Search Results (483)

This study investigated the comparative effects of various maleic anhydride-grafted polymeric compatibilizers such as polyethylene-graft-maleic anhydride, polypropylene-graft-maleic anhydride, polyethylene(alt)-graft-maleic anhydride and poly(styrene-ethylene/butylene-styrene)-graft-maleic anhydride on the final properties of polypropylene (PP) carbon nanotube (CNT) composites. Polypropylene nanocomposites (PP-CNT) were prepared by melt mixing using a laboratory scale twin-screw extruder. The mechanical test results showed that the incorporation of CNTs along with various compatibilizers increased the tensile strength (10.3%) and tensile modulus (24.2%). The tensile modulus and yield stress of the PP-CNT nanocomposites were significantly higher than those of the pristine PP. Differential Scanning Calorimetry (DSC) analysis revealed that the addition of CNTs slightly increased the melting temperature of the crystallization peaks. In the compatibilized PP-CNT composites, the CNTs were well dispersed to enhance the onset of degradation and maximum decomposition temperatures. The frequency-dependent rheological behaviors of PP-CNT nanocomposites indicated that the storage modulus (G’), loss modulus (G”), and complex viscosity (η*) PP increased for the compatibilized system. The XRD results indicated that the addition of CNTs and compatibilizers slightly affected the crystalline nature of PP. Scanning electron microscopic images of the fractured surfaces presented in the micrographs showed the brittle nature of the surface morphology of PP-CNT nanocomposites. Full article

Starch–polyphenol complexes have attracted increasing attention as functional ingredients for improving the structural stability and reducing the glycemic potential of starch-based foods, yet their application in extruded fresh noodles remains insufficiently understood. In this study, chestnut starch–resveratrol complexes prepared by heat-moisture synergistic recrystallization treatment (CS-HMRT-Res) were incorporated into extruded fresh noodles, and their quality, structural characteristics, digestibility, and glycemic response were systematically evaluated. Compared with commercial wheat-based Regan noodles, CS-HMRT-Res noodles exhibited enhanced cooking stability (lower swelling and leaching) and improved texture (hardness, chewiness, tensile strength), with a markedly lower total color difference after cooking (ΔE = 1.8 vs. 6.5). SEM, FTIR and XRD indicated a more compact and ordered network; the relative crystallinity of cooked noodles increased to approximately 30.8%. In in vitro digestion, CS-HMRT-Res showed the lowest starch hydrolysis extent at 180 min (45.92%) and yielded a low predicted glycemic index of 53.35, compared with 70.65 for Regan noodles. Consistently, gavage studies in mice confirmed that HMRT-Res-chestnut starch produced the lowest postprandial blood glucose increment response (4.31 mmol/L). Molecular dynamics simulations further suggested that resveratrol could competitively occupy the α-amylase binding cavity and reduce starch accessibility to the enzyme. Overall, CS-HMRT-Res improved processing quality, structural integrity, and reduced glycemic potential, offering a structure-function framework for designing low-GI products. Full article

Polymer blends constitute a strategy for tailoring the properties of commercial polymers, leading to the development of materials designed for specific applications. In this work, the effect of the mixing sequence of the reactive compatibilizer styrene–acrylonitrile functionalized with epoxy groups (SAN-g-Epoxy) on the performance of poly(butylene terephthalate) (PBT)/acrylonitrile–butadiene–styrene (ABS) blends was investigated. PBT/ABS blends (60/40 wt%) were prepared by reactive extrusion in a twin-screw extruder followed by injection molding, incorporating five parts per hundred resin (phr) of SAN-g-Epoxy through different mixing sequences, aiming to understand how the processing order influences interfacial reactions, morphology, and the final properties of the material. The results indicated that SAN-g-Epoxy promotes reactive compatibilization between PBT and ABS, as evidenced by a significant increase in torque and complex viscosity, as well as by an increase in the intensity of the carbonyl band in the Fourier transform infrared spectroscopy (FTIR) spectra. By scanning electron microscopy (SEM), the presence of the compatibilizer resulted in a pronounced morphological refinement of the dispersed ABS phase, reducing the average particle size from approximately 4.34 µm to about 0.47–0.54 µm. Among the processing strategies, the route (PBT/SAN-g-Epoxy) + ABS exhibited the best mechanical performance under impact, reaching 206.7 J/m. However, the simultaneous mixing sequence PBT/ABS/SAN-g-Epoxy showed the best balance of properties, with gains of 203% in impact strength, 8.8% in elastic modulus, and 40.1% in heat deflection temperature (HDT) compared to neat PBT. The results indicate that PBT can be improved and tailored for engineering applications. Full article

