阻燃及可瓷化硅橡胶成炭结构的研究进展

简单介绍了硅橡胶的阻燃和瓷化机理。依据阻燃剂、填料及炭层结构的不同,将硅橡胶分为阻燃和可瓷化两大类,综述了阻燃硅橡胶和可瓷化硅橡胶的阻燃性能和成炭结构的研究进展。分析表明:添加物理或化学膨胀型阻燃剂的硅橡胶,燃烧过程中形成的炭层疏松多孔,阻燃隔热性能优异,但炭层强度差;添加非膨胀型阻燃剂的硅橡胶,炭层结构相对密实,但表面不平整,存在孔洞和裂缝,阻燃效果不好;添加可瓷化填料的硅橡胶燃烧形成的陶瓷炭层坚硬而致密,具有优异的耐火持久性,但在隔绝热量方面不如膨胀炭层。炭层的疏松隔热与坚固耐久兼顾是阻燃硅橡胶未来可能的发展方向。

Research Progress on the Char Structure of Flame Retardant and Ceramifiable Silicone Rubber

The flame retardant mechanism and ceramifiable mechanism of silicone rubber were briefly introduced.According to the difference in flame retardant,fllers and char layer structure,silicone rubber was divided into two categories,flame retardant and porcelain.The research progress of flame retardant properties and char formation structure of flame retardant silicone rubber and ceramicizable silicone rubber were reviewed.The analysis shows that the char layer formed during combustion was loose and porous if the silicone rubber was flleld with physical or chemical intumescent flame retardant.The char had excellent flame retardant and heat insulation performance.but poor strength.Silicon rubber with non intumescent flame retardants had relatively dense carbon layer structure,but its surface was not uniform with holes and cracks on it.The flame retardant ffect was not good.The ceramic char layer formed by the combustion of the ceramic rubber flled with the porcelain fllr was hard and compact.The char layer has excellent refractory durability,but was inferior to the expanded char layer in terms of heat insulation.The char layer has both loose insulation and solid durability,which may be the possible development direction of flame retardant silicone rubber in the future.