Steinbacher Jeremy L, Moy Rebecca W Y, Price Kristin E, Cummings Meredith A, Roychowdhury Chandrani, Buffy Jarrod J, Olbricht William L, Haaf Michael, McQuade D Tyler
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301, USA.
J Am Chem Soc. 2006 Jul 26;128(29):9442-7. doi: 10.1021/ja0612403.
The preparation of hierarchically structured organosilicon microcapsules from commercially available starting materials is described. Using a microfluidic device, an emulsion of dichlorodiphenylsilane is formed in a continuous phase of aqueous glycerol. The silane droplets undergo hydrolysis, condensation, and crystallization within minutes to form self-assembled, core-shell microcapsules. The microparticles have been characterized with light and electron microscopy, nuclear magnetic resonance spectroscopy (NMR), diffusion-ordered NMR spectroscopy (DOSY), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffraction (XRD). The characterization data show that the microcapsule walls consist of amorphous, oligomeric poly(diphenylsiloxane) surrounded by a spiny layer of crystalline diphenylsilanediol. Glycerol is occluded within the wall material but is not covalently bound to the silicon components. Glycerol is a crucial element for producing low-dispersity microcapsules with well-ordered surface spines, as the use of methyl cellulose as viscomodifier yields amorphous surfaces.
本文描述了由市售起始原料制备具有分级结构的有机硅微胶囊的方法。使用微流控装置，在甘油水溶液的连续相中形成二氯二苯基硅烷乳液。硅烷液滴在几分钟内经历水解、缩合和结晶，形成自组装的核壳微胶囊。通过光学显微镜、电子显微镜、核磁共振光谱（NMR）、扩散有序核磁共振光谱（DOSY）、傅里叶变换红外光谱（FTIR）、差示扫描量热法（DSC）和粉末X射线衍射（XRD）对微粒进行了表征。表征数据表明，微胶囊壁由无定形的低聚聚（二苯基硅氧烷）组成，周围是结晶二苯基硅二醇的刺状层。甘油被包封在壁材料中，但未与硅组分共价结合。甘油是制备具有有序表面刺的低分散性微胶囊的关键元素，因为使用甲基纤维素作为粘度调节剂会产生无定形表面。
