Extrusion Research Articles

Mechanical, Thermal and Morphological Study of Bio-Based PLA Composites Reinforced with Lignin-Rich Agri-Food Wastes for Their Valorization in Industry.

This study investigates the performance of different poly(lactic acid) (PLA) composites incorporating agri-food waste additives and commercial lignin, comparing their properties with those of virgin PLA. The following composites were prepared using a single-screw extruder: PLA with 20% rice husk, PLA with 20% wheat straw and PLA with 20% olive pit. Additionally, PLA was blended with commercial lignin at the maximum feasible proportion using the same methodology. The resulting composites were injection-molded into specimens for analysis of their mechanical, thermal and morphological behavior. The primary objectives were to assess the dispersion of the additives within the PLA matrix and to evaluate the mechanical properties of the composites. The results indicate that the addition of high percentages of agricultural residues does not significantly compromise the mechanical properties of the composites. Notably, in the case of the PLA with 20% rice husk composite, the elastic modulus surpassed that of virgin PLA, despite the evident heterogeneity in filler particle sizes. It was feasible to incorporate a higher percentage of agricultural residues compared to commercial lignin, attributed to the larger volume occupied by the latter.

Peroxide free radical grafting of maleic anhydride onto polyethylene under high melt temperature: A comprehensive approach

“Flash Reactive Extrusion” under very high temperatures (T=200–420°C) allowed to graft maleic anhydride onto polyethylene (PE) without the use of conventional free radical initiators such as peroxides. Herein, the use of unusual temperatures induced the formation of radicals through degradation/chain scission of the PE backbone and the latter radicals were able to react with maleic anhydride (MA) and yielding a MA grafting degree close to 1.4 wt% at 390°C. Moreover, the MA grafting mechanistic scheme was deeply discussed with the help of 1H NMR and 13C NMR analysis and it was pointed out that β-scissions reactions are favoured in comparison with the cross-linking ones at very high temperatures for the thermal initiation step with a MA grafting mainly onto the PE side chain.

A Promising Recycling Strategy via Processing Polypropylene/Recycled Poly(ethylene terephthalate): Reactive Extrusion Using Dual Compatibilizers.

Enhancing interfacial adhesion in polypropylene (PP)/recycled polyethylene terephthalate (rPET) blends is crucial for the effective mechanical recycling of these commercial plastic wastes. This study investigates the reactive extrusion of PP/rPET blends using a dual compatibilizer system comprising maleic anhydride grafted polypropylene (PP-g-MA) and various glycidyl methacrylate (GMA)-based compatibilizers. The effects of backbone structure and reactive group on the morphological, mechanical, and thermal characteristics were systematically studied. This study sheds light on the effective compatibilization mechanisms using characterization methods such as Fourier Transform Infrared Spectroscopy (FTIR) and morphological analyses (SEM). The results indicate that GMA-based compatibilizers play a bridging role between rPET and PP-g-MA, resulting in improved compatibility between the blend components. A combination of 3 phr PP-g-MA and 3 phr ethylene-methyl acrylate glycidyl methacrylate terpolymer (EMA-GMA) significantly improves interfacial adhesion, leading to synergistic enhancements of mechanical performance of the blend, up to 217% and 116% increases in elongation at break and impact strength, respectively, compared to the uncompatibilized sample. Moreover, a significant improvement in onset temperature for degradation is observed for the dual compatibilized sample, with 40 °C and 33 °C increases in onset temperature relative to the uncompatibilized and the single compatibilized samples. These findings underscore the immense potential of tailored multi-component compatibilizer systems for upgrading recycled plastic waste materials.

Prediction of Mechanical Properties of Nano-Clay-Based Biopolymeric Composites.