Gravity casting and semi-solid extrusion were employed to prepare Mg₂Si-Al composites. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), EDS analysis, Vickers hardness testing, and tensile testing were used to compare the microstructures and mechanical properties of the two composites, aiming to clarify the effects of the fabrication processes and aging times on their microstructures and mechanical performance. The findings show that semi-solid extrusion converts dendritic α-Al into spherical or ellipsoidal grains (60 ± 25 μm) and induces the spheroidization of Mg₂Si reinforcing phases (29 ± 12 μm). Vickers hardness data show that both composites exhibit a rise-and-fall hardness trend with an increasing aging time, reaching a maximum at 8 h. At this aging stage, the semi-solid extruded composite has a Vickers hardness of 214 ± 32.71 HV, 22.99% higher than that of the gravity-cast composite under the same treatment. Tensile tests demonstrate that the semi-solid extruded composite attains its best tensile strength (254 MPa) and elongation (3.26%) at 8 h of aging. Compared with the semi-solid extruded composites aged for 4 h and 16 h, the 8 h-aged sample exhibits 32.30%/49.41% higher tensile strength and 52.34%/38.72% higher elongation, respectively. After 8 h of aging, the semi-solid extruded composite shows a 59.75% increase in tensile strength and an 88.44% increase in elongation compared with the gravity-cast composite. Full article

Background/Objectives: Hot-melt injection molding (HMIM) was evaluated as a solvent-free process for the preparation of glibenclamide (GLB), a poorly soluble BCS Class II drug, glassy solutions with the objective of improving dissolution and bioavailability for diabetes. Methods: GLB was blended at a concentration of 10% w/w with PVP K25, PVP VA64, and Soluplus^® (SOL) matrices. The miscibility of the GLB–polymer systems (matrices) was calculated based on the Hansen solubility parameters and validated using differential scanning calorimetry (DSC) analysis. The HMIM extrudates were milled into granules and analysed for their solid-state properties (DSC, XRPD, FTIR, and SEM studies), and flow properties. The produced granules were compressed into immediate release tablets and assessed for in vitro performance, stability, and in vivo bioavailability using 20 healthy male Sprague Dawley rats. Results: Findings revealed the formation of single-phase glassy solutions, specifically for PVP VA64 and SOL, which also exhibited advantageous manufacturing and extrudate clarity. The glassy solution formulations showed considerably improved dissolution characteristics compared with the crystalline GLB and the commercial product. The glassy solution formulations displayed fast drug release for PVP K25 and PVP VA64, and biphasic drug release for SOL. Stability testing confirmed the capability of PVP VA64 and SOL to maintain GLB in a molecularly dispersed, amorphous state for 12 months. The in vivo assessment revealed an increase in relative bioavailability to 246.3% and 124.5% for the SOL and PVP VA64 formulations when compared to the commercial formulation. Conclusions: Overall, the findings demonstrate the potential of HMIM-processed glassy solutions, especially those prepared using SOL, as promising platforms for promoting oral delivery of the poorly soluble antidiabetic GLB. Full article

Fe₂O₃-reinforced PMMA nanocomposites were prepared by melt blending using a twin-screw micro-extruder. Fixed Fe₂O₃ loading of 2.5 wt.% was employed, and mixing times of 6 and 12 min were used to obtain nanocomposites with different dispersion characteristics. The structural and morphological properties of the samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), while their thermal degradation behavior was evaluated by differential thermal and thermogravimetric analyses (DTA/TG). The activation energies of thermal degradation were calculated using the Kissinger, Takhor, and Augis–Bennett methods. Increasing the mixing time improved nanoparticle dispersion and reduced agglomeration. The addition of Fe₂O₃ slightly decreased the characteristic degradation temperatures of PMMA, while the activation energy increased for the better-dispersed sample. The results indicate that interfacial interactions and particle dispersion play important roles in the thermal degradation behavior of PMMA/Fe₂O₃ nanocomposites. Full article

