Poly(divinylbenzene-55)[poly(DVB-55] microspheres were used as building blocks to form polymer capsule walls consisting of interconnected microspheres. The microspheres had to be surface-functionalized with maleic acid to facilitate their interfacial assembly. In addition, porous and functionalized poly(DVB-55) microspheres were embedded across interfacial polyurea capsule membranes to form composite tectocapsules where release of core materials is designed to occur through the microsphere pores, rather than by conventional wall diffusion. Electron microscopy and X-ray spectromicroscopy were used to characterize the wall compositions, and release data are presented to illustrate the role of microspheres acting as release portals.
Membrane Solubilization by Styrene-Maleic Acid Copolymers: Delineating the Role of Polymer Length