An understanding of the mechanical behavior of polymeric materials is crucial for making advancements in the applications and efficiency of nanocomposites, and encompasses their service life, load resistance, and overall reliability. The present study focused on the prediction of the mechanical behavior of biopolymeric nanocomposites with nano-clays as the nanoadditives, using a new modeling and simulation method based on Comsol Multiphysics software 6.1. This modeling considered the complex case of flake-shaped nano-clay additives that could form aggregates along the polymeric matrix, varying the nanoadditive thickness, and consequently affecting the resulting mechanical properties of the polymeric nanocomposite. The polymeric matrix investigated was biopolyamide 11 (BIOPA11). Several BIOPA11 samples reinforced with three different contents of nano-clays (0, 3, and 10 wt%), and with three different nano-clay dispersion grades (employing three different extrusion screw configurations) were obtained by the compounding extrusion process. The mechanical behavior of these samples was studied by the experimental tensile test. The experimental results indicate an enhancement of Young's modulus as the nano-clay content was increased from 0 to 10 wt% for the same dispersion grades. In addition, the Young's modulus value increased when the dispersion rate of the nano-clays was improved, showing the highest increase of around 93% for the nanocomposite with 10 wt% nano-clay. A comparison of the modeled mechanical properties and the experimental measurements values was performed to validate the modeling results. The simulated results fit well with the experimental values of Young's modulus.

Assessing the Correlation Between the Physico-Mechanical Characteristics and Microstructure of Reclaimed Carbon Dust Reinforced ABS Polymer Composite in the Extrusion Process

ABS polymer has limited stiffness and will fracture upon reaching this limit. Reinforcing ABS with reclaimed carbon dust (rCD) from CFRP waste, which has superior stiffness in both compression and tension, can prevent this failure. This study evaluates the impact of varying rCD filler content and screw extruder speeds on the physico-mechanical properties of the composite. rCD content ranges from 0 wt.% to 40 wt.% and screw speeds of 20 rpm and 40 rpm are used. The rCD was sieved and its quality was verified using particle size analysis (PSA), field emission scanning electron microscopy with energy dispersive X-ray (FESEM-EDX), and X-ray diffraction (XRD) before composite fabrication in a single screw extruder. The physico-mechanical properties, including tensile strength, Young’s modulus, and density, were tested using a universal testing machine (UTM) and Archimedes technique. All samples appeared undistorted prior to UTM evaluation. Results indicated that composites processed at 40 rpm with 40 wt.% rCD exhibited superior physico-mechanical properties compared to those processed at 20 rpm. Fractography of tensile fracture samples showed well-dispersed rCD within the ABS matrix, with minimal large pores at 40 rpm. Additionally, the highest tensile strength (31.48 MPa) and Young’s modulus (1.603 GPa) indicated good dispersion of rCD and strong interfacial bonding between the matrix and fiber. Thus, a 40 rpm screw speed is more effective for mixing ABS/rCD composites. In conclusion, rCD was successfully reclaimed and integrated into ABS, resulting in a composite with enhanced strength properties suitable for assistive medical device application.

Revolutionizing Biomass Processing: The Design and Functionality of an Innovative Extruder for Sugarcane Bagasse Milling Pretreatment

Milling pretreatment is a crucial step in the bioconversion of lignocellulosic biomass such sugarcane bagasse because it facilitates access to cellulose for subsequent chemical treatments. However, most experiments have been conducted at the laboratory scale, where it has been identified that high energy is required for the processing of biomass. For this reason, it is proposed to implement the screw extruder technique for the processing of cellulose. This article focuses on the characteristics, types, and applications of milling pretreatment for sugarcane bagasse, with a particular emphasis on its role in lignin removal and the milling design. Milling pretreatment reduces the particle size of lignocellulose biomass through compression shear and tearing mechanisms, which enhances the accessibility of cellulose and hemicellulose to enzymes and chemicals, thereby improving the efficiency of bioconversion processes. Innovative mathematical modeling, a mechanical design in a CAD application, and an FEA analysis of the milling pretreatment equipment are presented, providing insights into the design and optimization of milling pretreatment processes. This article presents an innovative potential system for milling pretreatment in sugarcane bagasse for the production of bioethanol, heat and power, and other value-added products, contributing to a more sustainable and circular economy.

3D printed tinidazole tablets coupled with melt-extrusion techniques for formulating child friendly medicines

