Chang Jeong Ho, Pyo Chae Eun
Korea Institute of Ceramic Engineering and Technology, Jinju, Gyeongnam 52851, Korea.
ACS Omega. 2022 Jul 22;7(30):26661-26669. doi: 10.1021/acsomega.2c02918. eCollection 2022 Aug 2.
This work reports a comparison of hydrophobic surface modification on mesoporous silica particles (MSPs) obtained by large-scale production using a batch reactor with linear and branched fluorinated and nonfluorinated silanes. Fluorinated silanes were used with TDF-TMOS and TFP-TMOS as a linear and branched structure, respectively. Nonfluorinated silanes were used with OD-TEOS and HMDS as a linear and branched structure, respectively. These four silanes were grafted on the surface of the MSPs as the function of the concentrations, and then, the water contact angles (WCAs) were measured. The WCA of the four silane-grafted MSPs was higher in the branch-structured silanes, namely, TFP-TMOS@MSPs and HMDS@MSPs than in linear-structured silanes, namely, TDF-TMOS and OD-TEOS due to the higher hydrophobicity by a lot of -F and -CH groups. Furthermore, the relationship between the WCA and BET parameters was demonstrated using the surface areas, pore volumes, and grafted amounts of the four silane-grafted MSPs. The structural characterization was demonstrated by solid-state Si MAS NMR to determine the bonding environment of Si atoms between the grafted silane and the surfaces of MSPs using the / and / ratios of the fluorinated and nonfluorinated silane-grafted MSPs. Among the four silanes, nonfluorinated HMDS@MSPs had a high contact angle of 135° as fluorinated TFP-TMOS@MSPs. When 5 wt % of HMDS@MSPs mixed with gravure ink was coated on a biodegradable polylactic acid (PLA) film, the contact angle was improved to 131.8 from 83.3° of the natural PLA film.
这项工作报告了通过间歇式反应器大规模生产获得的介孔二氧化硅颗粒（MSP）上，使用线性和支化的氟化及非氟化硅烷进行疏水表面改性的比较。分别使用TDF-TMOS和TFP-TMOS作为线性和支化结构的氟化硅烷。分别使用OD-TEOS和HMDS作为线性和支化结构的非氟化硅烷。这四种硅烷作为浓度的函数接枝到MSP表面，然后测量水接触角（WCA）。四种硅烷接枝的MSP的WCA在支化结构的硅烷（即TFP-TMOS@MSP和HMDS@MSP）中比在线性结构的硅烷（即TDF-TMOS和OD-TEOS）中更高，这是由于大量的-F和-CH基团导致更高的疏水性。此外，使用四种硅烷接枝的MSP的表面积、孔体积和接枝量证明了WCA与BET参数之间的关系。通过固态Si MAS NMR进行结构表征，以使用氟化和非氟化硅烷接枝的MSP的 / 和 / 比率确定接枝硅烷与MSP表面之间Si原子的键合环境。在这四种硅烷中，非氟化的HMDS@MSP与氟化的TFP-TMOS@MSP具有135°的高接触角。当将5 wt%的HMDS@MSP与凹版油墨混合涂覆在可生物降解的聚乳酸（PLA）薄膜上时，接触角从天然PLA薄膜的83.3°提高到131.8°。
