some innovative solutions are proposed to the problem of the unavoidable physical migration of antioxidants from plastic films for packaging, in order to minimize the consequent undesirable effect of food contamination. in previous exploratory tests, phenolic antioxidant co-units were achieved and incorporated into polyethylene chain and now the work is extended to create new families of polyme...

Reverse gyrase introduces positive supercoils to circular DNA and is implicated in genome stability maintenance in thermophiles. The extremely thermophilic crenarchaeon Sulfolobus encodes two reverse gyrase proteins, TopR1 (topoisomerase reverse gyrase 1) and TopR2, whose functions in thermophilic life remain to be demonstrated. Here, we investigated the roles of TopR1 in genome stability maint...

a fourth-generation ziegler-natta catalyst was prepared to synthesize polypropylene (pp), which was stabilized by in situ polymerization employing lignin as antioxidant. the antioxidant properties of lignin were compared with those of the commercial antioxidant irganox 1010. the presence of lignin in the reaction medium slightly decreased the catalytic activity of the reaction. the isotacticity...

the main objective of the present work was to synthesis polyamide 6 through anionic polymerization of ε-caprolactam in an internal mixer. the reaction time and the rheological properties of samples during the polymerization were studied. the samples were characterized by thermo gravimetry analysis (tga), differential scanning calorimeter (dsc) and ft-ir spectrometer. the melt flow behavior and ...

This work involves the degradation of plastic waste in the presence of three different nanocatalysts. A thin film of LLDPE was formed with all three nanocatalysts separately in the solvent. Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetric (DSC) analysis of polymers suggest that the presence of these catalysts lowers the degradation temperature and the change mechanism of...

Kinetic equations are analyzed for thermal degradation of polymers. The governing relations are based on the fragmentation–annihilation concept. Explicit solutions to these equations are derived in two particular cases of interest. For arbitrary values of adjustable parameters, the evolution of the number-average and mass-average molecular weights of polymers is analyzed numerically. Good agree...

This review summarizes the state-of-the-art knowledge of the usage of poly(hydroxy alkanoate)s in medical and sanitary applications. Depending on the monomers incorporated into the polymers and copolymers, this class of polymers exhibits a broad range of (thermo-)plastic properties, enabling their processing by, e.g., solution casting or melt extrusion. In this review, strategies for the polyme...