Multifunctional colloidal nanoparticles which exhibit fluorescence, superparamagnetism, and thermosensitivity are produced by two step seed emulsifier-free emulsion polymerization in the presence of oleic acid (OA) and sodium undecylenate (NaUA) modified Fe(3)O(4) nanoparticles. In the first step, St and NIPAM polymerize the NaUA on the surface of Fe(3)O(4) nanoparticles to form Fe(3)O(4)/poly(...

Thermoresponsive colloidal particles were prepared by seeded precipitation polymerization of N-isopropylacrylamide (NIPAM) in the presence of a crosslinking monomer, N,N-methylenebisacrylamide (MBA), using polystyrene latex particles (ca. 50 nm in diameter) as seeds in aqueous dispersion. Phase transitions of the prepared poly(N-isopropylacrylamide), PNIPAM, shells on polystyrene cores were stu...

N-Isopropyl acrylamide (NIPAM), N,N-dimethyl acrylamide (DMAA), and 2-acetamidoethyl acrylate (AcAMEA) were copolymerized with ethylene employing [(P^O)PdMe(DMSO)] (1-DMSO; P^O = κ(2)-P,O-Ar(2)PC(6)H(4)SO(2)O with Ar = 2-MeOC(6)H(4)) as a catalyst precursor. Inhibition studies with nonpolymerizable polar additives show that reversible κ-O-coordination of free amide retards polymerization signif...

Nitrite contaminants in freshwater streams, resulting from run-off of fertilizers and livestock farming, are a major ecological challenge. Here, we have developed new family catalysts based on Pd/Al2O3 coated with N-isopropylacrylamide polymer (p-NIPAM) brushes that increase N-N bond formation over N-H formation, promoting nitrogen selectivity by 3-fold, reaching >99% for the containing 20 wt% ...

A series of Pd/Al2O3 catalysts coated with N-isopropylacrylamide polymer (p-NIPAM) brushes increasing particle size the support were prepared to study interplay between mass transport limitations and ability thermo-responsive modify reactivity during reaction. Nitrite hydrogenation in water was chosen as probe reaction, which is a key step reduction nitrites nitrates from drinking water. The re...

We have performed small angle neutron scattering measurements (SANS) on dilute aqueous dispersions of polymer microgel particles as a function of temperature, T . The microgel particles are spherical crosslinked assemblies of a loose gel network of a poly-N-isopropylacrylamide (NIPAM) polymer. When the temperature is raised beyond a critical temperature, T(lc) approximately 32 degrees C , the p...

This work has two objectives in the investigation of polymer solution lower critical solution temperature (LCST): First, to develop a new instrument to monitor LCST onset during copolymer synthesis by coupling several thermostatted light scattering flow cells to the output stream of an ACOMP system (Automatic Continuous Online Monitoring of Polymerization reactions). Second, to use this to inve...

The aim of the present work is the use of a water soluble enzyme in an organic solvent, still with a pronounced catalytic activity. Therefore, lipase B from Candida antarctica (CalB) is immobilized within micron-sized thermosensitive p-NIPAM hydrogel particles using a solvent exchange from polar to organic solvents. The absorbed amount of CalB is investigated at different immobilization tempera...

Thin polymer films are important in many areas of biomaterials research, biomedical devices, and biological sensors. The accurate in situ measurement of multiple physicochemical properties of thin polymer films is critical in understanding biocompatibility, polymer function, and performance. In this work we demonstrate a facile spectroscopic methodology for accurately measuring the micro-polari...