The topic of improving the strength and performance properties of secondary polyamide materials as part of their functional modification is a very relevant area of expanding the possibilities of secondary use of plastic waste. The article aims to conduct a systematic study of the combined modification of polyamide waste agglomerate by six different types of carbon materials to improve their technological and strength properties. PA6 waste agglomerate from polyamide clothing items, tights, socks, and various carbon materials were studied: masterbatch for polyamides MW-PA CB10, brown coal humic substances, coke residue from pyrolysis, a mixture of plastic waste, and finely dispersed coal enrichment waste. A sustainable polymer composite based on a modified agglomerate of PA6 waste was obtained by extruding pre-prepared raw materials in a single-screw extruder. The structural and morphological analysis of the studied carbon materials showed that, within the framework of the combined modification of polyamide-6 waste agglomerate, they should perform different functions related to their distinct morphology and chemical composition. Thus, humic substances can act as functional modifiers and compatibilizers due to their nanodispersity and a wide range of active chemical groups. In contrast, coke residue from pyrolysis and coal enrichment waste will act as a functional filler to improve the complex strength properties of sustainable polymer composites. As part of a study on the effect of modifying polyamide-6 waste agglomerate by carbon materials on its complex technological characteristics, it was demonstrated that humic substances enhance sustainable polymer composite’s technological properties by increasing the melting temperature and melt flow index while reducing density. The increase in the functional effect of humic substances is due to the growth of a wide range of active chemical groups (hydroxyl, carboxyl, peptide). During the initial oxidation of brown coal, the coke residue from pyrolysis and coal enrichment waste served as a filler, increasing the sustainable polymer composite’s density and melt flow index. As part of the study of the effect of modification by carbon materials on the complex strength characteristics of polyamide-6 waste agglomerate, it was shown that all carbon materials studied, except for coke residue, improve the strength characteristics of polyamide-6 waste agglomerate. The optimal content of different types of humic substances is 0.5% wt., while the sustainable polymer composite’s impact strength and breaking stress during bending increase with the increase in the functionalization of humic substances during the oxidation of brown coal. It has been shown that the combination of small amounts of oxidized humic substances at the level of 0.5% by weight, as a functional additive with a masterbatch MW-PACB10 in an amount of 2–3.5%wt., provides materials with increased impact strength from 23 to ~48 kJ/m² and bending fracture stress from 115 to ~135 MPa, which allows returning secondary PA6 waste to the “traditional areas of primary PA6” in the manufacture of general technical parts and products. Full article

The Al–Cu–Mg–Ag alloys have excellent specific strength, good heat resistance and have a wide range of applications in the aerospace and automotive industries. However, industrial production of such alloys is a great challenge owing to the addition of Ag, which limits their widespread application. In this work, the industrial continuous cast and continuous extrusion (Conform) processes were employed to prepare Al–5Cu–0.4Mg–0.1Zr (–0.4Ag) alloys, and the effects of Ag addition on the microstructural characteristics and mechanical properties during processing and heat treatment were investigated. The results indicated that Ag addition significantly refined grain size, increased high-angle grain boundary fraction and grain orientation difference in as-cast Al–5Cu–0.4Mg–0.1Zr (–0.4Ag) alloys, and suppressed excessive grain coarsening during homogenizing annealing. During Conform, Ag further refined grain size, increased subgrain number and enhanced grain orientation difference in extruded alloys. For the aging heat treatment, the T6 process demonstrated superior strengthening effects compared to the T5 process. Following T6 treatment, Ag promoted efficient and uniform precipitation of the Ω (Al₂CuMgAg) phase and then significantly enhanced peak hardness (160 HV) and tensile strength (511.46 ± 2.06 MPa). Additionally, Ag accelerated second-phase dissolution throughout the entire process and produced finer, denser ductile dimples on tensile fracture surfaces to gain good strength–ductility balance. Full article

