摘要
有机硅泡沫(SiF)在高温热流或火焰中发生分解,留下疏松脆弱易坍塌的残余物,完全丧失原有的密封、隔热、绝缘等优异特性,借助新兴的高温陶瓷化技术可较好地解决这一问题.首先将蒙脱土、低熔点玻璃粉、镁铁层状双氢氧化物(LDH)在SiF发泡前与基胶预混均匀,然后正常交联产气发泡制得高温可陶瓷化SiF复合材料.通过对不同温度煅烧后的SiF陶瓷体进行压缩强度、微观形貌以及晶体结构等表征,从而推断可陶瓷化SiF在高温环境中的陶瓷化演变过程.其中,LDH作为一种高温陶瓷化协效剂,不仅可以减少SiF残余物中的缺陷,而且可以加快复合材料的陶瓷化转变进程,进一步提升陶瓷体的力学强度,使得1000℃煅烧后SiF的压缩强度与煅烧前相比提高约25倍,达到517 kPa.由于陶瓷化体系的构建,最终实现了SiF在高温环境中向致密连续且强硬的陶瓷体转变,为SiF的高温防火提供了一种切实可行的途径.
Silicone foam(SiF)decomposes in high-temperature heat flow or flame,leaving loose,fragile and easily collapsed residues,completely losing its original excellent characteristics such as sealing,heat insulation,and insulation.This problem may be well solved with the help of emerging high-temperature ceramizable technology.First,montmorillonite,low-melting glass powder,and layered double hydroxide(MgFe-LDH)are pre-mixed with silicone oil before SiF foaming,and then cross-linking and gas-generating foaming are carried out to obtain the high-temperature ceramizable SiF material.By characterizing the compressive strength,microscopic morphology,and crystal structure of SiF ceramic residues sintered at different temperatures,the ceramization evolution process of ceramizable SiF during high-temperature environments can be inferred.As a hightemperature ceramization synergist,LDH can not only reduce defects in SiF residues but also accelerate the ceramization transformation process of the material,and further enhance the mechanical strength of the ceramic residue.The compressive strength of the material after sintering at 1000℃reaches 517 kPa,which is about 25 times higher than that of the original.Owing to the construction of the ceramizable system,the transformation of SiF to dense continuous,and tough ceramic foam in high temperature environment is realized,which provides a practical approach for the high-temperature fire resistance of SiF.
作者
李文雄
汪秀丽
赵海波
王玉忠
Wen-xiong Li;Xiu-li Wang;Hai-bo Zhao;Yu-zhong Wang(College of Architecture and Environment,The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MOE),State Key Laboratory of Polymer Materials Engineering,National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan),Sichuan University,Chengdu 610064)
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2023年第3期381-389,共9页
Acta Polymerica Sinica
基金
国家重点研发计划项目(项目号2020YFB0311300)资助.
关键词
层状双氢氧化物
高温陶瓷化协效剂
有机硅泡沫
陶瓷化演变
耐高温
Layered double hydroxide
High-temperature ceramizable synergist
Silicone foam
Ceramization evolution
High temperature resistance
