水解法制备SiO2包裹γ-Ce2S3色料及其耐酸性研究

Study on the Preparation and Acid Resistance of Silica Coated γ-Ce_2S_3 Pigments by Hydrolysis Method

本文以市售大红色料γ-Ce_2S_3为原料,正硅酸乙酯(TEOS)为硅源,采用水解法制备了SiO_2包裹γ-Ce_2S_3色料,采用X射线衍射(XRD)、透射电子显微镜(TEM)、扫描电镜(FE-SEM)、能谱仪(EDS)、傅立叶红外光谱(FTIR)等技术对色料进行了表征。研究结果表明,在TEOS/H_2O质量比为1∶20、Ce/Si摩尔比为3∶1、水解温度为45℃、水解用纯水滴加速率为0. 3 m L/min的条件下,可获得均匀致密的无定型二氧化硅(Si O2·x H2O)包裹层,其厚度为100 nm左右,包裹色料仍保持鲜艳的红色,其色度L*、a*和b*值分别为26. 82、35. 53和29. 60;该条件下所得包裹色料的耐酸性最佳,未包裹色料浸泡于1 mol/L的盐酸中半分钟之内已失去红色,而该色料浸泡2 h其呈色仍没有明显变化。

Silica coatedγ-Ce 2S 3 red pigments were successfully prepared by hydrolysis method using purchasedγ-Ce 2S 3 as raw material and tetraethoxysilane(TEOS)as silicon source.The as-obtained pigments were characterized by XRD,TEM,FE-SEM,EDS and FT-IR.The results show that the uniform and dense amorphous silica(SiO 2·x H 2O)coating layer with the thickness of about 100 nm was formed on the surface of theγ-Ce 2S 3 particles under the weight ration of 1∶20(TEOS to H 2O),the mole ration of 3∶1(Ce to Si),dripping rate of 0.3 mL/min(deionized water)and hydrolysis temperature of 45℃.The coated pigments could still maintain the nature of bright red,and the values of L*,a*and b*were 26.82,35.53 and 29.60 respectively.The color of the coated pigments prepared under this condition did not change obviously after immersing in 1 mol/L hydrochloric for 2 h while the color of the uncoated pigments fade in half a minute under the same condition,showing that the coated pigments had better acid resistance.