This study investigates the feasibility of fabrication of poly(1-vinyl-2-pyrrolidone) (Kollidon®25)-mediated filaments for producing tinidazole (TNZ)-loaded, customizable, child-friendly tablets (with varying shapes and sizes) using hot melt extrusion (HME) coupled with fused deposition modeling (FDM) technology. Kollidon®25, chosen for its ability to enhance the dissolution of TNZ (a BCS Class II drug), was evaluated for polymer-drug compatibility through Hansen solubility, polarity, and interaction parameter analyses, confirming good miscibility and affinity between TNZ and Kollidon®25. Placebo- and TNZ-loaded filaments were prepared in different ratios using HME, followed by the development of 3D-printed tablets via FDM. The fabricated batches of placebo and TNZ-loaded 3D tablets were characterized, and it was found that they had an average weight variation of 270.41 ± 7.44 mg and 270.87 ± 9.33 mg, hardness of 155.01 ± 11.79 N and 265.3 ± 7.62 N, and friability of 0.1583 ± 0.0011 % and 0.2254 ± 0.0013 %. Amorphization was confirmed by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) analysis. Scanning electron microscopy (SEM) revealed a layer-by-layer pattern with tiny fractures on the tablet surfaces, which enhanced media penetration, resulting in improved dissolution profiles. The TNZ release profile showed complete 100 % release within 2.0 h in a gastric acidic medium. These findings support the potential of Kollidon®25 to create customizable, child-friendly, 3D-printed dosage forms with different shapes and sizes for TNZ delivery, offering a unique approach to paediatric medications.

Effects of Carbon Fiber Content on the Crystallization and Rheological Properties of Carbon Fiber-Reinforced Polyamide 6.

Carbon fiber (CF)-reinforced polyamide 6 (PA6) composites have an excellent performance, attributed to properties such as light quality, high strength, and vibration reduction, and they are widely used in fields such as aerospace and transportation. Four kinds of carbon fiber-reinforced polyamide 6 (CF/PA6) composite pellets with carbon fiber contents of 20, 30, 40, and 50 wt.% were prepared using twin screw extrusion. The results were characterized using a simultaneous thermal analyzer, capillary rheometer, electronic universal material testing machine, and scanning electron microscope (SEM); their crystallization, rheological behavior, mechanical properties, surface structure, etc., were studied. DSC results indicate that an increase in carbon fiber content enhances the thermal stability of CF/PA6 and narrows the crystallization window but has a minor effect on the molecular chain diffusion time. The crystallinity reaches its maximum at a carbon fiber content of 40 wt.%, reaching 55.16%. The steady-state rheological behavior reveals that CF/PA6 behaves as a pseudoplastic fluid, exhibiting shear-thinning behavior. When the carbon fiber content is 40 wt.%, the power law exponent (n) reaches its maximum, and the consistency coefficient (K) decreases by 300 Pa⋅sn compared to the 30 wt.% content. With increasing temperature, n increases while K decreases. SEM observations reveal that samples with carbon fiber contents of 20 wt.% and 40 wt.% exhibit better fiber dispersion and orientation. However, the interfacial bonding strength is superior in the 40 wt.% sample. When the carbon fiber content reaches 50 wt.%, significant injection molding defects occur at the clamping end, leading to extensive matrix tearing during tension testing.

Van der Waals interactions enhanced multiple-times all-waste-recycled triboelectric nanogenerator for ultra-high lifetime stability

To mitigate the ever-increasing waste problem, utilization of recycled waste to fabricate energy harvesting devices has emerged as a propitious alternative. Despite several efforts, it is still a daunting challenge to sustain the properties of recycled-plastic-waste after multiple rounds of recycling. We address the above challenges by developing an industry-viable universal framework to recycle plastic-waste multiple-times without significant degradation in its properties. A multiple-times all-recycled triboelectric nanogenerator (MR-TENG) was demonstrated with high performance and record-high overall operational lifetime stability for 5 million cycles of mechanical impact. To the best of our knowledge, this is the first report of a nanogenerator made completely from recycled mixed-plastic-waste, which can sustain its energy-harvesting performance even after ten rounds of recycling. The multiple-times recyclability can be attributed to the improved van der Waals interactions between the polymeric blends at the macromolecular level facilitated by incorporating a mixed-plastic waste-derived compatibilizing agent, which is validated by molecular dynamics simulation. The adopted industry-viable reactive extrusion to fabricate the materials facilitates easy adaptability and commercialization. The practical application was demonstrated by utilizing it for deep learning-enabled MR-TENG-based advanced cognitive waste sorting and segregation, facilitating digitalized-waste-management, thus facilitating a major step towards upcycling of plastic-waste for circular economy.