Maltodextrin is the most commonly used carbohydrate ingredient in Food for Special Medical Purposes (FSMP). However, growing evidence suggests that it may trigger intestinal inflammatory responses. Replacing maltodextrin with pre-hydrolyzed rice extrudates represents a viable approach to eliminate such adverse effects. Accordingly, this study prepared pre-hydrolyzed rice extrudates with different dextrose equivalent (DE) values and investigated their impact on the physicochemical properties of emulsion-type FMSP containing carbohydrates, casein, and soybean oil with increasing addition levels. The emulsion particle size of pre-hydrolyzed rice extrudates with different DE values showed a gradual upward trend, while the zeta potential gradually decreased. As the DE value increased, its influence on the zeta potential and viscosity of the emulsion diminished. However, samples with lower DE values contributed positively to reducing the centrifugal sedimentation rate of the emulsion, which was mainly attributed to their higher viscosity. In contrast, the turbidity and adsorption rate of emulsion samples with higher DE values were less affected by the addition level. Through turbiscan stability index and multi-index comprehensive evaluation, the optimal addition levels for pre-hydrolyzed rice extrudates with different DE values were obtained. The findings provide important insights for promoting the application of pre-hydrolyzed rice extrudates as a substitute for maltodextrin in FMSP. Full article

Background/Objectives: Poor aqueous solubility of active pharmaceutical ingredients (APIs) remains a critical barrier to effective oral formulation. This study investigated the production of ketoprofen amorphous solid dispersions (ASDs) via hot melt extrusion (HME) using hydrophilic carriers and surfactants to enhance solubility and dissolution. Methods: ASDs were prepared by the fusion method employing mannitol or polyethylene glycol (PEG) 4000 hydrophilic carriers and further modified by addition of poloxamer 188 or poloxamer 407 as surfactants. Solubility was evaluated, and the best performing formulations were selected for HME to assess the effect of extrusion parameters (temperature, screw speed and re-extrusion) on API solubility and dissolution. Selected ASD extrudates were formulated into tablets and capsules and further tested. Results: Ternary ASDs exhibited higher solubility than their binary counterparts. The combinations of high-concentration hydrophilic carrier (mannitol or PEG 4000) and poloxamer 407 proved the most effective. The HME-produced ASDs showed superior solubility compared to the simple fusion method, with temperature being the most critical processing parameter, while screw speed and re-extrusion were carrier dependent, enhancing solubility for mannitol-based ASDs but not for PEG 4000; re-extrusion also led to mild color changes and technological issues preventing further processing. The selected ASD extrudates were successfully formulated into tablets and capsules with good physical characteristics and dissolution profiles. Conclusions: These findings demonstrate the need to further investigate the potential of re-extrusion strategies and surfactant-enhanced ASD systems for improving the oral delivery of poorly soluble drugs. Full article

This research aims to develop a chitosan-coated, TH-loaded nanobilosomal gel (CH-TH-BG) to magnify the transdermal delivery and anti-inflammatory efficacy of thymol (TH) for the management of rheumatoid arthritis (RA). Initially, chitosan-coated, TH-loaded bilosomes (CH-TH-BLs) were prepared and optimized by Box–Behnken design. The optimized CH-TH-BLs exhibited enhanced entrapment efficiency (83.52%) and a positive zeta potential (+36.3 mV). Further, the optimized lyophilized CH-TH-BLs were incorporated into the carbopol gel (CH-TH-BG) and characterized thoroughly. The CH-TH-BG exhibited superior pharmaceutical properties, including high drug content (98.65 ± 1.43%), optimal viscosity (10,400 ± 12.6 cps), excellent spreadability (5.33 ± 0.15 cm), extrudability, and a slightly acidic pH (5.40 ± 0.10), which resembles the pH of human skin. In vitro drug release revealed that the developed gel exhibited a biphasic release pattern, with a rapid release followed by sustained release. Notably, ex vivo results revealed a ~2.0-fold increase in permeation flux and a ~2.8-fold increase in skin retention compared to the TH solution. In vivo results confirmed a significant reduction in paw edema and pro-inflammatory biomarkers (TNF-α and IL-6), alongside recovery of body weight and ankle joints. In conclusion, the CH-TH-BG is a transformative transdermal platform for effective management of RA. Full article

This work investigates the effect of recycling on the rheological and thermal properties of petroleum-based polyester nanocomposites. PET and PBT are used widely in the automobile and packaging industries, and there is a growing need for effective ways to utilize recycled polyesters. The melt mixing method was used to prepare the nanocomposites using a twin-screw extruder. After recycling, the rheological properties of the PBT nanocomposite remained stable, as the degradation of PBT chain was low due to the presence of MWCNT and molecular chain flexibility. In contrast, the complex viscosity of PET recycled nanocomposite decreases significantly because the high processing temperature of 280 °C led to substantial polymer chain scission and network breakdown. Due to the presence of MWCNT, PET and PBT nanocomposites show higher thermal stability than pure and recycled nanocomposites. The recycling of PET and PBT nanocomposites demonstrated potent thermal stability under inert and air/oxidative atmospheres. These results indicate that the effect of recycling strongly depends on the polymer matrix: while PET-based nanocomposites exhibit notable reductions in rheological properties after recycling, PBT-based nanocomposites retain stable rheological and thermal performance due to MWCNT reinforcement. The enhancement in this research could make the recycled materials valuable for the automotive industry. Full article

