Influences of VTMS/SiO2 ratios on the contact angle and morphology of modified super-hydrophobic silicon dioxide material by vinyl trimethoxy silane.

Autor: Wang, Chuang, Yang, Hui, Chen, Fei, Peng, Lei, Gao, Hong-fang, Zhao, Li-ping
Zdroj: Results in Physics; Sep2018, Vol. 10, p891-902, 12p
Abstrakt: Graphical abstract Highlights • Vinyl trimethoxy silane was in-situ grafted successfully onto the SiO 2 surface by chemical modification. • A uniform rough micro-nano-dual structure was achieved on the SiO 2 surface after modification. • An appropriate ratio of vinyl trimethoxy silane to SiO 2 was 10:1. • The static contact angle of modified SiO 2 reached the maximum value of 154° and the rolling angle was 4°. Abstract Vinyl trimethoxy silane (VTMS) was used as a modifier and strong ammonia was used as a pH regulator to prepare modified SiO 2 superhydrophobic composites. VTMS was successfully in-situ grafted onto the surface of SiO 2 via chemical modification. A contact angle detector, laser particle sizer, X-ray diffractometer, Fourier transform infrared spectroscope, scanning electron microscope, and thermogravimetric analyzer were employed to investigate the influence of the amount of VTMS on the hydrophobicity, crystal structure, surface microstructure, particle size, and grafting rate of the obtained SiO 2 composites. The results show that VTMS can modify SiO 2 within a short time to achieve superhydrophobic SiO 2 powder with an interesting dual microstructure. The VTMS/SiO 2 ratio has an obvious influence on the water contact angle and on the micro-double structure of the modified SiO 2 powder, while the reaction time and the drying time have little effect on them. When the VTMS/SiO 2 ratio was 10:1, the static contact angle of the modified SiO 2 reached the maximum value of 154° (greater than 150°), and the rolling angle of 4° (far less than 10°) was sufficiently small to meet the requirements of superhydrophobicity. The particle sizes of the modified nano-SiO 2 were distributed uniformly and the grafting rate of VTMS onto the SiO 2 surface was satisfied. [ABSTRACT FROM AUTHOR]
Databáze: Supplemental Index