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In this study, demethylated-acylated enzymatic hydrolysis lignin (DAEHL) with excellent solubility in castor oil and antioxidant activities were prepared via the tandem modification strategy. First, iodocyclohexane simultaneously achieved β-O-4 breakage and hydrogenation, which enhanced the antioxidant activity of lignin. Furthermore, the acylation reaction by palmitoyl chloride increased the alkyl content in the lignin, which can improve the solubility of lignin in castor oil. The structural evolution of lignin showed the change in the hydroxyl group content, which induced a change in the solubility and antioxidant activity of the lignin. 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt (ABTS) radical scavenging, Fe 3+ reduction capacity and oxidation induction time demonstrated the excellent antioxidant activity of the modified lignin DAEHL. In addition, the balance between antioxidant activity and solubility of lignin was realized by the tandem modification strategy. DAEHL shows good solubility over 1 wt% in castor oil. The OIT value of the castor oil was significantly increased from 162 s (pure castor oil) to 218 s with 0.3 wt% DAEHL. In addition, the wear volume of DAEHL-castor oil is only 61 % of that of castor oil. This study allows for the high-value utilization of technical lignin as a sustainable lubricant addition in castor oil. SYNOPSIS: A tandem modification strategy for technical lignin dissolving in castor oil with antioxidant activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

The study examined the use of cellulose nanocrystals (CNCs) in poly(ethylene terephthalate) (PET)/castor oil (CO) electrospun membranes, focusing on how CNCs influenced membrane properties for aerosol filtration applications. PET membranes were fabricated using 5 wt% and 10 wt% of CNCs and 2.5 wt% CO to assess its effectiveness as a compatibilizing agent, under a solution flow rate of 25.5 μL/min, a voltage of 25 kV, and a needle-collector distance of 8 cm. Nonaligned fiber membranes featured a network of ultrafine and nanofibers, while aligned fibers had an average diameter of over 300 nm (ultrafine fibers). The PET membranes permeability parameters were applied to Forchheimer's equation. All membranes presented values of Darcian (k 1 )/non-Darcian (k 2 ) permeability coefficients in the order of 10 -13  m 2 /10 -8 m, respectively, near the range reported for commercial high-efficiency particulate air filters. CNCs acted as reinforcing agents, while CO was a compatibilizing agent, improving the material's mechanical behavior. Nonaligned PET/CO/10 wt% CNC presented a storage modulus (E') 2-fold higher/tensile strength 3-fold higher than pristine PET. Aligned PET/CO/5 wt% CNC, characterized in the preferential direction of fiber alignment, had approximately an E' 42-fold higher/tensile strength 6-fold higher than the same membrane, but tested in the perpendicular alignment direction. The glass transition temperature (T g ) values of PET (90-110 °C) did not exhibit any significant impact from membrane composition or fiber alignment. This study demonstrated the promising capability of PET-CNC bio-based electrospun membranes to be used in aerosol filtration or gas-solid and liquid-solid separations., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Rachel Passos de Oliveira Santos reports financial support was provided by The São Paulo Research Foundation (FAPESP). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The advancement of bio-based materials derived from renewable resources provides a pivotal strategic approach to address the problems of environmental pollution and scarce fossil resources. In this study, a series of bio-based waterborne polyurethanes (WPUs) with enhanced UV resistance, photothermal effect and corrosion resistance were prepared by using sorbitan monooleate (SP) and castor oil (CO) as vegetable polyols together with the introduction of sodium lignosulfonate modified of diethanolamine (DML). The WPU coatings of only 100 μm thickness, exhibited UV blocking rate > 99 % between 200 and 320 nm. Furthermore, the synthesized WPUs had superior adhesion to aluminum, tinplate, and PVC surface, with adhesion to tinplate of up to 5B and hardness of up to 3H. Additionally, the WPU coatings showed favorable photothermal effect when exposed to 1.05 W/cm 2 of near-infrared light irradiation, with maximum surface temperature of 93 °C. The WPU coatings demonstrated noteworthy corrosion protection, with high corrosion protection efficiency of 96.97 % on tinplate. This study presents a new strategy for the synthesis of bio-based WPUs with excellent ultraviolet resistance, favorable photothermal effect, corrosion protection, and degradability. The unique properties lay the foundation for the applications of bio-based WPUs in the field of industrial coatings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This work explores the electrospinnability of low-sulfonate Kraft lignin (LSL)/polyvinylpyrrolidone (PVP) solutions in N,N-dimethylformamide (DMF) and the ability of the different micro- and nano-architectures generated to structure castor oil. LSL/PVP solutions were prepared at different concentrations (8-15 wt%) and LSL:PVP ratios (90:10-0:100) and physico-chemically and rheologically characterized. The morphology of electrospun nanostructures mainly depends on the rheological properties of the solution. Electrosprayed nanoparticles or micro-sized particles connected by thin filaments were obtained from solutions with low LSL/PVP concentrations and/or high LSL:PVP ratios, whereas beaded or bead-free nanofibers were produced by increasing concentration and/or decreasing LSL:PVP ratio, due to enhanced extensional viscoelastic properties and non-Newtonian characteristics. Electrospun LSL/PVP nanofibers are able to form oleogels by simply dispersing them into castor oil at concentrations between 10 and 30 wt%. The rheological properties of the oleogels may be tailored by modifying the LSL:PVP ratio and nanofibers content. The potential application of these oleogels as bio-based lubricants was also explored in a tribological cell. Satisfactory friction and wear results are achieved when using oleogels structured by nanofibers mats with enhanced gel-like properties as lubricants. Overall, electrospinning of lignin/PVP solutions can be proposed as a simple and effective method to produce nanofibers for oil