The role of cobalt(II) complexes containing 2-formylpyrrolyl chelating ligands and phosphine ligands combined with a bromo-alkyl ester, an alkyl bromide or an azo compound in the formation of suitable initiator systems for vinyl monomer controlled radical polymerization was studied. The formation of syndiotactic-rich (Pr>0.7) poly(methyl methacrylate) (PMMA) and atactic (Pr=0.49) poly(styrene) ...

modification of natural polymers like protein by graft co-polymerization is an important method to incorporate the desired properties into the backbone. soy protein concentrate (spc) was grafted with ethylmethacrylate (ema) using ascorbic acid /potassium persulphate as redox initiator system under pressure. different reaction parameters such as reaction time, reaction pressure, solvent amount, ...

Using styrene as raw material, potassium persulfate as an initiator, beta-cyclodextrin as a stabilizer, polystyrene microspheres were successfully prepared with nice monodisperse feature by means of soap-free emulsion polymerization method. Experimental studies were performed in detail to check the effect of the synthesis process of the microspheres, the stabilizer dosage, monomer concentration...

The mechanical fracture of polymer produces polymeric free radical chain-ends, by which liner block copolymers have been synthesized. A diblock copolymer of microcrystalline cellulose (MCC) and poly 2-hydroxyethyl methacrylate (pHEMA) was produced by the mechanochemical polymerization under vacuum and room temperature. The fraction of pHEMA in MCC-block-pHEMA produced by the mechanochemical pol...

“A living race” – polymerization kinetics of anionic polymerizations depends strongly on the solvent polarity and reactivity of the growing chain end. Both the carband oxyanionic polymerization is under control at the university lab and on the industrial level, however, no information for the aza-anionic polymerization of aziridines has been reported systematically. This work studies the polyme...

Over the last decade versatile, electrostatic layer-by-layer (LbL) assembly methods involving polyelectrolytes have been widely used in the preparation of hollow capsules. These capsules can be fabricated by the stepwise adsorption of polyelectrolytes with charges that are opposite from their aqueous media onto templating cores, especially organic or inorganic particles and biopolymers, followe...

A novel approach was developed for the synthesis of tethered polymer layers with thickness and grafting density gradients. Poly(glycidyl methacrylate) (PGMA) was employed as a primary anchoring layer to attach the polymer chains to the surface of a silicon wafer. A linear temperature gradient heated stage was used for the generation of a gradual variation in the thickness of the anchoring PGMA ...

Environmentally responsive poly(N-isopropylacrylamide) brushes were grafted from the surface of polymer particles or flat surfaces in order to generate reversible hydrophilic and hydrophobic surfaces. The use of atom transfer radical polymerization was demonstrated for the grafting of polymer brushes as it allows efficient control on the amount of grafted polymer. The polymer particles were gen...