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A series of BBL-graft-poly (L-lactide) copolymers were synthesized via ring-opening polymerization (ROP) of L-lactide (L-LA) with a biobutanol lignin (BBL) initiator and a triazabicyclodecene (TBD) catalyst under free-solvent at 135 °C. By manipulating the mass ratio of BBL/LLA, BBL-g-PLLA copolymers with tunable number-average molecular weight (Mn) (2544-7033 g mol(-1)) were obtained. The chemical structure of PLLA chains was identifiable by FT-IR, (1)H NMR and (13)C NMR spectroscopies, in combination with UV-vis spectra to provide support for the existence of the BBL in the copolymer. This provided solid evidence for the successful synthesis of BBL-g-PLLA copolymer. The thermal properties and surface characterization of BBL-g-PLLA copolymers were different from those of linear PLLA. Furthermore, the BBL-g-PLLA copolymer film showed good absorption capacity in the UV region and high transparency in the visible light region, which was expected to find significant applications in UV-protective coating film., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this paper, a "graft from" Ring-Opening Polymerization (ROP) technique was used to synthesize a lignin-graft-poly (ɛ-caprolactone) copolymer (BBL-g-PCL) using biobutanol lignin (BBL) as raw material recovered from lignocellulosic butanol residue. Polymerizations were carried out with various mass ratios of BBL and CL monomer ([BBL]/([BBL]+[CL])=1.0%, 5.0%, 10%, 20% and 40% (w/w)) to obtain BBL-g-PCL copolymers with different molecular weights, ranging from 367 to 8163gmol(-1). The grafting efficiency was preliminary evidenced by the long-term stability of dissolution of BBL-g-PCL in toluene. FT-IR and NMR analysis provided the further evidences for successful formation of BBL-g-PCL copolymer. The thermal properties of BBL-g-PCL copolymers were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). These results indicated that BBL-g-PCL copolymer had relatively good thermal stability. The static contact angle of BBL-g-PCL coating film reached to 80°. The surface functional groups and chemical composition of BBL-g-PCL copolymer was investigated in detail by X-ray photoelectron spectroscopy (XPS). The surface morphology of BBL-g-PCL copolymer was studied by Atomic force microscopy (AFM). Additionally, BBL-g-PCL coating film exhibited high absorption in the ultraviolet (UV) range, which could allow for applications in UV-blocking coatings, as well as the extents for the utilization of lignocellulosic butanol residue., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In order to develop the potential application of industrial alkali lignin, its acrylonitrile-butadiene-styrene (ABS) composites were fabricated via melt blending in the absence/presence of a compatibilizer. The lignin can uniformly disperse in the ABS matrix with number-average dispersed-phase domains of sub-micron scale, ranging from 150–250 nm, as observed by scanning electron microscopy. Infrared spectroscopy reveals that strong intermolecular interactions, mainly hydrogen bonding, were responsible for their good interfacial compatibility. Rheological behaviors show that the presence of lignin restricts to some extent the relaxation of polymer chains without affecting the processing properties of ABS resin. The presence of lignin increases storage modulus and glass transition temperature (T g) of ABS. Incorporating small amounts of lignin, e.g. 5 wt%, can produce ABS composites with enhanced tensile strength and modulus, while higher loading of lignin will reduce mechanical properties. The latter, however, can be improved by reactive compatibilization. [ABSTRACT FROM AUTHOR]

Lignin, as a natural polymer material, has the advantages of green safety, renewable, and pollution-free. It has a wide application prospect in the field of thermosetting. However, it has been attractive but a huge challenge to design high performance and high added-value lignin-based epoxy resin. Herein, lignin-based epoxy (LEP) was synthesized from moso bamboo-derived lignin, and then lignin-based epoxy/titanium dioxide (LEP/TiO 2) hybrid nanoparticle was synthesized via liquid deposition method for modifying lignin-based epoxy resin to prepare multifunctional bio-based epoxy. The results show that the LEP/TiO 2 hybrid nanoparticle exhibits a stable topological surface shape and good dispersion and uniformity. By adding 10 wt% LEP/TiO 2 hybrid nanoparticles, the multifunctional bio-based epoxy exhibits good mechanical strength and toughness, and the tensile strength and fracture toughness reach 36 MPa and 1.26 MPa·m1/2, respectively. In addition, the thermal stability, UV absorption and antibacterial properties of the multifunctional bio-based epoxy are further improved. This study provides a facile and efficient method for the preparation of high-performance multifunctional bio-based epoxy composite and a novel solution for the utilization of lignin. A novel multifunctional bio-based epoxy with improved mechanical performance, UV adsorption and antibacterial properties has been successfully prepared. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Effects of alkali lignin incorporation and in situ reactive compatibilization on the thermal stability and flame retardancy of ABS were investigated. Morphology observations show that lignin can form submicron dispersed phases in ABS matrix regardless of compatibilization. Thermal analyses show that lignin will cause a slight thermal instability of ABS due to its relatively lower thermal stability, and compatibilization reaction has little effluence on that. However, lignin can slow the degradation process and increase the char residue of ABS with increasing lignin loading, and the compatibilization does not markedly affect them. Cone calorimeter tests demonstrate that lignin can significantly reduce the heat release rate, and slow the combustion process of ABS, e.g., 20wt% lignin causing a 32% reduction in peak heat release rate (PHRR). The compatibilization can further reduce the flammability of ABS due to the improved char layer. The char residue analyses indicate that the formation of protective char layer of lignin is primarily responsible for the enhanced flame retardancy. [Copyright &y& Elsevier]