Interaction and Release of Catechin from Anhydride Maleic-Grafted Polypropylene Films

Abstract

In this paper, investigations were carried out on catechin-loaded maleic anhydride (MAH)-modified polypropylenes (PP). Two maleic-modified polypropylenes (PPMAH) with different maleic concentrations have been blended with PP and catechin to obtain composites of improved catechin retention with the aim of studying the possible interactions between these grafted polymers with antioxidants, and a secondary interest in developing an active antioxidant packaging. Composite physicochemical properties were measured by thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and oxidation induction time (OIT)) and infrared spectroscopy studies. Catechin release profiles into food simulants were obtained by HPLC-PDA-QqQ, following European legislation. Antiradical activity of composites was analyzed by the ABTS and DPPH method. The formation of intermolecular hydrogen bonds between catechin and functionalized PP has been confirmed by Fourier transform infrared (FTIR) studies. Besides, a small fraction of ester bonds, formed as a result of a chemical reaction between a fraction of the hydrolyzed anhydride and the catechin hydroxyl groups, is not discarded. OIT results also showed an increase in antioxidant effectiveness caused by the presence of catechin- and maleic-modified PPMAH in the blend formulations. Incorporation of MAH-grafted PP increased substantially the retention rate of catechin, being dependent on the MAH content of the grafted polypropylene. The described interactions between catechin and maleic groups, together with changes in PP morphology in comparison with reference PP explained lower antioxidant release. Besides formulation, antioxidant release was dependent on the type of food, the temperature, and the time.

Enhancing the Thermal Stability of Polypropylene by Blending with Low Amounts of Natural Antioxidants

“…This unexpected results can be related with the fact that flavonones mainly interact with polymeric matrices by hydrogen bonding interactions between hydroxyl groups and carbonyl groups of the polymeric matrices, which are not present in PP. In this sense, de Dicastillo et al blended maleic anhydride modified poly(propylene) (MAPP) with flavonoids and found the formation of intermolecular hydrogen bonds due to the maleic anhydride modification on polypropylene which allowed hydrogen bonding interactions between hydroxyl groups of catechin and carbonyl groups of MAPP . Slightly higher OIT values were found when the PP was blended with p ‐coumaric, trans‐ferrulic and chlorogenic acids, resulting in 1.1, 1.2, and 1.9 min, respectively.…”

“…In this sense, de Dicastillo et al blended maleic anhydride modified poly(propylene) (MAPP) with flavonoids and found the formation of intermolecular hydrogen bonds due to the maleic anhydride modification on polypropylene which allowed hydrogen bonding interactions between hydroxyl groups of catechin and carbonyl groups of MAPP. [38] Slightly higher OIT values were found when the PP was blended with p-coumaric, transferrulic and chlorogenic acids, resulting in 1.1, 1.2, and 1.9 min, respectively. The higher antioxidant protection provided by these antioxidants could be related with their longer aliphatic chains which allowed higher molecular mobility and thus facilitating their interaction with PP polymeric matrix.…”

Antimicrobial Carvacrol-Containing Polypropylene Films: Composition, Structure and Function

“…When comparing the IR spectra of the films to those of the neat components (PP, HNTs and carvacrol), no evident shifts in the characteristic peaks are observed, see Figure 2. As the sensitivity of the FTIR may be insufficient to characterize such interactions [58] if they exist, we have employed molecular dynamics (MD) simulations as a tool to study the interactions between the nanocomposite components.…”

A traditional aboriginal condiment as an antioxidant agent in the development of biodegradable active packaging

“…Migration studies were conducted at 40 °C in accordance with European Union regulations. Double‐sided, total immersion migration tests were performed as follows: a 3‐cm 2 piece of each film and 5 mL of simulant (area‐to‐volume ratio around 6 dm 2 /L) were placed in a glass vial, and periodically, the release of active agents were measured indirectly as the antioxidant activity of food simulants through 2,2‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) method …”