Nanoparticles by ROMP in Nonaqueous Emulsions

Abstract

The use of nonaqueous emulsions to synthesize particles by ROMP is described. The applied emulsions – consisting of two immiscible, organic, aprotic solvents – are versatile reaction systems for the preparation of polymer particles from moisture sensitive monomers and catalysts. Whereas up to now only polycondensations or polyadditions have been utilized in nonaqueous emulsions, catalytic polymerizations are now presented. Four different functionalized norbornene derivatives were applied for ROMP by a second‐generation Grubbs catalyst to form polymer nanoparticles. Furthermore, core/shell and surface functionalized nanoparticles applicable to “click” reactions were prepared to demonstrate the use of different polymerization procedures in one pot.magnified image

Block copolymers as polymeric stabilizers in non‐aqueous emulsion polymerization

“…In the last step, solvent evaporation also leads to polymer particles which are surface modified by the initially present block or graft copolymer. This type of approach was recently described in detail by Klapper, Müller et al 55–60, 62 for polymerization reactions involving water‐sensitive monomers or catalysts.…”

“…These emulsions are stabilized with tailor‐made A–B diblock copolymers, as for instance PI‐ block ‐PMMA or PS‐ block ‐PMMA, where the A and B blocks are selectively soluble in the solvents S 1 and S 2 respectively. In confirmation of Periard et al 's early results1, 2 mention can be made that the block copolymers used by Klapper, Müllen and co‐workers55–60 are of relatively high molecular weight, typically up to 60 000 g mol −1 , and that the particle size of the droplets decreases with increasing block copolymer concentration.…”

“…For the last 5 years, the major developments in this area are definitely those of Klapper, Müllen and their research group. In a series of publications, including a review article, these authors demonstrated in detail the possibilities and advantages of various polymerization processes in oil‐in‐oil emulsions used as nanoreactors for water‐sensitive monomers and catalytic systems 29, 55–60, 62. A large range of original polymer dispersions and new materials could thus be obtained.…”

Characterization of large molecular weight ester‐functionalized norbornene and hydroxylated norbornane carboxylic acid polymers prepared by ring‐opening metathesis polymerization

“…Doubly polymerizable polynorbornenes have been synthesized for use in photolithography 4. ROMP has also been used in the synthesis of polynorbornene nanoparticles5 and glycopolymers 6,7. It is also used to synthesize polymers for medical uses,8,9 including drug delivery10 and antibacterial agents 11.…”

Nonaqueous and Aqueous Emulsion ROMP Reactions Induced by Environment-Friendly Latent Ruthenium Indenylidene Catalyst Bearing Morpholine Substituted Bidentate (N, O) Schiff Bases

“…Perfluorinated solvent/hydrocarbons were used by the same research group in metallocene catalyzed propene polymerization . In 2010, Wagener and co‐workers have employed ROMP reactions to nonaqueous emulsion system using binary solvent system ( n ‐hexane/DMF) in the presence of Grubbs second generation catalyst …”