In this study, a series of polyetherimide/SBA-15: 2-D hexagonal P6mm, Santa Barbara USA (PEI/SBA-15) adsorbents modified by phosphoric ester based surfactants (including tri(2-ethylhexyl) phosphate (TEP), bis(2-ethylhexyl) phosphate (BEP) and trimethyl phosphonoacetate (TMPA)) were prepared for CO 2 adsorption. Experimental results indicated that the addition of TEP and BEP had positive effects on CO 2 adsorption capacity over PEI/SBA-15. In particular, the CO 2 adsorption amount could be improved by around 20% for 45PEI–5TEP/SBA-15 compared to the additive-free adsorbent. This could be attributed to the decrease of CO 2 diffusion resistance in the PEI bulk network due to the interactions between TEP and loaded PEI molecules, which was further confirmed by adsorption kinetics results. In addition, it was also found that the cyclic performance of the TEP-modified adsorbent was better than the surfactant-free one. This could be due to two main reasons, based on the results of in situ DRIFT and TG-DSC tests. First and more importantly, adsorbed CO 2 species could be desorbed more rapidly over TEP-modified adsorbent during the thermal desorption process. Furthermore, the enhanced thermal stability after TEP addition ensured lower degradation of amine groups during adsorption/desorption cycles.
Neng Ye,Junchi Zheng,Xin Ye,Jiajia Xue,Dongli Han,Haoshu Xu,Zhao Wang,Liqun Zhang
Nano-silica is an important component for producing elastomer composites used for fabricating “green tires.” However, the poor dispersion of silica particles in the rubber matrix and the emission of volatile organic compounds (VOCs) during the silica modification limit the applications of the modifiers. Here, bis-epoxypropyl polysulfide (BEP), a novel epoxy-type coupling agent, was designed and synthesized for nano-silica modification to cause an interfacial interaction between nano-silica and the rubber matrix and avoid VOC emission. The thermogravimetric analysis result and the bound rubber content show that BEP effectively built a bridge between the nano-silica and the rubber, which led to a strong interfacial effect and promising mechanical performance characteristics. The silica dispersion in solution-polymerized styrene-butadiene rubber (SSBR) was studied using a transmission electron microscope and a rubber process analyzer, and the results demonstrate that BEP could significantly improve silica dispersion. The static and dynamic mechanical performance results indicate that BEP is a valid coupling agent that can achieve silica/SSBR composites with high moduli and reinforcement indices. Moreover, the combination of BEP and bis-(γ-triethoxysilylpropyl)-tetrasulfide (TESPT) was also found to demonstrate a synergistic effect , which resulted in excellent static and dynamic performances of silica/SSBR composites for preparing higher-energy-efficient “green tires.”
危险品化学品经营许可证（带存储）