HDPE/Chitosan Blends Modified with Organobentonite Synthesized with Quaternary Ammonium Salt Impregnated Chitosan

Influence of Quaternary Ammonium Salt Functionalized Chitosan Additive as Sustainable Filler for High-Density Polyethylene Composites

In this study, an antimicrobial packaging material was successfully developed with blends of high-density polyethylene (HDPE) and chitosan (CS) made by melt processing. In the different HDPE/CS composites, the CS content effect (up to 40%), and the addition of quaternary ammonium salt functionalized chitosan (CS-CTAB) as an additive were evaluated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile strength, scanning electron microscopy (SEM) and antimicrobial activity. When analyzing the effect of the additive in the different HDPE/CS composites, it was observed that the compositions with 10 and 20 %wt of chitosan showed better elongation values (~13% and 10%) as well as a higher decomposition temperature at 20% mass loss (T20) varying from (321-332 °C and 302-312 °C), respectively, in relation to the other compositions, regardless of the type of additive used, it acted as an antimicrobial agent, promoting inhibition of microbial growth against the strains gram-positive and gram-negative used in this work, making the different HDPE/CS composites suitable candidates for use in food packaging.

Biodegradable Antimicrobial Food Packaging: Trends and Perspectives

This review presents a perspective on the research trends and solutions from recent years in the domain of antimicrobial packaging materials. The antibacterial, antifungal, and antioxidant activities can be induced by the main polymer used for packaging or by addition of various components from natural agents (bacteriocins, essential oils, natural extracts, etc.) to synthetic agents, both organic and inorganic (Ag, ZnO, TiO2 nanoparticles, synthetic antibiotics etc.). The general trend for the packaging evolution is from the inert and polluting plastic waste to the antimicrobial active, biodegradable or edible, biopolymer film packaging. Like in many domains this transition is an evolution rather than a revolution, and changes are coming in small steps. Changing the public perception and industry focus on the antimicrobial packaging solutions will enhance the shelf life and provide healthier food, thus diminishing the waste of agricultural resources, but will also reduce the plastic pollution generated by humankind as most new polymers used for packaging are from renewable sources and are biodegradable. Polysaccharides (like chitosan, cellulose and derivatives, starch etc.), lipids and proteins (from vegetal or animal origin), and some other specific biopolymers (like polylactic acid or polyvinyl alcohol) have been used as single component or in blends to obtain antimicrobial packaging materials. Where the package's antimicrobial and antioxidant activities need a larger spectrum or a boost, certain active substances are embedded, encapsulated, coated, grafted into or onto the polymeric film. This review tries to cover the latest updates on the antimicrobial packaging, edible or not, using as support traditional and new polymers, with emphasis on natural compounds.