Several efforts have been dedicated to the development of lignin-based polyurethanes (PU) in recent years. The low and heterogeneous reactivity lignin hydroxyl groups towards diisocyanates, arising from their highly complex chemical structure, limits application this biopolymer PU synthesis. Besides well-known differences aliphatic aromatic groups, experimental work which both types hydroxyl, especially ones present syringyl (S-unit), guaiacyl (G-unit), p-hydroxyphenyl (H-unit) building...

This work aimed to evaluate the influence of aliphatic and aromatic hydroxyl level on polyurethane adhesive property chemical structure. was obtained through reaction technical Kraft lignin (TKL) as polyol with diphenylmethane diisocyanate (MDI). Thus, lignopolyurethane adhesives were NCO:OH ratios 0.8:1.0, 0.9:1.0, 1.0:1.0, 1.1:1.0, 1.2:1.0. Initially only TKL taken into consideration in stoichiometry order define mass ratio between MDI polyol. Subsequently, using same considering total...

In 2021, global petroleum-based plastic production reached over 400 million metric tons (Mt), and the accumulation of these non-biodegradable plastics in environment is a worldwide concern. Polyhydroxybutyrate (PHB) offers many advantages traditional plastics, being biobased, completely biodegradable, non-toxic. However, its use are still challenging due to low deformation capacity narrow processing window. this work, two linear-chain polyester oligomers were used as plasticizers improve...

Thermoplastic elastomer gels based on styrenic triblock copolymers have been increasingly used as dielectric elastomers, particularly due to the possibility of tailoring their properties composition.However, these materials a low relative permittivity, primarily attributed dipole moment.Consequently, this characteristic poses challenge for application elastomers.In work, we aim assess impact adding kraft lignin thermoplastic gels.Additionally, investigate effects dispersion viscoelastic and...

Low surface energy and poor adhesion are well-known characteristics of polypropylene (PP). Surface treatments such as plasma, corona, laser usually applied to overcome these limitations. However, current studies highlight the incorporation hydrophilic or amphiphilic polymers into hydrophobic low-surface-energy an alternative for increasing thus improving adhesion. Lignin could be a promising polymer use in energy. In this work, PP/kraft lignin composites were obtained by incorporating up 5...

Additive manufacturing, particularly Stereolithography (SLA), has gained widespread attention thanks to its ability produce intricate parts with high precision and customization capacity. Nevertheless, the inherent low mechanical properties of SLA-printed limit their use in high-value applications. One approach enhance these involves incorporation nanomaterials, graphene oxide (GO) being a widely studied option. However, characterization GO nanocomposites under various stress loadings...

Lignin, a renewable and widely available biopolymer, has been explored as an additive in polyolefins to develop high value-added materials. However, its low compatibility with polymers like polypropylene (PP) often causes poor particle dispersion compromised mechanical properties. Esterification proven effective enhancing lignin-polyolefin interactions. This study evaluated the incorporation of kraft lignin (KL) maleic anhydride-modified (MAKL) into PP, focusing on blends’ thermal,...

Elastomers based on block copolymers can self-organize into ordered nanoscale structures, making them attractive for use as flexible conductive nanocomposites. Understanding how structures impact electrical properties is essential practical applications. This study investigated the morphological evolution of elastomers polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) with aligned single- or multi-wall carbon nanotubes (SWCNTs MWCNTs) and their conductivity under large...

Pyrolytic lignin (PL) has emerged as a promising renewable material for the production of polyurethanes (PU) due to high concentration hydroxyl groups in its structure, being potential substitute petroleum-based polyols. On one hand, functionality and liquid form PL favor application polyol PU formulations. other inherent heterogeneity still imposes challenge development new materials with reproducible properties. In this work, aiming overcome these limitations, an acetone-water...

Bioplastics hold significant promise in replacing conventional plastic materials, linked to various serious issues such as fossil resource consumption, microplastic formation, non-degradability, and limited end-of-life options. Among bioplastics, polyhydroxyalkanoates (PHA) emerge an intriguing class, with poly(3-hydroxybutyrate) (P3HB) being the most utilized. The extensive application of P3HB encounters a challenge due its high production costs, prompting investigation sustainable...

Thermoplastic elastomer gels have been highlighted in recent years due to their highly tunable properties, becoming interesting electroactive polymers for the fabrication of dielectric actuators. These materials are obtained by adding high concentrations an organic solvent, such as mineral oil, a block copolymer thermoplastic elastomer. The solvent is selective one blocks and, therefore, significantly improves flexibility. However, tend reduce mechanical stability these materials,...

Lignin, one of Earth’s most abundant biopolymers, is rich in phenolic and aliphatic functional groups, offering significant potential for chemical modification. Technical lignin, a byproduct the kraft process, produced large quantities annually can be used to enhance properties polymer matrices such as polypropylene (PP). PP, widely nonpolar polymer, suffers from low surface free energy, leading poor adhesion properties. Combining PP with polar, renewable-source polymers like lignin improve...

Dielectric elastomers are materials of increasing interest in applications as electroactive polymers. In this field, with high dielectric constant and low elastic modulus essential for actuation performance, block copolymer gels among the best candidates these applications. study SEBS containing mineral oil were obtained order to evaluate their morphological structure rheological properties, well impact properties on mechanical behavior. The variation was verified a function viscosity gel...

In this study, the mechanical strength and AC short term breakdown of polystyrene‐ b ‐poly(ethylene‐ co ‐butylene)‐ ‐polystyrene (SEBS) thermoplastic elastomer clay‐containing nanocomposites have been investigated as function their morphologies. The SEBS/clay with tailored morphologies were prepared previously by different processing techniques. They featured orientations clay platelets well polystyrene (PS) block nanodomains, namely: isotropic, oriented, partially oriented unfilled SEBS...

Abstract Fused Filament Fabrication is an Additive Manufacturing technology that allows continuous fiber reinforcement to be incorporated into printed parts during manufacturing. Materials like short carbon reinforced Polyamide 6 serve as matrix material between the fibers, resulting in a superposition of and reinforcement. This facilitates production lightweight components with high rigidity strength. Furthermore, enables integration complex geometries Triply Periodic Minimal Surface...

Abstract Numerous efforts focus on renewable epoxy resin development, with lignin emerging as a viable green alternative to fossil‐derived resources. Being Earth's second‐most abundant organic molecule, lignin, rich in phenolic groups, shows promise substitute for bisphenol A diglycidyl ether of (DGEBA) production. This work successfully modifies Kraft (KL) via one‐step epoxidation (KLE) and phenolation prior (KLPE), significantly increasing oxirane ring content. Characterization FTIR 1 H...

Purpose: of this paper was to develop and characterize the mechanical behaviour a structural composite obtained from bio-based polyurethane matrix reinforced with fiberglass. Design/methodology/approach: Castor oil Kraft lignin-containing polyol applied for synthesis. Structural by reinforcing renewable source polymer fiberglass mat. Polyester resin also comparison, following same process reinforcement conditions. Mechanical characterization carried out through uniaxial tensile, flexural...