氧化石墨烯在膨胀型水性防火涂料中阻燃和抑烟作用研究

Effects of Graphene Oxide on Flame Retardancy and Smoke Suppression of Waterborne Intumescent Fire Resistant Coatings

以水性丙烯酸乳液为成膜物质,钛白粉为颜料,加入不同量氧化石墨烯(GO)纳米粒子作为协效阻燃/抑烟剂配制膨胀型防火涂料,采用大板燃烧法、锥形量热仪和烟密度测试法对其阻燃和抑烟效果进行了研究。结果表明:GO能有效地提高涂料试样的耐燃时间和降低峰值生烟速率(p SPR),当GO添加量为0.025份时(以100份乳液计,下同),试样耐燃时间可以增加59.5%,当添加量为0.125份时试样的p SPR从0.024 m2/s降至0.013 m2/s。结合扫描电镜(SEM)、热重分析(TG)、差热分析(DTA)和红外光谱(FT-IR)等手段对试样炭层的结构形貌进行分析后发现,具有片状结构的氧化石墨烯在涂料受热膨胀过程中会使自身和基体分子链取向,进而在聚合物炭化过程中形成骨架结构增加炭层强度,达到阻燃和抑烟的目的。

Intumescent fire retardant coatings were prepared from waterborne acrylic emulsion as matrix material and titanium dioxide as pigment as well as different amounts of graphene oxide （GO） nanoparticles as synergistic flame retardants/smoke suppressants. The effects of GO on the flame-retardant and smoke-suppressing properties of coatings were investigated by cone calorimeter, smoke density tester and big panel method. The results indicated that the fire resisting time of samples was increased by 59. 5% at the presence of GO 0. 025 phr, and peak smoke production rate （pSPR） was decreased from 0. 024 to 0. 013 m^2/s when GO dosage was 0. 125 phr. The morphology of charting layers was characterized by scanning e- lectron microscopy （SEM） ,thermogravimetry （ TG）, differential thermal analysis （DTA） and Fourier transform infrared spectroscopy （FT- IR）, revealing that GO nanosheets and the chains between them were orientated during the intumescence char forming process and could generate skeleton, which have been believed to be the main contribution to the enhancement of both flame retardancy and smoke suppression.