纳米二氧化硅粒径尺寸调控及其对表面化学修饰的影响研究  

Regulation of Nano SiO2 and the Effect of Particle Size on Surface Modification

作　　者：杨威 徐本梁 严顺洪 肖立鲜 YANG Wei;XU Benliang;YAN Shunhong;XIAO Lixian(China 19 th Metallurgical Chengdu Construction Co.,Ltd.,Chengdu 610073,China)

机构地区：[1]十九冶成都建设有限公司,成都610073

出　　处：《硅酸盐通报》2020年第7期2321-2325,共5页Bulletin of the Chinese Ceramic Society

摘　　要：本文通过sol-gel法制备了粒径可控的纳米SiO2,最小粒径为35 nm,最大粒径为350 nm。采用比表面积测试仪、透射电镜(TEM)、扫描电镜(SEM)以及红外光谱(FTIR)表征了纳米SiO2的物理化学特性,研究了不同粒径纳米SiO2对其表面化学修饰的影响机制。结果表明,sol-gel法制备纳米SiO2用水量显著影响粒径尺寸,粒径小于80 nm时,SiO2表面呈粗糙和不规则球形。粒径小于80 nm的SiO2表面的羟基主要以孤立的羟基存在,而粒径大于180 nm时,其表面的羟基以氢键结合的状态为主。纳米SiO2表面的羟基结合状态决定了其表面与硅氧烷化学反应活性,氢键结合的羟基基团不利于硅氧烷的化学修饰,孤立存在的羟基基团有利于纳米SiO2与硅氧烷反应。这一研究结果对指导纳米二氧化硅的表面处理和化学修饰具有重要意义。In this paper,nano SiO2 with regulated particle size ranging from 35 nm to 350 nm was prepared by sol-gel method.Specific surface area spectrometer(BET),transmission electron microscopy(TEM),scanning electron microscopy(SEM)and infrared spectroscopy(FTIR)were used to characterize the physical and chemical properties of nano SiO2.The results show that the amount of water used to prepare nano SiO2 by sol-gel method significantly affects the particle size.When the particle size is less than 80 nm,the surface of SiO2 is rough and irregular,in which case the hydroxyl groups on SiO2 surface remain isolated,while the hydroxyl groups on the surface of SiO2 larger than 180 nm are mainly hydrogen bonded.It is indicated that the combined state of hydroxyl groups on nano-silica determines its surface reactivity with siloxane.Hydrogen bonding of hydroxyl groups impairs siloxane chemical modification,and the hydroxyl groups of isolated state benefit surface reaction with siloxane.This study is great significance for direction of surface treatment and chemical modification of nano-silica.

关 键 词：纳米SIO2 尺寸调控 羟基基团 化学修饰 

分 类 号：TQ127.2[化学工程—无机化工]