Preparation of magnetic latex particles by emulsion polymerization of styrene in the presence of a ferrofluid

Abstract

SYNOPSISMagnetic latex particles were prepared by the emulsion polymerization of styrene at 70°C in the presence of a commercial ferrofluid containing surfactant-stabilized magnetite particles in the aqueous phase or its modification by ultrafiltration, using potassium persulfate as an initiator. The effects of diversified variables such as the amounts of initiator, monomer, and additive (calcium chloride and fluorescent dyes) on the polymerization reaction and particle characteristics were investigated. The general polymerization features were analogous to those of ordinary emulsion polymerizations. Transmission electron microscopy revealed that when the commercial ferrofluid was used the magnetite particles localized in the latex particles and the magnetite content varied from particle to particle and that when the ferrofluid was used after ultrafiltration the magnetite particles were dispersed well in the latex particles.

A mechanistic investigation of Pickering emulsion polymerization

“…The use of water as continuous phase has environmental benefits, and the dual nature of these particles allows for performance enhancement of application products such as coatings and adhesives. For instance, hybrid particles can add magnetic response [1][2][3] and improve flame retardant and mechanical properties of dried films. 4,5 Furthermore, poly(lauryl acrylate) latex particles armoured with Laponite clay discs have been shown to increase the tack adhesion of pressure-sensitive adhesives, when used as additive.…”

Preparation and characterization of superparamagnetic chitosan microspheres: Application as a support for the immobilization of tyrosinase

“…8 These polymer particles have also been proposed as useful supports for the immobilization of enzymes because after the reaction they can be easily separated from the products with a magnet and collected for reuse. 9,10 Chitosan is a biocompatible, biodegradable, nontoxic, and mucoadhesive polymer, and this makes it attractive for applications in medicine and pharmacy. [11][12][13] These interesting characteristics have led to the development of numerous applications of chitosan and its derivatives in biomedicine, such as surgical sutures, 14 biodegradable sponges and bandages, [15][16][17] matrices in microspheres, microcapsules, membranes, and compressed tablets for the delivery of drugs, 18 -20 and orthopedic [21][22][23] and dentistry materials.…”

Multifunctional magnetic-responsive hydrogels to engineer tendon-to-bone interface

“…[14], [82], [118] Various assembling approaches have been used including microfluidics, nanotextured surfaces, and surface tension. [119], [120], [121] These techniques allow microtissues scale-up into larger tissues and permit the creation of complex and well-defined 3D-architectures.…”

“…[76] Diverse templates of smart magnetic materials from spheres, liposomes, gels to 3D hierarchical structures have been explored for TERM strategies (Figure 1.3). [28], [82], [83], [84] MNPs can be integrated within 3D scaffolds directly or by previous association with (stem) cells ( Figure 1.3E). [85] After incorporation, the application of an external magnetic field may induce scaffold structure deformation.…”