Maleic Anhydride Research Articles (Page 1)

This study addresses developing systematic guidelines for the design of concentration control in the oxidation of benzene to maleic anhydride within a tubular reactor. The influence of step size selection and temperature sensor location on the tuning and performance of a PI/P cascade control system applied to the oxidation process was evaluated. The reactor’s dynamic behavior was analyzed using numerical simulations based on the solution of the Fortran mathematical model. Sensor positions and multiple step sizes (from +10% to −10%) were analyzed to characterize reactor dynamics and optimize control parameters. The results show that a controller design corresponding to a −9% step in the jacket temperature offered the best performance, ensuring process stability and selectivity. In contrast, step changes between +10% and −8% caused temperature deviations beyond safe limits. Since maleic anhydride is an essential precursor in the production of resins, plastics, lubricants, and pharmaceutical intermediates, optimizing the efficiency and safety of its production represents a significant benefit to the global chemical industry.

Low-temperature curing, flame-retardant and water-resistant modified cellulose-chitosan adhesive based on organic-inorganic hybridization.

Incorporating cyclodextrins (CDs) into ionically crosslinked polysaccharide matrices offers a promising strategy for developing well-defined, safe-by-design and biocompatible carrier systems with tunable rheological properties. In this study, β-cyclodextrin (β-CD) was functionalized with citric acid (CDC) and maleic anhydride (CDM) using solvent-free synthesis to improve compatibility with alginate hydrogels. The modified CDs were characterized by FTIR, 1H NMR, DLS, zeta potential, and MS, confirming successful esterification (4.0 and 3.4 –OH substitution for CDC and CDM, respectively) and stable aqueous dispersion. Rheological measurements showed that native CD accelerated gelation (within approximately 30 s), while CDC and CDM delayed crosslinking (by 2 to 13 min) and reduced gel strength, narrowing the linear viscoelastic range to 0.015–0.089% strain due to competition between polycarboxylated CDs and alginate chains for Ca2+ ions. Vibrational prilling produced alginate microbeads with diameters of 800–1000 µm and a simultaneous increase in size and CD concentration. Hydrogels demonstrated high CD retention (>80% after 28 h) and slightly greater release of CDC and CDM than native CD. Overall, solvent-free modification of CDs with citric and maleic acids provides a sustainable approach to tailoring the gelation kinetics, viscoelasticity, and release behavior of alginate-based hydrogels, offering a versatile, food- and health-compliant platform for controlled delivery of bioactive compounds.

The reinforcing effect of styrene monomer on the maleic anhydride grafting degree and enhancing the adhesion strength of multi-layered films

Highly selective hydrogenation of maleic anhydride to succinic anhydride over confined nickel catalyst anchored on MOR zeolite

ABSTRACT Despite numerous studies on polycarbonate (PC)/acrylonitrile‐butadiene‐styrene (ABS) blends, the full impact of ABS‐grafted maleic anhydride (ABS‐g‐MA) as a compatibilizer over a broad range of blend ratios has not been thoroughly investigated. This research provides a comprehensive assessment of how ABS‐g‐MA influences the rheological, mechanical, thermal, and morphological properties of PC/ABS blends with varying compositions. Melt flow index (MFI) measurements indicate a decrease as PC content increases, due to its inherently higher viscosity, with a further reduction following ABS‐g‐MA addition, suggesting enhanced interfacial interactions and molecular entanglement. Rheological data reveal notable increases in solid‐like behavior and viscosity with higher compatibilizer content, indicating improved phase connectivity. These rheological enhancements correspond to a significant rise in impact strength, particularly at a 1:1 PC/ABS weight ratio, attributed to stronger interfacial adhesion and more efficient stress transfer. Scanning electron microscopy (SEM) images confirm finer phase dispersion and reinforced interfaces in the compatibilized blends. By integrating these multi‐scale observations, this study reveals the compatibilization mechanism of ABS‐g‐MA, providing valuable guidance for optimizing PC/ABS blend performance in advanced applications.

