Design of modified plastic surfaces for antimicrobial applications: Impact of ionizing radiation on the physical and mechanical properties of polypropylene

Abstract

is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. Surface modification of polypropylene (PP) sheets was carried out by radiation induced graft polymerization of hydrophilic functional molecules such as N,N-dimethylacrylamide (DMA) and [2-methacryloyloxy)ethyl] trimethylammonium chloride, which is a quaternary ammonium salt (QAS). Polypropylene sheets were activated prior to the grafting reaction by using electron beam radiation. The changes in morphology, crystallinity and tensile parameters like deformation and stress at yield and deformation at break of PP after irradiation were investigated. The results showed that a minor crystalline reorganization takes place during the irradiation of PP at 100 kGy.The grafting has been observed to be strongly dependent on the monomer dilution in the reaction medium. After grafting of QAS (40%) and DMA (20%) it was possible to develop highly hydrophilic surfaces (water contact angle comprised between 30 and 411). The surfaces of virgin, irradiated and grafted PP were studied using polarized optical microscopy (POM) and scanning electron microscopy (SEM). Spherical particles (i.e. polystyrene or silica beads) adhering to the modified samples were studied according to the surface parameters. Adhesion tests confirmed the strong influence of substrate type (mainly hydrophilicity and roughness) and to a lesser extent underlined the role of electrostatic interactions for the design of plastic surfaces for antimicrobial applications.

The consequences of physical post-treatments (microwave and electron-beam) on food/packaging interactions: A physicochemical and toxicological approach

“…Irradiation was performed in air at a dose of 100 kGy. In terms of crystalline structure, the impact of electron beam treatment on structural changes in the PP matrix was not really significant when compared to the virgin PP (Riquet, Delattre, Vitrac, & Guinault, 2013).…”

Engineered Bioactive Polymeric Surfaces by Radiation Induced Graft Copolymerization: Strategies and Applications

“…However, the strong hydrophobicity of PP poses challenges to bonding with other surfaces and thus, it must undergo surface treatments including RIGC with polar monomers to improve its surface properties. PP film was modified with monomers such as AA [ 178 , 179 ] and their mixture [ 180 ] using RIGC (pre-irradiation) method with EB irradiation for imparting antimicrobial properties. In another study, antimicrobial properties were imparted to PP film by pre-irradiation grafting of AA, N,N-dimethylacrylamide (DMA) and the mixtures of both AA and DMA with [2-methacryloyloxy)ethyl] trimethylammonium chloride using EB.…”

“…The surface hydrophilicity varied depending on the monomer and comonomer grafted [ 181 ]. Adhesion tests for samples obtained from RIGC of N,N-dimethylacrylamide (DMA) and [2-methacryloyloxy)ethyl] trimethylammonium chloride (PMETAC) confirmed that adhesion depends mainly on the hydrophilicity and the roughness for the designed plastic surfaces for antimicrobial applications [ 179 ].…”

Preparation of Nanocomposites of Polypropylene with Carbon Nanotubes via Masterbatches Produced by In Situ Polymerization and by Melt Extrusion

“…Polypropylene (PP) is one of the most widely used thermoplastics, with applications in several segments, such as in the automotive industry, electrical and electronics, construction, packaging etc. . In their formulation, materials based on PP usually contain inorganic reinforcing fillers in order to improve their properties …”