A facile route to bespoke macro- and mesoporous block copolymer microparticles

Abstract

A facile and versatile strategy to fabricate macro- and mesoporous block copolymer microparticles with bespoke characteristics using supercritical CO2.

In situcrosslinking of nanostructured block copolymer microparticles in supercritical carbon dioxide

“…33 Previously, we reported RAFT controlled dispersion polymerisation in scCO 2 as a unique and facile route to create multigram quantities of nanostructured microparticulate BCPs. 14,34,35 Moreover, we have also demonstrated that the sizes of the microparticles can be controlled reproducibly from 300 nm through to 5 μm. 36 Very recently, we developed a facile and versatile approach to convert these nanostructured microparticles into porous microparticles via swelling/deswelling.…”

“…The swelling process of the PMMA-b-P4VP BCP microparticles in ethanol followed our earlier published procedures. 34 The original BCP microparticles (50 mg) were fully dispersed in alcohol (3 ml) in a glass vial (3.5 ml) and shaken 3 times by hand over a two-hour period. The particles were then left standing until they settled to the bottom of the vial.…”

“…This is then followed by the addition of DVB in conjunction with the remaining 4VP (Scheme 1). In our recent study, 34 we determined that the polymerisation induced microphase separation begins when P4VP = ~5 kDa when the first PMMA-block has a length of ~50 kDa (i.e. ~9 mol% P4VP).…”

“…36 Very recently, we developed a facile and versatile approach to convert these nanostructured microparticles into porous microparticles via swelling/deswelling. 34 It was demonstrated that the porosity can be tailored over a wide size range from 20 to 200 nm, and diverse morphologies from isolated spherical pores, short porous channels, to interpenetrated pore networks, could be achieved by adjusting the block ratio and block length. However, in order to further exploit these materials for applications such as drug delivery, chromatographic columns, and as templates for inorganic materials, etc., it is important to consider that the particle structures and/or scaffolds can be susceptible to collapse in the presence of organic solvents.…”

Clean Block Copolymer Microparticles from Supercritical CO2: Universal Templates for the Facile and Scalable Fabrication of Hierarchical Mesostructured Metal Oxides

“…12 -200 nm have already been achieved in BPC microparticles of PMMA-b-P4VP by altering the molecular weight of the two blocks. 31 Furthermore, the templated synthesis of other BCP morphologies (e.g. lamellar, etc.)…”