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耐腐蚀石墨衬里传统上是用石墨板勾缝材料砌筑,且施工复杂、工期长、要求严格.该文介绍了以石墨粉为基材、酸醛树脂为粘结剂配制而成的浇注科,以浇注法制作大型石墨衬里的成功实例.用此法可实现大型石墨衬里的整体浇注. 相似文献
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通过对酚醛树脂浸渍石墨的强度、温度、硬度、耐腐蚀性的分析,说明固定错气盘采用酚醛树脂浸渍石墨制作是可行的,对其结构进行相应在改进后,能够保证错气盘效果良好,延长使用寿命,降低检修人员的劳动强度 。 相似文献
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采用酚醛树脂对石墨进行改性处理,制得改性石墨/天然橡胶(NR)复合材料,采用扫描电子显微镜对石墨的微观形貌进行了表征,并对改性石墨/NR复合材料的性能进行了研究。结果表明,改性石墨的表面粗糙度增加。改性石墨/NR复合材料在不同温度下的平均热导率高于未改性石墨/NR复合材料;随着酚醛树脂含量的增大,复合材料导热性能有所降低。与未改性石墨/NR复合材料相比,改性石墨/NR复合材料的拉伸强度、撕裂强度、定伸应力和硬度增大,扯断伸长率和永久变形降低;酚醛树脂含量高的改性石墨/NR复合材料较酚醛树脂含量低的复合材料力学性能有所降低。 相似文献
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Hyperbranched polyborate (HBPB) is a new polymer with highly branched structures, plenty of functional end groups and excellent thermal resistance, which can be used as a positive modifier for phenolic resin (PR) to greatly increase the carbon yield of PR. In the present article, thermal properties and structural changes of HBPB modified PR (PR‐HBPB) during the pyrolysis are studied. The pyrolysis mechanism of PR‐HBPB is proposed to explain the increase of the carbon yield of PR‐HBPB. It is found that the carbon yields of PR‐HBPBs containing 10 and 20 wt% of HBPB are 71.3 and 73.1% at 800°C in nitrogen, which are higher than those of PR and HBPB but not the sum of the carbon yields of PR and HBPB in consideration of their mixing ratio. The increase of carbon yield of PR‐HBPB can be attributed to the combined effects of the excellent thermal stability of HBPB, the formation of BC3 and B2O3, promoted graphitization by HBPB and the protection of B2O3 on the edges of the graphite microcrystallites. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers 相似文献
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有机硼改性酚醛树脂的合成 总被引:9,自引:4,他引:9
以硼酸,苯酚,甲醛为原料,碳酸钠作催化剂合成具有耐高温性能的硼酚醛树脂。通过IR,对这种热固性有机硼改性酚醛树脂的结构进行了表征。树脂的热失重分析结果表明此树脂耐热性优于普通酚醛树脂,所得产物在900℃残留物为76.38%。确定了最佳反应条件为:苯酚:甲醛:硼酸=1:2:0.3(摩尔比),缩合反应温度70-75℃,硼酯化反应温度100-104℃,在控制反血时间下脱水一次。 相似文献
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