The comparison of melt technologies based on mesoporous carriers for improved carvedilol dissolution

High-shear (HS) melt granulation and hot melt extrusion (HME) were compared as perspective melt-based technologies for preparation of amorphous solid dispersions (ASDs). ASDs were prepared using mesoporous carriers (SyloidⓇ 244FP or NeusilinⓇ US2), which were loaded with carvedilol dispersed in polymeric matrix (polyethylene glycol 6000 or SoluplusⓇ). Formulations with high carvedilol content were obtained either by HME (11 extrudates with polymer:carrier ratio 1:1) or HS granulation (6 granulates with polymer:carrier ratio 3:1).DSC and XRD analysis confirmed the absence of crystalline carvedilol for the majority of prepared ADSs, thus confirming the stabilizing effect of selected polymers and carriers over amorphous carvedilol. HME produced larger particles compared to HS melt granulation, which was in line with better flow time and Carr index of extrudates. Moreover, SEM images revealed smoother surface of ASDs obtained by HME, contributing to less obstructed flow. The rougher and more porous surface of HS granules was correlated to larger granule specific surface area, manifesting in faster carvedilol release from SyloidⓇ 244FP-based granules, as compared to their HME counterparts. Regarding dissolution, the two HS-formulations performed superior to pure crystalline carvedilol, thereby confirming the suitability of HS melt granulation for developing dosage forms with improved carvedilol dissolution.

Additive manufacturing of TPU devices for genital herpes treatment with sustained acyclovir release

The treatment of recurrent genital herpes typically involves daily doses of acyclovir for extended periods. Additive manufacturing is an intriguing technique for creating personalised drug delivery systems, which can enhance the effectiveness of treatments for various diseases. The vaginal route offers a viable alternative for the systemic administration of drugs with low oral bioavailability. In this study, we produced different grades of thermoplastic polyurethane (TPU) filaments through hot-melt extrusion, with acyclovir concentrations of 0%, 10%, and 20% by weight. We used fused filament fabrication to manufacture matrix-based devices, including intrauterine devices and intravaginal rings. Our results, obtained through SEM, FTIR, and DSC analyses, confirm the successful incorporation of acyclovir into the matrix. Thermal analysis reveals that the manufacturing process alters the organization of the TPU chains, resulting in a slight reduction in crystallinity. In our in-vitro tests, we observed an initial burst release on the first day, followed by sustained release at reduced rates for up to 145 days, demonstrating their potential for long-term applications. Additionally, cytotoxicity analysis suggests the excellent biocompatibility of the printed devices, and biological assays show a remarkable 99% reduction in HSV-1 replication. In summary, TPU printed devices offer a promising alternative for long-term genital herpes treatment, with the results obtained potentially contributing to the advancement of pharmaceutical manufacturing.

Scalability of API-Loaded Multifilament Yarn Production by Hot-Melt Extrusion and Evaluation of Fiber-Based Dosage Forms.

Fiber-based technologies are widely used in various industries, but their use in pharmaceuticals remains limited. While melt extrusion is a standard method for producing medical fibers such as sutures, it is rarely used for pharmaceutical fiber-based dosage forms. The EsoCap system is a notable exception, using a melt-extruded water-soluble filament as the drug release trigger mechanism. The challenge of producing drug-loaded fibers, particularly due to the use of spinning oils, and the processing of the fibers are addressed in this work using other approaches. The aim of this study was to develop processes for the production and processing of pharmaceutical fibers for targeted drug delivery. Fibers loaded with polyvinyl alcohol and fluorescein sodium as a model drug were successfully prepared by a continuous melt extrusion process and directly spun. These fibers exhibited uniform surface smoothness and consistent tensile strength. In addition, the fibers were further processed into tubular dosage forms using a modified knitting machine and demonstrated rapid drug release in a flow cell.

Biopolymer Hydroxypropyl Methylcellulose-Based Filaments Prepared by Hot-Melt Extrusion Suitable for Fused Deposition Modeling 3D Printing of Personalized Capsules

Biopolymer Hydroxypropyl Methylcellulose-Based Filaments Prepared by Hot-Melt Extrusion Suitable for Fused Deposition Modeling 3D Printing of Personalized Capsules

High-strength, impact-resistant PP/PTFE composite foam with enhanced surface appearance achieved through mold-opening microcellular injection molding

