Recent Advances in Antioxidant Polymers: From Sustainable and Natural Monomers to Synthesis and Applications

Abstract

Advances in technology have led to the production of sustainable antioxidants and natural monomers for food packaging and targeted drug delivery applications. Of particular importance is the synthesis of lignin polymers, and graft polymers, dopamine, and polydopamine, inulin, quercetin, limonene, and vitamins, due to their free radical scavenging ability, chemical potency, ideal functional groups for polymerization, abundance in the natural environment, ease of production, and activation of biological mechanisms such as the inhibition of the cellular activation of various signaling pathways, including NF-κB and MAPK. The radical oxygen species are responsible for oxidative damage and increased susceptibility to cancer, cardiovascular, degenerative musculoskeletal, and neurodegenerative conditions and diabetes; such biological mechanisms are inhibited by both synthetic and naturally occurring antioxidants. The orientation of macromolecules in the presence of the plasticizing agent increases the suitability of quercetin in food packaging, while the commercial viability of terpenes in the replacement of existing non-renewable polymers is reinforced by the recyclability of the precursors (thyme, cannabis, and lemon, orange, mandarin) and marginal ecological effect and antioxidant properties. Emerging antioxidant nanoparticle polymers have a broad range of applications in tumor-targeted drug delivery, food fortification, biodegradation of synthetic polymers, and antimicrobial treatment and corrosion inhibition. The aim of the review is to present state-of-the-art polymers with intrinsic antioxidant properties, including synthesis scavenging activity, potential applications, and future directions. This review is distinct from other works given that it integrates different advances in antioxidant polymer synthesis and applications such as inulin, quercetin polymers, their conjugates, antioxidant-graft-polysaccharides, and polymerization vitamins and essential oils. One of the most comprehensive reviews of antioxidant polymers was published by Cirillo and Iemma in 2012. Since then, significant progress has been made in improving the synthesis, techniques, properties, and applications. The review builds upon existing research by presenting new findings that were excluded from previous reviews.

On the Use of Oxidation Induction Time as a Kinetic Parameter for Condition Monitoring and Lifetime Evaluation under Ionizing Radiation Environments

“…In order to suppress the environmental degradation of the mentioned polymers and to extend their service life, stabilizing additives are used [44,45]. Antioxidants are largely used with many polymers because of their capacities to either annihilate free radicals (radical scavenger-type antioxidants) or decompose hydroperoxides in a way that is not harmful to the polymer.…”

“…(c) The OIT values, which are determined at high temperatures specific to the test, correspond to the lifetime of the material under the conditions of exposure. The OIT value is directly proportional to the concentration of antioxidants in the polymeric material [2,35,45]. Therefore, OIT measurement can be used to "titrate" the antioxidant content of the sample.…”

Antioxidant Polymers via the Ugi Reaction for In Vivo Protection of UV-Induced Oxidative Stress

“…Incorporating small antioxidant molecules into polymeric structures via copolymerization with water-soluble monomers can efficiently improve their water solubility, stability, safety, and metabolism time . However, the antioxidative groups in these small molecules are often modified to obtain polymers with dramatically decreased antioxidant activity . Recently, some methods have been developed such that the excellent antioxidant activity of monomers dose not lose after inclusion into polymers. − However, the facile methods to simultaneously introduce multiple antioxidant groups into polymers are not common, which limit the further development and research of antioxidative polymers.…”

Polymeric Antioxidant via ROMP of Bioderived Tricyclic Oxanorbornene Based on Vanillin and Furfurylamine

“…Consequently, polymeric antioxidants have gained much interest to overcome these drawbacks by limiting the mobility of antioxidant molecules due to their high molar masses. , Polymeric antioxidants could be synthesized via two main strategies: (I) conjugation of sterically hindered phenol moieties to a pre-synthesized or natural polymer and (II) polymerization of antioxidant monomers. ,− In this context, several studies have reported the radical polymerization of vinyl monomers bearing hindered phenol moieties. , However, the generated radicals during the polymerization process could be inhibited by means of the pendant antioxidant moieties. Hence, ring opening metathesis polymerization (ROMP) arises as an impressive technique for the development of well-defined polymers with antioxidant moieties due to the tolerance of Grubbs catalysts (Ru-based) toward many functional groups. − Driven by strain release, (oxa)­norbornenes as typical ROMP monomers have been conjugated with different hindered phenol moieties and successfully polymerized by ROMP. − …”