The effects of particle size and species type were evaluated relative to the resistance to screwing and nailing of wood-plastic composites (WPC) made from the sawdust of pine, beech, poplar, and mixtures of these species (40%, 20%, and 40%, respectively), as well as alder species with a high-density polyethylene matrix. Wood-plastic composites were made from dried sawdust of the above species, after sizing to a weight ratio of 70% as filler with high-density polyethylene (HDP) by discontinuous pressing at a temperature of 185 °C, in two particle sizes of 40- and 80-mesh. Maleic anhydride polypropylene (MAPP) was used as a coupling agent. Then, their resistance to screw and nail penetration was measured and compared according to the BS EN 1382 (2016) standard. With increasing particle size in all species, the resistance to screwing and nailing decreased significantly by about 2 to 13%. There were obvious differences between the resistance to screwing and nailing of the species, but these differences were not significant, and the resistances of the mixtures were near to the averages for these species.

We present a general strategy for constructing mechanically robust superlattices using monomicelle-encapsulated nanocrystals (MENCs) as building blocks. MENCs are created by encapsulating individual nanocrystals within micelles of poly(styrene-co-maleic anhydride), driven by hydrophobic interactions between styrene segments and native surface ligands. Concurrent hydrolysis of maleic anhydride moieties generates carboxyl groups that establish intramicelle hydrogen bonds (H-bonds), stabilizing MENCs in aqueous dispersion. Upon solvent evaporation, MENCs self-assemble into long-range-ordered, three-dimensional superlattices. Crucially, postassembly intermicelle H-bonding spontaneously fuses adjacent MENCs into a continuous, cross-linked architecture. This dual-level H-bonding imparts exceptional structural cohesion, yielding superlattices with elastic moduli of up to 18.73 GPa, far exceeding conventional superlattices stabilized by van der Waals or H-bonding interactions.

Conveyor belt idler rollers are vital for supporting and guiding conveyor belts, ensuring safe and efficient operations. In recent years, polymeric materials such as high-density polyethylene (HDPE) and polyamide 6 (PA6) have emerged as alternatives to steel in the fabrication of idler rollers, due to their lightweight and corrosion-resistant properties. However, their susceptibility to abrasion and fatigue limits their performance under high loads. This study was aimed at enhancing the thermo-mechanical and tribological properties of HDPE/PA6 and recycled HDPE/PA6 blends for idler roller body fabrication, compared to a reference industry formulation. Blends containing 80 wt% HDPE or re-HDPE and 20 wt% PA6 were melt-blended with 2 wt% polyethylene grafted with maleic anhydride (PE-g-MAH) as a compatibilizer. The addition of 15 wt% glass fibres (GF) to the compatibilized HDPE blend resulted in a 9 % increase in the heat deflection temperature (HDT), and reductions of 42 % and 29 % in the wear rate and coefficient of friction (COF), respectively, compared to the industry reference material. A similar trend was observed in the HDT, wear rate and COF of the 80 wt% re-HDPE blend, with the reduction in the wear rate more pronounced. Finite element simulations using Abaqus confirmed that the 7-inch outer diameter idler roller prototype made from 15 wt% GF reinforced 80 wt% HDPE blend had a lower maximum deflection of 0.054 mm, compared to that of the industry reference material (0.059 mm) under a 4889 N load, demonstrating improved structural rigidity. These results indicate that re-HDPE/PA6-GF composites offer a durable, lightweight, and corrosion-resistant alternative to conventional metallic rollers, with potential for extended service life and energy-efficient operation in bulk material handling systems.

The sluggish Diels-Alder reaction of perylene with maleic anhydride is accelerated by the addition of chloranil as an oxidant to form the fully aromatic benzoperylene derivative using this Clar variant. However, only moderate yields were obtained even for a large excess of chloranil, whereas high yields could be obtained by means of stepwise addition; this behavior resembles the substrate inhibition of enzymes and is discussed in terms of aggregation. The improved synthetic method could be generalized for various perylene biscarboximides and even for systems with anellated heterocycles. The method allows for the first time a double extension of perylene itself to coronene derivatives in one step. This offers the possibility of a very short synthesis of coronene.

