ThoMSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas-UNICAMP Campinas, SP, Brazil.
Rapid Commun Mass Spectrom. 2010 Dec 15;24(23):3441-6. doi: 10.1002/rcm.4794.
The progress of an on-surface polymerization process involving alkyl and perfluoroalkyl silanes and siloxanes was monitored in real-time via easy ambient sonic spray ionization mass spectrometry (EASI-MS). When sprayed on surfaces, the organosilicon compounds present in commercially available nanofilm products (NFPs) react by condensation to form a polymeric coating. A NFP for coating of floor materials (NFP-1) and a second NFP for coating tiles and ceramics (NFP-2) were applied to glass, filter paper or cotton surfaces and the progress of the polymerization was monitored by slowly scanning the surface. Via EASI(+)-MS monitoring, significant changes in the composition of hydrolysates and condensates of 1H,1H,2H,2H-perfluorooctyl triisopropoxysilane (NFP-1) and hexadecyl triethoxysilane (NFP-2) were observed over time. The abundances of the hydrolyzed species decreased compared with those of the non-hydrolysed species for both NFP-1 and NFP-2 and the heavier oligomers became relatively more abundant over a period of 15-20 min. A similar tendency favouring the heavier oligomers was observed via EASI(-)-MS. This work illustrates the potential of ambient mass spectrometry for the direct monitoring of polymerization reactions on surfaces.
通过简单的环境声波喷雾电离质谱（EASI-MS）实时监测涉及烷基和全氟烷基硅烷和硅氧烷的表面聚合过程的进展。当喷洒在表面上时，商业上可用的纳米薄膜产品（NFPs）中存在的有机硅化合物通过缩合反应形成聚合涂层。一种用于地板材料涂层的 NFPs（NFP-1）和另一种用于瓷砖和陶瓷涂层的 NFPs（NFP-2）被施加到玻璃、滤纸或棉表面上，并通过缓慢扫描表面来监测聚合的进展。通过 EASI(+)-MS 监测，观察到 1H、1H、2H、2H-全氟辛基三异丙氧基硅烷（NFP-1）和十六烷基三乙氧基硅烷（NFP-2）的水解物和缩合物的组成随时间发生了显著变化。与未水解的物质相比，NFP-1 和 NFP-2 的水解物质的丰度降低，并且在 15-20 分钟的时间内，较重的低聚物变得相对更丰富。通过 EASI(-)-MS 观察到了类似的有利于较重低聚物的趋势。这项工作说明了环境质谱在表面聚合反应的直接监测中的潜力。