This study investigated the effects of different types and ratios of plasticizers on the fabrication and properties of hot-melt-extruded filaments and fused deposition modeling (FDM) three-dimensional printed tablets containing theophylline (THEO). Polyethylene glycol (PEG) 1500 and stearic acid (SA) were used as plasticizers to prepare THEO-loaded filaments in a hydroxypropyl cellulose matrix via hot melt extrusion (HME), which were subsequently fabricated into tablets using an FDM 3D printer. The physicochemical properties of the filaments and printed tablets were evaluated using scanning electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Drug release behavior was assessed using four tablet formulations (T1–T4) with different plasticizer types and ratios. All fabricated filaments exhibited sufficient hardness and flexibility for reliable 3D printing, and solid-state analyses confirmed partial molecular dispersion of THEO within the polymer matrix. In dissolution studies, PEG-containing formulations showed faster drug release than SA-based formulations, while all 3D-printed tablets achieved approximately 80% drug release within 6 h. Overall, this study demonstrates that the combined use of HME and FDM-based 3D printing, together with rational plasticizer selection, enables the development of personalized pharmaceutical tablets with tunable immediate and sustained drug release profiles. Full article

Lycopene is a potent antioxidant carotenoid with significant health-promoting properties. However, its practical application is limited by poor water solubility. This study aimed to enhance lycopene dispersibility through the development of solid dispersions obtained by hot-melt extrusion (HME). Polymeric carriers composed of polyvinylpyrrolidone K30 (PVP K30), phosphatidylcholine, and xylitol were designed to achieve optimal processing conditions and thermal stability. Nine formulations containing 10–30% lycopene were prepared and characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FT-IR), and dispersibility testing. TGA confirmed the thermal stability of lycopene at the extrusion temperature (150 °C). DSC and XRPD analyses indicated partial amorphization of lycopene in the extrudates, while FT-IR spectra revealed molecular interactions between lycopene and carrier components, particularly hydroxyl and carbonyl groups. Among the tested systems, the formulation containing PVP K30 and xylitol without phosphatidylcholine exhibited the highest dispersibility (1.0484 mg/mL after 3 h). Dispersibility decreased with increasing lycopene content. These findings demonstrate that HME is an effective technique for producing partially amorphous lycopene dispersions with improved dispersibility, and that polymer–polyol systems are particularly promising carriers for enhancing lycopene bioavailability. Full article

Avocado processing generates seed by-products rich in dietary fiber that can be upcycled into functional ingredients. This study modified and characterized avocado seed flour via extrusion and enzyme-assisted wet-milling, as well as evaluated its use in wheat bread. The flour was fractionated, and fraction 2 (F2) was selected based on techno-functional performance; it was tested in its non-extruded (NEF2) and extruded (EF2) forms. Breads were prepared by replacing 5% of wheat flour with NEF2 and EF2 (NEB and EB, respectively). Compared with NEF2, EF2 had an 81% higher water absorption index (WAI) and an 18% higher oil absorption index (OAI). Extrusion reduced antioxidant activity ~1.6-fold, consistent with an ~85% decrease in acetogenin content, indicating thermo-mechanical degradation of bioactives linked to bitterness. Analyses were conducted in triplicate (p < 0.05). By day 3, crumb hardness increased (EB: 9.65 N; NEB: 6.04 N; control: 5.49 N). In a test with 106 consumers, aroma scores improved for NEB (8.00, IQR 7.00–8.00) and EB (7.00, IQR 5.00–8.00) versus the control (6.00, IQR 4.00–7.00), while overall acceptability, texture, color, and appearance did not differ. These results support EF2 as a functional upcycled ingredient that enhances hydration and aroma, reduces bitterness, and maintains consumer acceptance, aligning with circular economy and clean-label goals. Full article