ABSTRACTNew blends of poly(ethylene terephthalate) (PET) and bio‐based low‐density polyethylene (Bio‐LDPE) were developed and compatibilized with low‐density polyethylene grafted with maleic anhydride (LDPE‐g‐MA) in ratios of 70/30 and 50/50 wt%, with compatibilizer contents of 5, 7.5, and 10 phr (parts per hundred of resin). The blends were processed via twin‐screw extrusion followed by injection molding. Comprehensive characterization was performed, including rheological, chemical, mechanical, thermomechanical, thermal analyses, and morphological evaluation. The compatibilized blends exhibited a reduced melt flow index (MFI) and higher torque, indicating improved melt stability during processing. Impact tests revealed outstanding performance for the PET/Bio‐LDPE/LDPE‐g‐MA (50/50/10) blend, showing a remarkable 1970% increase in impact strength compared to the non‐compatibilized system. Scanning electron microscopy (SEM) analysis revealed enhanced phase dispersion and interfacial adhesion, with the formation of interfacial connections between the polymeric phases, confirming the compatibilizer's effectiveness in the PET/Bio‐LDPE/LDPE‐g‐MA blends and supporting the observed improvements in impact strength and elongation at break. While the elastic modulus, tensile strength, and hardness decreased relative to neat PET, elongation at break significantly increased, indicating improved ductility. The heat deflection temperature (HDT) exhibited a slight decrease compared to neat PET; however, this reduction was not significant. Differential scanning calorimetry (DSC) analysis revealed the influence of the compatibilizing agent on the crystallization of the PET fraction, associated with a reduction in crystallinity. These results demonstrate that the produced blends are promising in the polymer industry, such as the packaging sector.

The concept of heating the near-wellbore zone (NWZ) using activated aluminum alloys offers a novel approach to enhancing oil recovery. This article reviews research on the development of hydrocarbon-based solvent formulations for removing asphaltene–resin–paraffin deposits (ARPD) in the NWZ and restoring well productivity. A comprehensive analysis of ARPD composition enabled the selection of solvent systems tailored to specific deposit types. The efficiency of ARPD removal from the NWZ, downhole equipment, and oil gathering systems in heavy and highly viscous Kazakhstani crude oils was evaluated using hydrocarbon solvent blends (e.g., hexane–toluene, gasoline–o-xylene, o-xylene–hexane–1-hexene) with surfactants (polyoxyethylene sorbitan–maleic anhydride esters), atactic polypropylene (APP), and activated aluminum alloys. The developed formulations accelerated ARPD breakdown and reduced energy consumption. It has been established that the optimal concentration of APP (0.5 wt.%) provides up to 100% cleaning efficiency and increases dissolving capacity by 25–30% compared to traditional binary systems. Cleaning efficiency is driven by a thermochemical reaction between water and the aluminum alloy, 2Al + 6H2O → 2Al(OH)3 + 3H2↑ + 17 kJ, which depends on the alloy’s microstructure, grain boundary condition, and additive distribution. The exothermic effect of the reaction leads to the formation of a hot gas–steam–hydrogen mixture, where atomic hydrogen actively breaks down ARPD and increases the reservoir permeability by 2 to 4.5 times. Results show that a composite formulation of hexane–toluene–alloy–H2O2 (46.5:15:0.25:38.25) reduces the treatment time of ARPD-3 from 60 to 10 min while maintaining high efficiency at the level of 98.3%.

