Synergistic Effect of Metal Hydroxide and Nanoclay on Fire Retardancy of EVA

• Main Authors: Chun-Ping Huang, 黃春萍
• Other Authors: 郭文正
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/rj58rs

碩士 === 國立臺北科技大學 === 化學工程所 === 93 === In this study, EVA, combination of metal hydroxide and nanoclay was employed as halogen-free flame retardant for EVA. Fire test such as LOI, UL-94 and Cone calorimeter were employed to evaluate the optimum combination ratio between metal hydroxide and nanoclay at a fixed additive level of halogen-free flame retardant. Effects of halogen-free flame retardant addition on thermal stability and mechanical properties of EVA were also investigated in this work. Besides, the synergistic effect of metal hydroxide-nanoclay on flame retardant mechanism of EVA was proposed. Experimental results indicate that flame retarded EVA specimens containing a suitable amount of clay can gain a higher LOI value and better UL-94 rating. These specimens also give the lower values of pk-HRR and extinction coefficient on Cone calorimeter test. Thermal and mechanical properties of flame retarded EVA are improved with the increasing of clay content in the specimen. The specimen shown the best performance on fire retardancy is EVA50wt%/MH48wt%/Clay2wt% and EVA50wt%/ATH49wt%/Clay1wt%. The metal oxide protective layer on burning surface is reinforced by reassembling silicate layers to give an expanded and compacted surface insulated layer. This insulated layer is suggested to respond for the synergistic effect on flame retardancy as well as on smoke suppressing observed in flame retarded EVA.