Charged microcapsules for controlled release of hydrophobic actives. Part 1: encapsulation methodology and interfacial properties
Artikel i vetenskaplig tidskrift, 2013

Highly charged microcapsules have been prepared using the internal phase separation technique. The charges are introduced by using ionic dispersants, which have been characterized with respect to surface activity with a quartz crystal microbalance with dissipation monitoring and with optical tensiometry. The long-term stability of the microcapsule suspension without excess dispersant, as well as the stability at high ionic strength, have been investigated. Three types of ionic dispersants have been evaluated: a weak polyacid (poly(methacrylic acid)), a small set of ionic amphiphilic block copolymers of poly(methyl methacrylate)-block-poly(sodium (meth) acrylate) type and an oil-soluble anionic surfactant, sodium 1,5-dioxo-1,5-bis(3,5,5-trimethylhexyloxy)-3-((3,5,5-trimethylhexyloxy)carbonyl)pentane-2-sulfonate, in combination with a water-soluble polycation, poly(diallyldimethylammonium chloride). The block copolymer based microcapsule suspension is characterized by a long-term stability, even at high ionic strength, provided by electrostatic and steric stabilization. The weak polyacid based microcapsule suspension is stable for a few weeks, after which aggregation starts due to desorption of the dispersant. The surfactant-polycation based microcapsules appear to have a multicore morphology in contrast to the weak polyacid or block copolymer based microcapsules, which are core-shell particles.

Författare

Markus Andersson Trojer

SuMo Biomaterials

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Ye Li

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Christoffer Abrahamsson

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

SuMo Biomaterials

A. Mohamed

University of Bristol

J. Eastoe

University of Bristol

Krister Holmberg

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Magnus Nydén

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

SuMo Biomaterials

Soft Matter

1744-683X (ISSN) 1744-6848 (eISSN)

Vol. 9 5 1468-1477

Ämneskategorier

Annan kemiteknik

Annan kemi

Styrkeområden

Materialvetenskap

DOI

10.1039/c2sm27275j