金屬氫氧化物與奈米黏土於EVA防火相乘效應之研究

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

黃春萍(Chun-Ping Huang)

指導教授 ： 郭文正

國立臺北科技大學/工程學院/化學工程所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00178

摘要

本研究以金屬氫氧化物結合奈米黏土作為EVA的無鹵阻燃劑，並在固定的阻燃劑添加量下變化奈米黏土與金屬氫氧化物之間的組成比例，再經由LOI、UL-94與Cone calorimeter的燃燒測試來篩選阻燃劑的最佳組成比例。同時探討添加無鹵阻燃劑對EVA熱安定性與機械性質的影響。另外，對金屬氫氧化物劑與奈米黏土之間的防火相乘效應的作用機制也作初步的探討。
實驗結果顯示，使用含適當量奈米黏土的無鹵阻燃劑配方，可提高試片的LOI值與UL-94阻燃等級，試片在Cone calorimeter test的尖峰熱釋放率與遮煙係數也會明顯降低。試片的熱安定性與機械性質會隨著無鹵阻燃劑配方中奈米黏土含量的增加而提升。在無鹵阻燃級EVA中，以EVA50wt%/MH48wt%/Clay2wt%及EVA50wt%/ATH49wt%/Clay1wt%有最佳的阻燃性。金屬氫氧化物與奈米黏土之間的防火相乘效應在於試片燃燒時金屬氫氧化物可吸熱分解與釋放水氣來降低試片的溫度及稀釋可燃氣體外，奈米黏土可結合熱分解產生的金屬氧化物，在燃燒的表面形成緻密的阻隔層可抑制熱與燃料氣體的傳送，達到最佳的防火相乘效應。

關鍵字

金屬氫氧化物 ； 奈米黏土 ； 防火相乘效應 ； 阻燃機制

並列摘要

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.

並列關鍵字

Metal hydroxide ； Nanoclay ； Synergistic effect ； Flame retardantmechanism

參考文獻

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