摘要
为改善不透性石墨用浸渍剂酚醛树脂的耐高温性,用H3BO3和甲基三甲氧基硅烷(MTMS)为改性剂,制得B改性(BPF)和B/Si共改性的酚醛树脂(B/SiPF)。研究结果表明,改性后B和Si原子接枝到树脂分子链中,形成B-O-C、Si-O-B键,热解温度t5%从改性前的342℃提高到353℃(BPF)和367℃(B/SiPF),残炭率可达70%(1000℃)。此外BPF-L和B/SiPF-L与石墨的接触角分别从改性前的117.5°降低到64°和49°,改善了对石墨的浸润性。BPF和B/SiPF均可改善浸渍石墨的力学性能和耐高温性,且B/SiPF树脂能深入石墨的微小孔隙,结合更稳定,浸渍封孔效果更好。B/SiPF浸渍石墨的氧化失重率仅0.40%(350℃空气),抗弯强度23.55 MPa,比改性前提高11.88%。
In order to improve the high temperature resistance of phenolic resin for impermeable graphite,B-modified(BPF)and B/Si co-modified phenolic resins(B/SiPF)were produced using H3 BO3 and methyltrimethoxysilane(MTMS)as modifiers,respectively.The results show that B and Si atoms are grafted into the molecular chain of the resin to form B—O—C and Si—O—B with large bond energy in the modification,respectively.The pyrolysis temperatures t5%of modified phenolic resin are increased from 342℃(unmodified PF)to 353℃for BPF and 367℃for B/SiPF,and the char yield of 1000℃is as high as 70%.Additionally,the wettability of modified phenolic resins on graphite has been improved.The contact angles of BPF-L and B/SiPF-L with graphite are reduced from 117.5°(before modification)to 64°and 49°,respectively.Both BPF and B/SiPF can improve the mechanical strength and high temperature resistance of impregnated graphite.The B/SiPF resin can penetrate into the tiny pores of graphite,which makes the combination more stable and the sealing effect better,so it is more suitable as an impregnating agent for impermeable graphite.The oxidation weight loss of B/SiPF resin-impregnated graphite is only 0.40%in air at 350℃,and the bending strength of impregnated graphite is 23.55 MPa,which is 11.88%higher than that of the unmodified PF.
作者
刘雯
常青
雷世文
刘犇
刘占军
夏斌
王俊飞
Liu Wen;Chang Qing;Lei Shi-wen;Liu Ben;Liu Zhan-jun;Xia Bin;Wang Jun-fei(Key Laboratory of Carbon Materials,Institute of Coal Chemistry,Chinese Academy of Sciences,Shanxi Taiyuan 030001,China;School of Energy and Power Engineering,North University of China,Shanxi Taiyuan 030051,China;Nantong Xingqiu Graphite Equipment Co.,Ltd.,Jiangsu Nantong 226500,China)
出处
《炭素技术》
CAS
北大核心
2024年第5期49-54,共6页
Carbon Techniques
基金
山西省重点实验室开放基金资助项目(2022HPB M02001)。
关键词
改性酚醛树脂
耐高温性
浸渍石墨
抗弯强度
Modified phenolic resin
high-temperature resistance properties
impregnated graphite
bending strength