Thermoplastic desulfurized reclaimed rubber is a low-costand environmentallyfriendly material. However, its complex composition and severely reducedmolecular weight can impair the performance of rubber products whenblended with other rubbers. Silica is currently the primary fillerfor producing green tires, owing to its environmentally friendly comprehensiveperformance. However, achieving uniform dispersion of high silicacontent in nonpolar rubbers, such as styrene–butadiene rubber(SBR), remains challenging owing to the strong interactions amongpolar silica particles. Herein, desulfurized natural reclaimed rubber(NRR) was modified by simultaneous grafting with glyceryl methacrylateand maleic anhydride, which can form significantly stronger interactionswith polar silica via hydrogen bonding, improving the processing performanceand mechanical properties. Compared to ungrafted SBR/silica/NRR composites,the grafted SBR/silica/NRR composites improved the tensile strength(15.8%), elongation at break (33.8%), tear strength (2.4%), and modulusat 100% elongation (3.3%) while reducing fatigue heat generation.Through this cografting modification, the obviously reduced elongationat break caused by the addition of unmodified reclaimed rubber washighly improved. This modification strategy enables high-value reuseof reclaimed rubber.

Hexavalent chromium (Cr(VI)) contamination in water poses severe environmental and health risks, necessitating efficient and sustainable removal technologies. A water-based polyacrylic resin was synthesized via inverse emulsion polymerization using methyl methacrylate, acrylic acid, and maleic anhydride, thereby avoiding the use of organic solvents. Under optimal conditions (0.8 g dosage, pH 2, 318 K, 12 h), the resin achieves 98.73% Cr(VI) removal from 1 mg/L wastewater, following the pseudo-second-order kinetic model (R2 = 0.9927). Furthermore, the adsorption is well-fitted to the Langmuir model (R2 = 0.9911), yielding a calculated maximum adsorption capacity of 142.86 mg/g. FTIR analysis confirms chemisorption via Cr–O bond formation as the key mechanism. Thermodynamic analysis supports this chemisorption dominance, revealing an exothermic process (ΔH = 138.47 kJ/mol) with high spontaneity (ΔG < 0). Characterization via SEM/XRD shows the resin’s 3D porous structure maintains integrity post-adsorption. Significantly, acid–base elution enables high regeneration efficiency (> 93%) over 5 cycles without secondary pollution. These findings highlight the promising potential of the water-based polyacrylic resin as a macromolecular adsorbent for the efficient removal of Cr(VI) ions from wastewater, offering a viable solution for wastewater treatment.

Heterocyclic compounds remain cornerstones of contemporary drug discovery because their ring-embedded heteroatoms confer adaptable electronics, conformational flexibility, and a broad spectrum of biological activities. The skeleton structure of 4-thiazolidinone is present in many cytotoxically active compounds and is often used in the design of new antitumor agents. This study aimed to synthesize, characterize, and evaluate the anticancer potential of fifteen new (2-imino-4-oxo-1,3-thiazolidin- 5-yl)acetic acid derivatives. Compounds were synthesized using a consistent synthetic route involving a reaction between a thiourea derivative and maleic anhydride, which formed the thiazolidin- 4-one ring through cyclization. The compounds were then categorized into three sets based on the attached heterocyclic rings (tryptamine, thiazole, and 1,2,4-triazole). The NMR and X-ray analysis followed the synthesis. Apoptotic effects, cell cycle arrest, IL-6 suppression, docking, and dynamics simulations were conducted. Preliminary cytotoxic activity was tested on metastatic colorectal cancer (SW620) and human breast adenocarcinoma (MDA-MB-231) cell lines using the MTT assay. Compounds 5, 6, and 7 demonstrated notable selectivity indexes (4.73, 2.42, 4.16, respectively) and were further investigated for their mechanisms of action, revealing pro-apoptotic properties and the ability to induce cell cycle arrest. Additionally, compound 5 inhibited IL-6 secretion by 76%. in silico studies revealed the formation of an energetically stable complex between compound 5 and the EGFR crystal structure (min/- max binding affinities of -9.4|-8.0 kcal/mol, compared to the -7.71 kcal/mol for the native ligand). This preliminary study provides compelling data on synthesized derivatives, but more advanced testing is needed to assess their therapeutic value fully. Compared with earlier reports on related thiazolidinone scaffolds, the present derivatives exhibit improved potency, clearer selectivity, and mechanistic features consistent with EGFR inhibition and cytokine modulation. These findings validate (2-imino-4-oxo-1,3-thiazolidin-5-yl)acetic acid as a privileged core for cytotoxic lead generation and indicate that strategic substitution with either a tryptamine moiety (compound 5) or a 1,2,4-triazole ring (compound 7) is particularly advantageous. These compounds are promising EGFR-targeting anticancer candidates, warranting further investigation.

