Design of Sustainable Materials by Cross-linking a Biobased Epoxide with Keratin and Lignin

Abstract

Awareness of the environmental impact of using polymeric materials obtained from petroleum is causing increased interest in sustainable materials manufacturing. Here, we present the elaboration of fully biobased materials using an aromatic epoxy resin matrix coming from wood biomass and two natural by-products, namely, keratin from chicken feathers and lignin. In situ FTIR kinetic studies show that the two natural fillers increase the conversion of the epoxide during cross-linking. This result, together with DSC studies, proves the chemical interactions between the keratin or lignin and the epoxide network. Up to 30% of these natural components could be reacted and incorporated into the epoxide with good compatibility. The thermomechanical properties of the elaborated materials are comparable to those of commercial ones.

Physico-Chemical Characterization of Keratin from Wool and Chicken Feathers Extracted Using Refined Chemical Methods

“…Improving the extraction method for keratin from wool and feather waste can be a measure inspired by circular economy to reduce the environmental impact subsequent to the disposal of this waste, while providing indications for the “good practice” of its use as a secondary raw material. Landfilling, burying, and incinerating, which are still common procedures for this waste, represent environmental threats also in view of the limited significance, if any, of keratin structures for soil nutrition, due to the limited variety of micro-organisms able to feed on them [ 7 ].…”

Recent development on bio‐based thermosetting resins

“…[34][35][36] With the help of phenolic group to the ring-opening of epoxy, as a copolymer unit or curing agent was also found to have improved performance. 37 However, what follows is poor controllability caused by the complex structure, larger molecular weight and lower average functionality. Lignin derivatives, vanillin and eugenol are S C H E M E 2 A diol-based epoxy resin synthesized from isobutyric acid the two most used platform compounds when it comes to bio-based epoxy resin, both of which have the advantages of high reactivity, simple structure and availability.…”

“…Owing to its nature with potential for epoxidation, direct grafting epoxy group into lignin or depolymerized lignin is the easiest way to obtain lignin‐based epoxy resin 34–36 . With the help of phenolic group to the ring‐opening of epoxy, as a copolymer unit or curing agent was also found to have improved performance 37 . However, what follows is poor controllability caused by the complex structure, larger molecular weight and lower average functionality.…”

Sustainable Composites from Nature to Construction: Hemp and Linseed Reinforced Biocomposites Based on Bio-Based Epoxy Resins

“…Another relevant compound used in this study is a biorefinery-derived side-product: humins, which are generated in the production of furandicarboxylic acid [ 44 , 45 , 46 , 47 ]. Humins are mainly composed of aromatic rings, containing different functionalities which vary depending on the biorefinery processing: aldehydes, hydroxyls, carboxylic and ketones.…”