Hollow polymer particles with nanoscale pores and reactive groups on their rigid shells: preparation and application as nanoreactors.

A novel type of hollow polymeric particles was prepared according to a strategy consisting of three major steps: the synthesis of template particles (PMV) based on maleic anhydride/vinyl acetate; the formation of core/shell particles by using maleic anhydride/divinylbenzene as comonomers, AIBN as initiator, and PMV as templates; and the removal of the core by dissolving it with an organic solvent. This route gave rise to core/shell and hollow particles in high yields, and the as-prepared particles possessed obvious advantages. The size of the core and the thickness of the shell were controllable by adjusting the reaction conditions. The shells were of high rigidity and strength as a result of the high cross-linking degree. The surface anhydride groups offered a platform for various postfunctionalization reactions of the particles. The nanoscale pores in the shells enabled an encapsulation of target compounds. The as-prepared hollow particles could be applied as "nanoreactors". To attest to this concept, Ag-encapsulated composite particles were further prepared via redox reactions between NaBH(4) and AgNO(3) inside the hollow particles. A mechanism for the formation of core/shell particles and pores in the shells is proposed.