杨东亚
,
祁渊
,
王宏刚
,
高贵
,
龚俊
,
任俊芳
功能材料
doi:10.3969/j.issn.1001-9731.2015.10.010
通过机械共混、冷压成型、烧结的方法制备聚醚醚酮(PEEK)与纳米 SiO2颗粒共同填充改性聚四氟乙烯(PTFE)复合材料试样。利用 MRH-3型环-块摩擦磨损实验机对不同配方比例的复合材料在不同实验条件下进行摩擦学性能实验。利用扫描电镜对试样磨损后的摩擦表面形貌和钢环表面的转移膜进行观察和分析。结果表明，填充5％PEEK 的 PTFE 复合材料的摩擦系数达到最低值；10％PEEK/PTFE 复合材料中添加不同体积比的纳米 Si O 2填料可以显著地降低材料的体积磨损率，其中5％Nano-SiO2/10％PEEK/PTFE复合材料的体积磨损率最小；载荷和速度的变化对 Nano-SiO2/PEEK/PTFE 复合材料的摩擦磨损性能的影响显著，而环境温度的变化对该复合材料的摩擦系数与磨损率的影响不明显。
关键词:
Nano-SiO2
,
PEEK
,
PTFE
,
摩擦磨损
Ruijing ZHANG
,
Ke YANG
,
Tianying XIONG
材料科学技术（英）
Nano-SiO2 with high activity and mesopores was prepared through sol-gel synthesis followed by low-temperature heat treatment and ball milling firstly in our experiments. TEM was performed to measure particle sizes. Nitrogen adsorption experiments were carried out to estimate specific surface area, porous distribution and porous ratio by BET and BJH methods. The content of Si-OH in SiO2 surface was calculated by analysis of the results of hydrogen-oxygen content mensuration (HOCM). As a result, appropriate heat treatment system and ball milling time are important to preparation for nano-SiO2 with high activity and mesopores, which are 5~50 nm particles, 5~6 nm average aperture, 85%~93% porous ratio, and 51%~55% Si-OH content in surface. Nano-SiO2 with that structure has high surface energy and activity. This process, which has simple facilities and operation rules, is a new way of preparation for nano-SiO2 with high activity and mesopores.
关键词:
Heat treatment
,
null
,
null
,
null
史洪微刘福春韩恩厚
腐蚀科学与防护技术
研究了含量为10%和30%的硅烷偶联剂处理前后的纳米SiO2对涂覆LY12铝合金上的环氧清漆耐腐蚀性能的影响.扫描电镜形貌表明，添加未处理的纳米SiO2，涂层树脂中的SiO2以团聚体的状态存在，经过硅烷偶联剂处理的纳米SiO2与树脂呈一体状态.3.5%NaCl溶液中浸泡1200小时的电化学阻抗谱(EIS)的研究表明，加入10％未处理纳米SiO2的清漆浸泡24小时后出现不明显的第二个时间常数，但含量为30%的清漆则由于团聚的效应在浸泡初期比前者出现更明显的第二个时间常数;添加10％硅烷偶联剂处理后纳米SiO2增强了清漆的耐腐蚀性，添加30％硅烷偶联剂处理后纳米SiO2的清漆具有最好的耐腐蚀性，两者在整个浸泡过程中体现一个时间常数的特征.
关键词:
纳米SiO2
,
EIS
,
epoxy varnish
,
silane crosslinker
Zhenyu Wang Enhou Han Fuchun Liu Wei Ke
材料科学技术（英）
The nano-concentrates and fiame retardant nano-coating were prepared in thhis study. The effect of nano-SiO2 on the corrosion resistance and fire resistance of ammonium polyphosphate-pentaerythritol-melamine (APP-PER-MEL) coating was investigated by differential thermal analysis (DTA), scanning electron microscopy
(SEM), effective thermal conductivity (λ/d), X-ray photoelectron spectroscopy (XPS) and fire protection test. The chemical action and endothermic effect of ammonium polyphosphate, pentaerythritol and melamine in traditional flame retardant coating were damaged by salt spray condition, whereas the flame-retardant additives in the nano-coating demonstrated the good chemical interaction in salt spray condition. The uniformly dispersed nano-SiO2 particles could improve corrosion resistance of the coating, and hence nano-coating could remain the good fire-resistant properties even after 500 h salt spray test.
关键词:
Nano-SiO2
