摘要
纳米TiO2等无机粒子在水相介质中极易发生团聚,进而会严重影响其功效的充分发挥。本文考察了TiO2水分散液体系中TiO2粒子的团聚形式,比较了几种常规分散技术以及表面锚固改性技术对这些团聚体的解团聚效果。结果发现:大部分TiO2粒子在水相介质中以软团聚体形式存在,高速剪切和添加分散剂对这些软团聚体的解团聚作用有限,超声分散可产生暂时性的解团聚效应,但随着超声场的去除,被分散的TiO2粒子又会再次逐渐聚集。TiO2粒子表面的聚合物原位锚固改性可改变其表面性质,因而对软团聚体具有更为高效稳定的解团聚作用,从而可明显提高复合粒子中的TiO2粒子在水相介质和目标织物表面的分散性和分散稳定性。
Nanoparticles, such as TiO2, are readily aggregated in aqueous medium, which always drastically deteriorates their performance. In this study, the agglomeration state of TiO2 particles in aqueous dispersion and the effects of several conventional dispersion technologies and surface grafting modification technology on the de-aggregation of TiO2 agglomeration were investigated. It was found that most of TiO2 particles in aqueous media existed as soft agglomeration. The de-aggregation effects of highspeed shear dispersion and dispersing agent on the soft agglomeration were not obvious, and the ultrasonic dispersion could only have a temporary de-aggregation effect. While the surface of TiO2 particles was grafting modified by polymer molecule via in-situ polymerization, an extensive de-aggregation effect with good efficiency and stability could be achieved. Thus the dispersion and the dispersion stability of TiO2 particle in aqueous media as well as in the fabric surface could be significantly improved.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2009年第12期3159-3164,共6页
CIESC Journal
基金
国家自然科学基金项目(50803058)
长江学者和创新团队发展计划项目(IRT0654)
教育部留学回国人员科研启动基金项目(2008890)
浙江省科研计划项目(2009C31089)
浙江省新苗人才计划项目(2008R40G2060040)~~
关键词
纳米TIO2
软团聚体
解团聚
锚固改性
nano-TiO2
soft agglomeration
de-aggregation
anchoring modification
