform infrared spectra, thermogravimetric analysis and transmission electron microscopy. The modified TiO₂ was incorporated into flexible polyurethane foam (FPUF). The fire performance of FPUF blends was evaluated using microscale combustion calorimetry. Peak heat release rate and total heat release values were reduced from 657.0 W/g and 28.9 kJ/g for neat FPUF sample to 519.2 W/g and 26.8 kJ/g of FPUF specimen containing 10 wt % of TiO₂-KH570-DOPO. Analysis of thermal stability and the observation of char formation suggests that TiO₂-KH570-DOPO is active in the condensed phase.