Maleic anhydride (MAnh) and its derivatives comprise a collection of underutilized monomer classes, each with unique reactivities and properties, which afford the design and synthesis of highly functional (co)polymers. This review explores the opportunities and limitations associated with maleic anhydride and its derivatives in conventional radical and controlled radical polymerization techniques. The potential of these monomers to create (co)polymers with desirable properties in advanced polymer design is highlighted.

We have developed a novel triple-responsive (pH/reduction/near-infrared (NIR) light) cross-linked polymer micelle PEG-P(LL/LL-LA)-PCL-IR820 for enhanced synergistic cancer therapy. This micelle was synthesized using a triblock amphiphilic polymer based on polylysine, functionalized with maleic anhydride (LA) as a cross-linking site and polycaprolactone (PCL) for encapsulating the anticancer drug doxorubicin (DOX). The photosensitizer IR820 was grafted onto PCL to enable photothermal and photodynamic effects under NIR irradiation. The DOX-loaded cross-linked micelles (DCMs) demonstrated exceptional stability under physiological conditions, effectively preventing premature drug release. Rapid DOX release was triggered by the intracellular high glutathione (GSH) level and acidic pH in tumor cells. Under NIR irradiation, DCM micelles exhibited significant photothermal and photodynamic effects, which markedly enhanced the cytotoxicity against B16 tumor cells. In B16 tumor-bearing mice, the DCM-treated group achieved superior tumor growth inhibition and prolonged survival under NIR irradiation compared to un-cross-linked micelles (DUCM) or free DOX, with minimal systemic toxicity. The tumor volume in the DCM + NIR group was significantly inhibited compared with other groups, reaching only about 300 mm3 within 15 days, while for the PBS-treated group, it reached approximately 1400 mm3. The survival rate of the DCM + NIR group was also significantly higher, with an over 70% survival rate within a 40-day observation period. This work presents a robust nanoplatform that combines stability, microenvironment responsiveness, and multimodal therapy, offering a promising strategy for targeted cancer treatment.

Incorporating recycled plastics into demanding automotive industry can boost the plastic waste recycling rate. While advancements have been made, challenges remain in enhancing the quality and applicability of recycled plastics. This work aims to develop pine wood flour and calcium carbonate reinforced recycled polypropylene (R-PP)/talc composites using extruder, followed by injection molding. Maleic anhydride modified polypropylene (MAPP) was added to strengthen the bonding of wood flour and (R-PP)/talc. The first step involved extruding wood flour, MAPP, and (R-PP)/talc, then crushing the extrudate into granules. Then the final composites were obtained by injection molding of calcium carbonate and the granulated samples. The properties of hybrid polymer composites were investigated by FTIR spectroscopy, density, mechanical tests (tensile, flexural, izod impact strength), heat deflection temperature (HDT) and Vicat softening temperature (VST). The tensile strength of wood flour and MAPP incorporated samples were improved compared to (R-PP)/talc based control sample and no significant change was observed with CaCO 3 addition. The flexural characteristic of all hybrid composites were enhanced, 15 wt% CaCO 3 resulted in higher flexural modulus among the composites. However, the elongation at break and impact strength showed decrement for filler incorporated composites. The HDT and VST of hybrid composites increased approximately 10°C and 20°C, respectively, compared to control sample, indicating an enhancement in thermal stability. Overall, the developed hybrid composites can be valuable for the recycling sector. In this context, the evaluation and adoption of recycled polypropylene could pave the way for a more sustainable future, aligning economic interests with environmental stewardship.

Flame retardant modified starch adhesive made by crosslinking with phosphorus containing citrate based polyamines has excellent boiling water resistance.

Sustainable route toward processing of polylactic acid/sawdust-based cellulose composites via grafting: Energy consumption during extrusion.