油酸钠改性对凹凸棒黏土理化性能的影响.pdf

第20卷第9期
中国矿业
2011年9月
CHINA MNNG MAGAZNE
Sep.2011
油酸钠改性对凹凸棒黏土理化性能的影响
徐继香2,康玉茹,王爱勤
(1.中国科学院兰州化学物理研究所,せ肃兰州73000:2.中国科学院研究生院,北京100049
摘要:用阴离子表面活性剂油酸钠对凹凸棒黏土进行有机改性,探讨了油酸钠用量、PH值和反
应温度对有机改性的影响。通过红外光谱、流変和电位测定,比较了改性前后四凸棒黏土的理化性
质。结果表明,随油酸钠用量的增加有机化度逐渐增大,随pHI值的增加有机化度先增大后减小,反应
温度对有机化度没有本质影响。红外光谱表明,油酸根已结合在凹凸棒黏土的表面;流变和て电位结果
表明,油酸根通过静电和空间位阻作用影响悬浮液黏度;在油酸钠用量为黏土量4.56%时,所得有机凹
凸棒黏土剪切黏度最低。
关键词:四凸棒黏土;油酸钠;有机政性;流变性;电位
中图分类号:P578.965文献标识码:B文章编号:1004-4051{2011)09-0102-04
Effects of sodium oleate on physicochemical properties of the modified attapulgite
XU Ji-xiang.2 KANG Yu-ru, WANG Ai-qin
(1. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China;
2. Graduate University of Chinese Academy of Scicnces, Beijing 100049, China)
Abstract Organically modified attapulgite clays were prepared using sodium oleate as modifier. The in-
fluences of sodium oleate concentrations, ph values and temperatures on the organification reaction were in-
vestigated, The physicochemica! properties of raw attapulgite and organo-attapulgite clays were character
ized by infrared spectroscopy, rheometer and potential. The results showed that the organification degree
of attapulgite increases with increasing the concentration of sodium olcate, while the organification degree
firstly increases with increasing PH value, reaching a maximum and then decreases. No obvious influence of
temperature on reactions can be observed. The infrared spectroscopy showed that oleate anions were already
adsorbed onto attapulgite surfaces. The rheological and electrokinetic properties showed that the viscosities
of suspensions modified by different levels of sodium oleate were controlled by electrostatic and steric inter
actions, and the lowest viscosity of suspension was obtained when 4.56% sodium oleate was added to the
suspension.
Key words: attapulgite clay; sodium oleate; organically modify; rheological property; potenti
凹凸棒黏土( Attapulgite,APT)是一种含水是常用的处理方式?,而直接采用阴离子表面活
富镁铝的硅酸盐矿物,独特的棒结构使其成为性剂改性APT的研究报道较少。采用阴离子表面
聚合物材料理想的功能填料。然而,APT在形成活性剂改性APT,通常是在其表面先包覆金属氧
过程中,由于类质同晶置换现象,使其呈亲水性,化物,使表面带正电后再用阴离子表面活性剂改
与聚合物的相容性差,限制了在塑料、油性涂料性副;也可以先使APT在酸性或碱性条件下质子
和橡胶等方面的应用。为了解决APT在聚合物基化或去质子化,从而使黏土表面带正电或负电,
质中的分散问题,需对其进行物理化学改性。由然后进行阴离子表面活性剂有机改性。由于在
于APT的阳离子可交换性和富含硅羟基,用阳离APT表面先包覆金属氧化物后有机化涉及到二步
子或非离子表面活性剂和偶联剂进行有机化改性反应,因此,本文采用阴离子表面活性剂油酸钠
为改性剂。通过调节悬浮液pH值,探讨了油酸钠
收稿日期:2011-02-15
作者简介:徐继香(1982-),女,博士,研究方向为四凸棒黏土
用量、pH值和反应温度对APT有机化程度的影
改性
响;同时,通过红外光谱、流变和电位的测定,