Quantitative measurement of physisorbed silane on a silica particle surface treated with silane coupling agents by thermogravimetric analysis

Abstract

We investigated a new method for estimating the amount of silanes physisorbed on a silica particle surface treated with silane coupling agents from a weight loss curve measured by thermogravimetric (TG) analysis. The silica particles were treated with 3-glycidoxypropyl trimethoxysilane (GPTMS) or 3-mercaptopropyl trimethoxysilane (MrPTMS) with both dry and wet treatment methods. In the TG curve for silica particles treated with GPTMS, the weight decreased in three steps: 100-1708C (first step), 170-2508C (second step), and 250-4008C (third step). The weight loss in the first step decreased with heating or acetone washing to remove the physisorbed molecules as the posttreatment. The three weight losses were found to be based on physisorbed monomeric silanes (first step), physisorbed polycondensed silanes (second step), and chemisorbed silanes (third step), respectively. The amount of physisorbed silanes on the silane-treated layer could be estimated from the TG curve without solvent washing to remove the physisorbed molecules. The amounts obtained were almost equal to those measured from a comparison of the weight losses for the treated particles before and after acetone washing. A similar tendency was observed for MrPTMS-treated silica. Thus, the amount of physisorbed silanes in silane-coupling-agent-treated silica particles was successfully estimated from the TG measurements. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43256.

Surface Modification of a MXene by an Aminosilane Coupling Agent

“…Overall, the TGA results here are consistent with reports on GLYMO‐TiO 2 , APTES‐SiO 2 , and other surface functionalized nanoparticles, in which three weight loss steps exist in the 25–500 °C range. Yamazaki et al attributed the three weight loss steps to physiosorbed monomeric silanes, physiosorbed polycondensated silanes, and chemisorbed silanes .…”

“…Overall, the TGA results here are consistent with reports on GLYMO‐TiO 2 , APTES‐SiO 2 , and other surface functionalized nanoparticles, in which three weight loss steps exist in the 25–500 °C range. Yamazaki et al attributed the three weight loss steps to physiosorbed monomeric silanes, physiosorbed polycondensated silanes, and chemisorbed silanes . Salon et al indicated that compared to silane coupling agents with other functional groups, those based on amino groups exhibit fast polycondensation kinetics, hence the expected large second weight loss step .…”

Research on Payne effect of natural rubber reinforced by graft‐modified silica

“…Secondly, the nano‐silica showed small size and high surface energy, which was prone to aggregation, and thus leading to a significant decrease of the processing performance and reinforcing properties when it was used to rubber reinforcement. So far, researchers had proposed some surface modification methods, including surfactant modification, silane coupling agent modification, graft polymer modification and so on, to improve the dispersion of silica and the compatibility in the polymer matrix. These methods played a good role in improving the reinforcing properties of silica.…”

“…However, the current research works focused on the choice of appropriate modifier and modification processes . There were few studies on the mechanism of silica ‐ reinforced rubber, such as Payne effect mechanism.…”

Application of Laser Ionization Time-of-Flight Mass Spectrometry for the Direct Measurement of a Silane Coupling Agent in Slurries

“…2 In general, unreacted organic compounds for surface coating are then removed from a slurry by washing. Several analytical techniques are applied to evaluate metal oxide nanoparticles modified with organic compounds, which amounts to thermogravimetric (TG) analysis of the weight of organic coatings [3][4][5] and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy for the analysis of interactions between organic compounds and metal oxides. [5][6][7][8] On the other hand, information directly obtained from slurries, such as viscosity of a slurry 9 and the diameter of particles, 10 is limited at present.…”