Poor surface appearance and decreased mechanical performance are critical factors limiting the broad application of Microcellular injection molding (MIM) in foamed polymer products. Herein, in-situ polytetrafluoroethylene (PTFE) nanofibrils reinforced polypropylene (PP) foams with high strength, impact resistance, and enhanced surface quality were prepared by mold opening microcellular injection molding (MOMIM). PTFE nanofibers with different diameters were introduced into the PP matrix via twin screw extrusion and significantly enhanced the crystallinity and viscoelasticity of the PP matrix with the enhancement being more pronounced for the finer PTFE fibers. High-density oriented cellular structures were formed in the MOMIM PP/PTFE foams owing to the heterogeneous nucleation of PTFE and the stretching effect of the mold opening process. The optimum MOMIM PP/PTFE foam fabricated possesses a high cell orientation angle close to 90° and a large cell aspect ratio of 5.3, which reached a 34.37 % increase in tensile strength and a 73.08 % increase in impact strength owing to the synergetic effects of the PTFE network and the highly oriented fine cell structure, which effectively dissipated the tensile stress and impact stress by cell wall twisting and folding deformation. Furthermore, the MOMIM PP/PTFE foam showed a significantly enhanced surface quality compared to the MIM foam due to the reduced dragging flow in MOMIM, which greatly hindered cell rupture on the foam surface. Therefore, this work provides insights into the MOMIM of polymer composites containing fibrous fillers and the enhancement of tensile properties, impact resistance, and surface quality of foam products.

Kühlsystem für die kunststoffadditive Fertigung

Abstract Screw extrusion additive manufacturing (SEAM) is an additive manufacturing process in which plastic granulate is melted and extruded using a screw extruder. In contrast to filament-based processes, this enables higher output rates and a greater variety of materials. One of the main challenges is the efficient cooling of the extrudates. An optimized cooling system is presented and its application potential demonstrated.

Performance Enhancement of Biopolyester Blends by Reactive Compatibilization with Maleic Anhydride-Grafted Poly(butylene succinate-co-adipate).

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a very promising biodegradable copolyester of high interest in food packaging. Its inherent brittleness and narrow processing window make it necessary to blend it with flexible biopolyesters, such as poly(butylene succinate-co-adipate) (PBSA). However, the resultant biopolyester blends are thermodynamically immiscible, which impairs their performance and limits their applications. This study is the first to explore the use of poly(butylene succinate-co-adipate) grafted with maleic anhydride (PBS-g-MAH) as a novel reactive additive to compatibilize PHBV/PBSA blends. The compatibilizer was prepared by a reactive melt-mixing process of PBSA and maleic anhydride (MAH) using dicumyl peroxide (DCP) as an organic radical initiator, achieving a grafting degree (Gd) of 5.4%. Biopolyester blend films were thereafter prepared via cast extrusion and their morphological, thermal, mechanical, and barrier properties were characterized. Compatibilization by PBSA-g-MAH was confirmed by observing an improved phase interaction and lower dispersed domain sizes in the blends with 15 wt% PBSA. These compatibilized PHBV/PBSA blends were thermally stable up to 285 °C, showed enhanced ductility and toughness, as well as providing an improved barrier against water and limonene vapors and oxygen. These findings suggest that the use of MAH-grafted biopolyesters can represent an effective strategy to improve the properties of biopolyester blends and open up new opportunities for the application of PHBV-based formulations for food packaging.

Impact of Hot-Melt Extrusion on Glibenclamide's Physical and Chemical States and Dissolution Behavior: Case Studies with Three Polymer Blend Matrices.

This research work dives into the complexity of hot-melt extrusion (HME) and its influence on drug stability, focusing on solid dispersions containing 30% of glibenclamide and three 50:50 polymer blends. The polymers used in the study are Ethocel Standard 10 Premium, Kollidon SR and Affinisol HPMC HME 4M. Glibenclamide solid dispersions are characterized using thermal analyses (thermogravimetric analysis (TGA) and differential scanning calorimetry), X-ray diffraction and scanning electron microscopy. This study reveals the transformation of glibenclamide into impurity A during the HME process using mass spectrometry and TGA. Thus, it enables the quantification of the extent of degradation. Furthermore, this work shows how polymer-polymer blend matrices exert an impact on process parameters, the active pharmaceutical ingredient's physical state, and drug release behavior. In vitro dissolution studies show that the polymeric matrices investigated provide extended drug release (over 24 h), mainly dictated by the polymer's chemical nature. This paper highlights how glibenclamide is degraded during HME and how polymer selection crucially affects the sustained release dynamics.

