Ionic liquid pretreatment at high solids loading: A clean approach for fabrication of renewable resource based particulate composites

Abstract

Recently, the concept of high solids loading in ionic liquid (IL) based pretreatment of lignocellulosic biomass has gained numerous attention due to significant economic, environmental, and sustainability benefits. The objective of the present work was to investigate the impact of ILs pretreatment of lignocellulosic oil palm frond (OPF) biomass at high solids loading on the mechanical and thermal properties of the composite panels. The process combines the pretreatment of OPF particles with ILs [bmim][Cl] (1‐butyl‐3‐methylimidazolium chloride) and [emim][OAc] (1‐ethyl‐3‐methylimidazolium acetate) followed by IL recovery by rinsing with acetone‐water mixture prior to mixing of OPF particles with polymer binder to fabricate compression‐molded composite panels. Untreated and treated OPF particles were characterized by scanning electron microscopy, X‐ray diffraction, thermogravimetric analysis, and chemical composition analysis. Further, the effect of ILs pretreatment on kinetics of thermal degradation of biocomposites was evaluated by activation energy approach. Maximal flexural strength, modulus, and strain energy density (SED) of 25 MPa, 1,928 MPa, and 0.48 MJ/m3, respectively, were found for IL [emim][OAc] treated composite. Besides, thermal properties of IL treated composites were also improved. Present study could be a significant step toward practical IL pretreatment strategies for manufacturing of lignocellulosic based composite materials. POLYM. COMPOS., 39:1994–2003, 2018. © 2016 Society of Plastics Engineers

A Review on the Partial and Complete Dissolution and Fractionation of Wood and Lignocelluloses Using Imidazolium Ionic Liquids

“…Sometimes, the composite is made of a mixture of wood and cellulose [204][205][206]. Other times, the plasticized wood is processed with another polymer such as thermoplastic starch [207].…”

Ionic liquids assisted processing of renewable resources for the fabrication of biodegradable composite materials

“…1 Structures of the ILs used for dissolution of biopolymers and lignocellulosic materials for fabrication of biocomposites: 24,93 Recently, we have explored high solids loading, because of lower overall cost, improved efficiency and environmental benefits. 51 Thus, the possibility of high-throughput pretreatment in a continuous process could improve the potential for the use of ILs as a cost-effective and extremely promising technology for manufacturing sustainable composites from various polysaccharide raw materials. The most important advantages of ILs as dissolution media for the fabrication of polysaccharides based biocomposites is the possibility of ILs recycling and product recovery schemes which are not viable with conventional organic solvent systems.…”

“…50 In addition, many biopolymers and lignocellulosic fibers after regeneration from their IL solutions exhibited high thermal and operational stability. 51,52 Therefore, ILs are receiving increased interest as new and highly effective dissolution media for a wide range of biodegradable polymers and lignocellulosic materials. The main objective of this review is to present a brief overview of the current state-of-the-art on the role of ILs as dissolution media for various polysaccharides for engineered green materials applications.…”

Glycerol Assisted Pretreatment of Lignocellulose Wheat Straw Materials as a Promising Approach for Fabrication of Sustainable Fibrous Filler for Biocomposites

“…However, the incorporation of lignocellulosic fibers into the polymer matrix phase for composite manufacturing is challenging due to non-cellulosic constituents present over the fiber’s surface which impart weak fiber-binder interfacial conglutination [ 3 ]. Conversely, high susceptibility to thermal degradation is another ambitious problem during the development of lignocellulosic fiber based composites during manufacturing and service [ 4 ].…”