Graft Copolymerization of Methyl Methacrylate onto Casein Initiated by Potassium Ditelluratocuprate(III)

Abstract

A novel redox system, potassium ditelluratocuprate(III) (DTC)-casein was employed to initiate graft copolymerization of methyl methacrylate (MMA) onto casein in an aqueous alkali solution medium. The effects monomer concentration, initiator concentration, pH, temperature, and time were investigated. The grafting conditions were optimized by means of a series of copolymerization. The DTC -casein system was found to be an efficient redox initiator for this graft copolymerization. The structures and thermal stability of casein and casein-g-PMA were characterized by infrared spectroscopy (IR), thermogravimetric analysis (TGA), and scanning electron microscope (SEM). A mechanism is proposed to explain the formation of radicals and the initiation.

Structural and Thermal Investigations of Biomimetically Grown Casein–Soy Hybrid Protein Fibers

“…Broad peak at 3,300 cm −1 may be due to the O-H or N-H stretching vibration. These assignments are in agreement with those reported earlier for casein and soy protein materials [16,22,25]. The FT-IR spectra of hybrid protein fibers are relatively similar compared to that of neat casein and soy fibers.…”

Preparation and characterization of homogeneous and enhanced casein protein-based composite films via incorporating cellulose microgel

“…Although vinyl monomers (e.g. methyl methacrylate, butyl acrylate, and caprolactam) 7–9 , crosslinking agent 10–13 or polyurethane 14,15 have been grafted to the α-C or N of casein structure, which can introduce new components and block some hydrophilic groups of casein structure, resulting in high hydrophobicity and mechanical tensile strength and elasticity of the casein films. However, it involves harsh reaction conditions and environmental concerns.…”

Proteins as Promising Biobased Building Blocks for Preparing Functional Hybrid Protein/Synthetic Polymer Nanoparticles

“…Moreover, a typical kinetic behavior for radical polymerization confined in a preformed microenvironment was observed, which is in agreement with a radical polymerization mechanism involving complexes between the polymer and MMA on copper ion. 96 A redox initiation approach was followed elsewhere to efficiently graft BA 97 and MMA 98 Moreover, another novel synthetic method to create casein/ polymer amphiphilic nanoparticles and overcome such oxidative problems of persulfate initiators was developed in the later works of Li and co-workers 79,99 It consists of an EF-EP in which an organic hydroperoxide (ROOH) initiator, such as tert-butyl hydroperoxide (TBHP), reacts with the amino groups present in casein, generating radicals in their N atoms. 79 The radicals formed onto casein amine groups initiate the graft copolymerization of MMA, and as these radicals become water insoluble they assemble into polymer NPs precursors.…”

“…Moreover, a typical kinetic behavior for radical polymerization confined in a preformed microenvironment was observed, which is in agreement with a radical polymerization mechanism involving complexes between the polymer and MMA on copper ion. 96 A redox initiation approach was followed elsewhere to efficiently graft BA 97 and MMA 98 onto casein, using potassium diperiodatonickelate (Ni(IV)), and potassium ditelluratocuprate(III) (DTC), respectively, which form redox systems with casein.…”