Evaluation and optimization of esterified starch and Canna edulis ker fiber films for food packaging applications

Starch-based films reinforced with Canna edulis Ker fiber were developed by a reactive extrusion process in which an esterification reaction was generated using maleic anhydride as a modifying agent and glycerin as a plasticizer. A Box-Behnken experimental design and the response surface methodology allowed modeling of the mechanical and physicochemical properties and their subsequent optimization to obtain flexible or rigid materials with different approaches in food packaging. The optimal composition for the rigid and flexible material was 10 and 2 % (w/w) lignocellulosic fibers, 30 and 30 % (w/w) glycerol, and 4 and 4 % (w/w) maleic anhydride, respectively. Glycerol and maleic anhydride were the key variables that influenced the water solubility and water absorption of the materials. The values of the rigid and flexible material properties of elastic modulus, tensile strength, elongation at break, water solubility, and water absorption were 2.58 and 1.51 GPa, 112.04 and 104.56 Mpa, 6.58 and 10.44 %, 21.63 and 21.85 %, and 139.72 and 141.06, respectively.

Parameter Optimization in FDM Filament Fabrication via Single Screw Extruder

The presence of polymer material filaments plays a crucial role in the realm of 3D printing. These filaments are utilized in 3D printing to create prototype products efficiently and cost-effectively. However, ensuring the production of high-quality prototype products necessitates the use of superior filaments characterized by consistent diameter and a round cross-section. Filaments are typically manufactured through an extrusion process using either a single screw extruder or a twin extruder. In this research, a DIY single-screw extruder was developed specifically for filament production. The main objective of this study is to generate quality filaments by optimizing the extruder parameters for various polymer materials. Three different polymers; Ethylene-vinyl Acetate (EVA), Polypropylene (PP), and Acrylonitrile Butadiene Styrene (ABS) were employed in this study. The research aimed to assess the melt flow index (MFI) to demonstrate viscous behavior and establish the ideal parameters for each material in the extrusion process. A total of 27 EVA material filament samples, 26 PP filament samples, and 26 ABS filament samples were successfully produced. Through analysis, optimal settings were identified for EVA, PP, and ABS filaments, resulting in high-quality production. The recommended parameters for producing quality EVA filaments included a temperature of 160°C, screw speed of 400 rpm, and take-up speed of 400 rpm. For PP filaments, the optimal settings comprised a temperature of 230°C, screw speed of 700 rpm, and take-up speed of 250 rpm. Lastly, ABS filament production was optimized with a temperature of 210°C, screw speed of 300 rpm, and take-up speed of 100 rpm. This project's outcomes are anticipated to have significant implications for future advancements in filament manufacturing processes.

Preparation, Characterization and Evaluation of Nintedanib Amorphous Solid Dispersions with Enhanced Oral Bioavailability.

The dissolution and bioavailability challenges posed by poorly water-soluble drugs continue to drive innovation in pharmaceutical formulation design. Nintedanib (NDNB) is a typical BCS class II drug that has been utilized to treat idiopathic pulmonary fibrosis (IPF). Due to the low solubility, its oral bioavailability is relatively low, limiting its therapeutical effectiveness. It is crucial to enhance the dissolution and the oral bioavailability of NDNB. In this study, we focused on the preparation of amorphous solid dispersions (ASD) using hot melt extrusion (HME). The formulation employed Kollidon® VA64 (VA64) as the polymer matrix, blended with the NDNB at a ratio of 9:1. HME was conducted at temperatures ranging from 80°C to 220°C. The successful preparation of ASD was confirmed through various tests including polarized light microscopy (PLM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). The in-vitro cumulative release of NDNB-ASD in 2h in a pH 6.8 medium was 8.3-fold higher than that of NDNB (p < 0.0001). In a pH 7.4 medium, it was 10 times higher (p < 0.0001). In the in-vivo pharmacokinetic experiments, the area under curve (AUC) of NDNB-ASD was 5.3-fold higher than that of NDNB and 2.2 times higher thanthat of commercially available soft capsules (Ofev®) (p < 0.0001). There was no recrystallization after 6months under accelarated storage test. Our study indicated that NDNB-ASD can enhance the absorption of NDNB, thus providing a promising method to improve NDNB bioavailability in oral dosages.