Functionalization-Induced Self-Assembly of Polystyrene/Kaolinite in Situ Nanocomposites into Giant Vesicles

Abstract

We report a facile functionalization strategy for fabrication of giant, inorganic–polymer hybrid vesicles by controlled aminosilyl/vinylsilyl functionalization (AS/VS) of the aluminol layer in kaolinite (Kaol) by intercalation and subsequent polymerization of styrene with the in situ polystyrene clay nanocomposite (PCN), followed by self-assembly in solvents. The synergistic effect of the AS/VS ratio on functionalization-assisted intercalation of Kaol was established in 1:3AS/VS-Kaol by the greater extent of formation of higher interlayer spacing corresponding to 1.12 nm compared to 1:1AS/VS-Kaol. As the AS/VS ratio was increased, the PCN synthesized showed an increase in molecular weight attributed to higher vinyl functionalization of Kaol. The PCN, 1:3AS/VS-Kaol/PS, showed self-assembly in tetrahydrofuran at 2.5 mg mL–1 into giant vesicles of 2–6 μm diameter with a wall thickness of 300–400 nm. This result is attributed to the functionalization-induced molecular mass-directed bilayer assembly of the delaminated, Janus-type, modified Kaol in a polar aprotic solvent by end-to-end hydrogen bonding involving terminal −OH groups along the wall and −NH2 groups laterally and further stabilized by the π–π interactions of the phenyl moiety along the periphery. Rhodamine-loaded vesicles showed a controlled release in buffer solutions of pH 7.0 and 9.0, attributed to the amino group-assisted pore formation. In a buffer solution of pH 4.0, rapid release of the dye was observed because of the collapse of the vesicle directed by protonation of the amino group. This study forms the first report on a novel method for the synthesis of rigid vesicles by functionalization-induced self-assembly of Kaol-based in situ PCN for possible applications in the cost-effective controlled delivery of drugs or cosmetics for topical applications.

Functionalization and metathesis polymerization induced self-assembly of an alternating copolymer into giant vesicles

“…4f with some of this coalescence being sufficiently energetic relief. 23 These materials of micelles and vesicles can be further utilized to obtain a series of porous nanostructures with tailored sizes and shapes and further loaded with metal catalyst to realize catalytic applications.…”

Inorganic material-based Janus nanosheets: asymmetrically functionalized 2D-inorganic nanomaterials

“…[92][93][94][95][96] In methoxy-modified kaolinite whose aluminol surface was regioselective and partially modified with methanol, the aluminol surface was further modified with a mixture of APTES and trimethoxyvinylsilane. 97 This organically modified kaolinite consisted of stacked Janus nanosheets bearing both an APTES moiety and a vinyl moiety on one side. A polymer composite with kaolinite-based Janus nanosheets was Na + , respectively.…”

Natural and synthetic functional materials for broad spectrum applications in antimicrobials, antivirals and cosmetics

“…The easiest functionalization strategy reported in which inorganic‐polymer hybrid vehicles were fabricated. One of such examples is aminosilyl/vinylsiyl controlled functionalization where aluminol layer of kaoliniteb (kaol) self‐assembled in solvent 72 …”