structuring., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Cellulose nanocrystals (CNCs), castor oil (CO), and recycled poly(ethylene terephthalate) (rPET), were used to add value to renewable raw materials and to a recycled polymer produced worldwide, producing mats composed of fibers on the nano- and submicrometric (ultrathin) scales through a sustainable process. Bio-based electrospun mats composed of aligned (rotary collector) and nonaligned (static collector) nanofibers/ultrathin fibers were produced from the electrospinning of solutions prepared from rPET (mixed with CO, CNCs, or CNCs/CO). The contact angle results showed that the CNC mat surfaces composed of nonaligned fibers were hydrophilic, and in contrast, these surfaces were hydrophobic when composed of aligned fibers. Among the mats composed of nonaligned fibers, PET/CO/CNC exhibited storage and Young's moduli approximately eleven and ten times, respectively, better than those of neat rPET. The PET/CO/CNC mat showed both modulus and tensile strength values higher than those of PET/CNC, when characterized in the preferential direction of fiber alignment. Electrospun mats were obtained from environmentally sound raw materials with diversified properties, which were modulated by the type of collector used, as well as whether CO and CNC were mixed with rPET, and have the potential for use in applications such as membrane separation processes and biomedical applications., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Kraft lignin (KL) and castor oil (CO) were used as polyols in the synthesis of bio-based polyurethanes (PUs) in the absence of both solvents and catalysts at room temperature with simultaneous film formation. KL was purified (PKL), and both KL and PKL were fully characterized. CO was mixed with different percentages of PKL (0%, 10%, 30%, and 50%), as well as with polymeric methyl phenyl diisocyanate. After degassing, the reaction mixture was stirred; when the medium viscosity was suitable for spreading, it was poured onto a glass plate, and the thickness was adjusted using an extender. The storage modulus (E', 25 °C) and tensile strength of the lignopolyurethane films (LignoPU COPKL ) were higher than those of the control film (PU CO ). LignoPU COPKL30 and LignoPU COPKL50 did not break under the conditions that the other films broke under. It was noted phase segregation (rigid and flexible domains) for LignoPU COPKL30 and LignoPU COPKL50 , and the glass transition temperature (T g ) of the flexible domains (96.2 °C and 52.3 °C, respectively) was higher than that of PU CO (8.4 °C). The formed films were also characterized by scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, contact angles, and swelling tests. To our knowledge, the approach of this study is unprecedented., (Copyright © 2018. Published by Elsevier B.V.)

A novel bio-based polyurethane/chitosan foam (PU/chitosan) was synthesized using a polyol derived from castor oil and applied to remove Food Red 17 dye (FR17) from aqueous solutions. PU/chitosan foam presented better characteristics and adsorption potential than polyurethane foam (PU). PU/chitosan foam showed a semi-crystalline structure, with several functional groups, high porosity and good mechanical properties. These characteristics are adequate for adsorptive separations. Using identical adsorption conditions, PU/chitosan was able to remove >98% of FR17 dye from the solution, while, PU removed only 40%. The adsorption of FR17 on PU/chitosan composite foam was favored at pH 2. Pseudo-second order model was the most adequate to represent the kinetic data. The equilibrium data followed the Sips model, with a maximum adsorption capacity of 267.24 mg g -1 . The adsorption process was spontaneous, favorable and endothermic. The results showed that polyurethane foams are capable to support chitosan, generating an adsorbent with better mechanical characteristics and high potential to remove anionic dyes from aqueous media., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Olanzapine is an atypical antipsychotic, undergoes extensive first pass metabolism, also has poor aqueous solubility and belongs to BCS (Biopharmaceutical Classification System) Class II drug) exhibit low oral bioavailability. To overcome this and to enhance the bioavailability, intestinal lymphatic transport of drugs can be exploited through Nano structured lipid carriers (NLCs). The NLCs were formulated by solvent diffusion method using solid lipid (glyceryl tripalmitate), liquid lipid (castor oil) and surfactants (Pluronic F-68, Soylecithin). The formulated NLCs were characterized for physico-chemical properties, in-vitro release studies and in-vivo oral bioavailability. F6 has shown average particle size of 158.5 nm with PI of 0.115 indicating narrow particle size distribution and follows uni modal distribution. It was found that the batch with stearyl amine has a zeta potential of 28.39 mV which confers stability to the dispersion. Bioavailability studies indicate that there was more than 5½-fold increase in oral bioavailability in case of NLCs (F6) compared to olanzapine suspension which indicates that NLCs provided sustained release of the drugs, and these systems can be the preferred as drug carriers for lipophilic drugs in long term disease conditions such as schizophrenia for enhanced bioavailability., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Surgical adhesives have been used for several applications, including haemostasis, sealing air leakages and tissue adhesion. The aim of this work was to develop a biodegradable urethane-based bioadhesive containing free isocyanate groups. This material presents the advantage of being biodegradable, biocompatible and having the capacity of reacting with amino groups present in the biological molecules. A urethane based on castor oil (CO) was synthesized by reaction of the molecule with isophorone diisocyanate (IPD). The characterization of the material was accomplished by different techniques: ATR-FT-IR (attenuated transmittance reflection-Fourier transform infrared), swelling capacity determination, evaluation of the moisture curing kinetics, reaction with aminated substrates and determination of surface energy by contact angle measurement. The study of the urethane thermal properties was performed by DMTA (dynamical mechanical thermal analysis) and TGA (thermogravimetric analysis). The haemocompatibility of the urethane was also evaluated by thrombosis and haemolysis tests.