Nanoparticles can provide flame retardance to hosting polymers and act as nano fire extinguishers. Hydroxyapatite （Ca5（OH）（PO4）3） （HA） is not hygroscopic, and is thermally stable up to 800℃, with 18.5 wt% pho...Nanoparticles can provide flame retardance to hosting polymers and act as nano fire extinguishers. Hydroxyapatite （Ca5（OH）（PO4）3） （HA） is not hygroscopic, and is thermally stable up to 800℃, with 18.5 wt% phosphorous content. It is this high phosphorous content that can provide HA with flame retardant properties. In this paper, we report on the continuous synthesis of ultrafine HA using a hydrothermal synthesis technique. The HA surface properties were changed from hydrophilic to hydrophobic by post-synthesis surface modification. The ratio of the HA nanoparticles and an intumescent agent known as Exolit AP750 was investigated to yield a self-extinguishing multi-component epoxy nanocomposite for extended application under extreme fire conditions. The HA/AP750/epoxy nanocomposite was able to resist a flame at 1700 oc and self-extinguish after the flame had been removed. The nanocomposite showed an enhanced flammability performance in standard cone calorimetry testing and formed a compact and cohesive protective char layer with a 50% decrease in peak heat released compared with virgin epoxy. Our aim was to establish the use of HA as an effective nanofiller with phosphorous-based flame retardant properties. The surface of this nano fire extinguisher was modified effectively with different surfactants for enhanced compatibility with different polymeric matrices.展开更多
In this work, a phosphorous-based compound （DOPO-ICN） was obtained by a two-step process. 9,10-dihydro-9-oxa-10- phosphaphenanthrene-10-oxide （DOPO） reacted with formaldehyde firstly, followed with reacting with 1...In this work, a phosphorous-based compound （DOPO-ICN） was obtained by a two-step process. 9,10-dihydro-9-oxa-10- phosphaphenanthrene-10-oxide （DOPO） reacted with formaldehyde firstly, followed with reacting with 1,6-hexane diisocyanate （HD1）. The chemical structure of DOPO-ICN was confirmed by Fourier transform infrared spectroscopy （FTIR） and 1H NMR. The influence of DOPO-1CN on the mechanical and flammability properties ofjute/PLA composites was studied. Compared to DOPO, DOPO-ICN improved the tensile, flexural and impact strength of the flame retardant jute/PLA composites. Moreover, the flammability ofjute/PLA composites with different DOPO and DOPO-MA loading was investigated by thermogravimetric analysis （TGA）, UL 94 test and limiting oxygen index （LOI） measurements. The results showed that DOPO-ICN imparted the flame retardancy to the jute/PLA composites.展开更多
基金Financial support of the research project entitled "Enhanced Flame Retardant Polymer Nanocomposites" has been provided by the Egyptian Military Technical College,Cairo,Egypt
文摘Nanoparticles can provide flame retardance to hosting polymers and act as nano fire extinguishers. Hydroxyapatite （Ca5（OH）（PO4）3） （HA） is not hygroscopic, and is thermally stable up to 800℃, with 18.5 wt% phosphorous content. It is this high phosphorous content that can provide HA with flame retardant properties. In this paper, we report on the continuous synthesis of ultrafine HA using a hydrothermal synthesis technique. The HA surface properties were changed from hydrophilic to hydrophobic by post-synthesis surface modification. The ratio of the HA nanoparticles and an intumescent agent known as Exolit AP750 was investigated to yield a self-extinguishing multi-component epoxy nanocomposite for extended application under extreme fire conditions. The HA/AP750/epoxy nanocomposite was able to resist a flame at 1700 oc and self-extinguish after the flame had been removed. The nanocomposite showed an enhanced flammability performance in standard cone calorimetry testing and formed a compact and cohesive protective char layer with a 50% decrease in peak heat released compared with virgin epoxy. Our aim was to establish the use of HA as an effective nanofiller with phosphorous-based flame retardant properties. The surface of this nano fire extinguisher was modified effectively with different surfactants for enhanced compatibility with different polymeric matrices.
基金supported by the Ministry of Industry and Information Technology of China(Grant No.MJ-2015-H-G-103)the National Natural Science Foundation of China(Grant Nos.51103108,11172212)the Fundamental Research Funds for the Central Universities
文摘In this work, a phosphorous-based compound （DOPO-ICN） was obtained by a two-step process. 9,10-dihydro-9-oxa-10- phosphaphenanthrene-10-oxide （DOPO） reacted with formaldehyde firstly, followed with reacting with 1,6-hexane diisocyanate （HD1）. The chemical structure of DOPO-ICN was confirmed by Fourier transform infrared spectroscopy （FTIR） and 1H NMR. The influence of DOPO-1CN on the mechanical and flammability properties ofjute/PLA composites was studied. Compared to DOPO, DOPO-ICN improved the tensile, flexural and impact strength of the flame retardant jute/PLA composites. Moreover, the flammability ofjute/PLA composites with different DOPO and DOPO-MA loading was investigated by thermogravimetric analysis （TGA）, UL 94 test and limiting oxygen index （LOI） measurements. The results showed that DOPO-ICN imparted the flame retardancy to the jute/PLA composites.
