Development and characterization of multilayer films based on polyhydroxyalkanoates and hydrocolloids

Abstract

New biodegradable polymeric materials have been developed in order to minimize the environmental impact caused by the traditional packaging found in the market. Polyhydroxyalkanoates (PHAs) are biopolymers with important features such as biodegradability and biocompatibility; however, the costs associated with PHAs production and the limited mechanical properties reduce their application. Whey is a residual product from dairy industry and gelatin is a biopolymer with good processing characteristics. In this context, a filmogenic solution based on these two biopolymers was incorporated into pure PHA films to improve their optical, mechanical, and structural properties. The filmogenic solution was prepared from gelatin, cheese whey and PHAs, using glycerol as plasticizer agent. The multilayers films (gelatin concentrations at 3 and 5%, w/v) showed higher values for all properties when compared with the PHA standard film. In this sense, the addition of this solution was responsible for the improvement of the film properties. The 5% gelatin multilayers films added of cheese whey and PHAs showed better results when compared with the multilayers films with gelatin at 3%. The film composed of gelatin 5% and cheese whey showed a water vapor permeability ranging from 0.45 g mm/m 2 /d/kPa, elongation of 2.18%, and opacity of 14.5%. However, the results of the morphological analysis showed that both films presented a homogeneous surface without cracks. Moreover, the results of the thermal analysis of both films indicate polymeric miscibility. Thus, the choice of the best film will depend on its applicability.

Novel Production Methods of Polyhydroxyalkanoates and Their Innovative Uses in Biomedicine and Industry

“…A blend of PHB/poly(butylene adipate-co-terephthalate; PBAT), together with the antimicrobial compounds of 1-allylhydantoin (AH) and perfluorooctyl acrylate (PFA), gave, as a result, a PHA-based membrane with ductility, stability, and hydrophobicity adequate for packaging applications [ 91 ]. Other mixtures, such as PLA/PHB [ 92 ], polyhydroxyalkanoates/cheese whey/gelatin (PHAs/CW/Gelatin) [ 93 ] and PHAs/nanokeratin [ 94 ] and PLA-based thermoplastic polyurethane (PLAPU) [ 95 ] also possess great features to be used as packaging material [ 86 ].…”

Nile tilapia (Oreochromis niloticus) waste protein-based films

“…The films were produced by the casting technique as previously reported [1]. A first filmogenic solution was obtained from Nile tilapia protein isolate, which was dispersed in 50 mL of distilled water and then maintained at 30°C under constant magnetic stirring (350 rpm) (Tecnal, model TE -0851, São Paulo, Brazil) for 10 min to rehydration.…”

“…The demand for new materials and technologies capable of minimizing damage to the environment has increased significantly in the past years. Research around the world has been growing with the interest in reducing and replacing the use of materials that are difficult to degrade [1,2]. Biodegradable films obtained from natural polymers, e.g.…”