鐘瑤冰,魏伯榮,劉郁楊
(西北工業大學 理學院 高分子研究所,陜西 西安 710129)
燒蝕材料高成碳樹脂的研究進展
鐘瑤冰,魏伯榮,劉郁楊
(西北工業大學 理學院 高分子研究所,陜西 西安 710129)
耐燒蝕材料在國防工業上有十分重要的應用價值,碳化型燒蝕材料是利用高分子材料在高溫碳化吸熱量的材料。樹脂基燒蝕材料一般要求具有高相對分子質量、高芳基化、高交聯密度、高C/O比,以使材料燒蝕后成碳率高。材料的燒蝕率與成碳率成反比關系,樹脂的成碳率越高,其耐燒蝕性能越好。材料的成碳率高低由樹脂的化學結構決定。目前燒蝕材料的研究方向是:成碳率高、比熱大、熱導率小、密度小、碳化層強度高、熱分解溫度高的材料。綜述了改性酚醛樹脂:酚三嗪樹脂、硼酚醛樹脂及聚芳基乙炔樹脂的合成、燒蝕性能、高成碳率的研究近況,并對今后燒蝕材料的研究作了展望。
燒蝕材料;改性酚醛樹脂;聚芳基乙炔樹脂;成碳率;燒蝕性能
Abstract:Ablation-resistant materials play an important role in the defense industry,carbon-based ablative material is a kind of material which uses the feature that the carbonization of polymer material at high temperature can absorb heat.General requirements for resin-based ablative material are high molecular weight,high-arylation,high crosslinking density and high C/O ratio,so that the carbonization rate of materials can be higher after ablation.Material ablation rate is inversely proportional to the carbonization rate.The resin which has higher carbonization rate will possess better resistance to ablation.The carbonization rates of material are mainly determined by the chemical structure of resin.At present,the research trends of ablative material are summarized as follows:high carbonization rate,large specific heat capacity,low thermal conductivity,small density,carbon layer with high strength and high thermal decomposition temperature.The recent studies are summarized,such as on the synthesis of modified phenolic resin:phenolic triazine resin,boron phenolic resin and polyarylacetylene resin,ablation performance and high carbonization rates.And the future research on ablative material is prospected.
Key words:Ablative material;modification phenolic resins;polyarylacetylene resin;carbonization rate;ablation performance
熱防護材料即通常所稱的耐燒蝕材料在國防工業上有十分重要的應用價值,它可用作火箭發動機的內絕熱層、火箭噴管材料、戰略導彈彈頭的防熱材料,以及航天飛機、飛船、返回式衛星的外部防熱結構等[1,6]及民用的燒蝕涂料、防火涂料。對航天器進行熱防護研究,燒蝕法是有效、廣泛使用的一種方法,它是以消耗物質來換取防熱效果的積極防熱方式,它的最大優點是安全可靠,適應流場變化的能力強,在高熱流條件下,它是唯一可行的防熱方法。……