Lowest Degree Of Crystallinity Research Articles

Nanosilica/recycled polycarbonate composites for electronic packaging

Several simple methods were performed to recycle compact discs (CDs) using an alkaline solution. The hydrophilic silica nanoparticles were incorporated into the recycled deinked polycarbonate CDs, and these particles affected the dielectric, structure, and thermal properties of the recycled polycarbonates. The thermal properties of recycled CDs were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). No significant change in the thermal stability of polycarbonate/silica nanocomposites was observed with the mechanical /chemical modifications. X-ray diffraction (XRD) revealed the structural aspects, showing a correlation between crystallinity, silica nanoparticles, and modification methods. The mechanically treated sample after chemical handling had the lowest degree of crystallinity (48%), showing that the modification methods enhanced the formation of the amorphous state, thus affecting its dielectric properties. Scanning electron microscopy (SEM) characterized the CD samples' microstructure and morphology. Finally, the dielectric properties were studied using broadband dielectric spectroscopy (BDS) in the 101 - 106 Hz range. The samples prepared using chemical and mechanical treatments were of low dielectric loss. This increases its importance when such samples are used as antistatic charge materials. For these reasons, recycled PC/SiO2 nanocomposites are recommended as effective packaging materials for electronic components.

Steps towards the ideal CV and GCD results with biodegradable polymer electrolytes: Plasticized MC based green electrolyte for EDLC application

Advanced materials are a primary focus of many research groups for applications in energy storage devices. Natural polymers, as a branch of advanced materials, are currently a hot topic to produce clean energy and reduce microplastics problems in the ocean and their potential harm to human health through ingestion. A novel biodegradable green polymer electrolyte was selected for energy storage in the current investigation. The MC polymer was impregnated with a fixed weight percent (40 %) of sodium thiocyanate (NaSCN) and different amount of glycerol to produce flexible films of solid polymer electrolytes (SPEs) using solution casting method. The XRD test reveals that the lowest degree of crystallinity is present in the most conductive electrolyte with increasing plasticizer. According to the electrochemical impedance spectroscopy (EIS) results, the sample that was incorporated with 50 % glycerol displayed the highest conductivity. FTIR was employed to observe the interaction of electrolyte components. Ions were found to be the primary species contributing to conduction, with transference numbers of 0.958 and 0.042 for ions (tion) and electrons (te), respectively. The results obtained from the linear sweep voltammetry (LSV) data confirm that the sample can withstand a voltage of approximately 2.54 V. This voltage level is suitable for extensive practical applications. The shape of the CV pattern was almost comparable to an ideal rectangular shape at low scan rates. A slight increase in the internal resistance (ESR) of the EDLC cell was observed, which increased from 59 to 68 Ω. The battery cycler was used to charge and discharge the designed EDLC device and some key parameters, including capacitance (110 F.g−1), energy density (15 Wh.Kg−1), and power density (1300 W.Kg−1) were determined from the discharge curve. Ultimately, based on the study of the assembled cell, it has been suggested that supercapacitors have emerged as potential alternative to replace environmentally harmful Li-ion batteries in advancing green energy.

Effect of ionic liquids on the performance of dye-sensitized solar cells using poly(vinyl alcohol)/ polypyrrole based polymer electrolytes

ABSTRACT A novel quasi-solid-state polymer electrolyte was prepared using poly(vinyl alcohol)-polypyrrole, potassium iodide, iodine, and ethylene carbonate mixed with two types of ionic liquids, 1-methyl-3-propylimidazolium iodide (MPII) and 1-ethyl-3-methylimidazolium iodide (EMII). The prepared polymer electrolyte was structurally characterized by FTIR spectroscopy. The lowest degree of crystallinity and activation energy were found in the MPII-incorporated polymer electrolytes. Higher values of dislocation density and microstrain are obtained for ionic liquid-incorporated polymer electrolytes. The lowest value of series resistance was observed in MPII-based polymer electrolyte and thereby the conduction was increased. The average roughness of the MPII-based polymer electrolyte at 17.901 nm was strongly dependent on the influence of the MPII content. The dye-sensitized solar cells (DSSC) built with MPII-based polymer electrolytes have achieved the highest photo-conversion efficiency of 4.51% under 100mWcm−2 illumination.

Electrodeposition of Hydroxyapatite Coating on Ti6Al4V Alloy: Mechanistic Investigation of the Substrate Crystallographic Texture Effect

Hydroxyapatite (HAp) coating electrodeposition was performed on three orthogonal surfaces of duplex-annealed Ti6Al4V alloy. This approach made it possible to investigate the effect of substrate crystallographic texture on hydroxyapatite coating properties exclusively from its microstructure. The coating characteristics were evaluated by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), laser surface profilometry, and potentiodynamic polarization test. The results showed that the presence of low-surface energy planes leads to smaller HAp deposits of 39 ± 4 μm due to the higher nucleation rate during electrodeposition. The highest surface roughness value of 75 ± 1 μm, as well as the lowest degree of crystallinity, equal to 23.5%, belonged to the surface in which and planes of high-surface energy placed in parallel to the surface. The electrochemical test results showed that the protective efficiency of HAp coatings was the highest for the surface with planes in parallel. This was attributed to the increased thickness and the low porosity content of the coating.

The Modulus of the Amorphous Phase of Semicrystalline Polymers

A universal method for determining the modulus of the interlamellar amorphous phase of semicrystalline polymers was proposed. The basics of the method were presented on the example of high-density polyethylene (HDPE). The local deformation of the amorphous component was induced by the introduction of a swelling agent (hexane). The swelling-induced local strain and local stress of the interlamellar amorphous phase were estimated based on the changes of the long period and the yield stress, respectively. The determined modulus of the interlamellar amorphous phase of HDPE (≈40 MPa) was an order of magnitude higher than the modulus of the bulk rubbery amorphous phase of HDPE (≈3 MPa). The modulus of the interlamellar amorphous phase of other semicrystalline polymers, such as polypropylene (PP), low-density polyethylene (LDPE), and an ethylene–octane copolymer (EOC), was also determined and amounted to 50.3, 11.8, and 4.2 MPa, respectively. For polyethylene materials (HDPE, LDPE, and the EOC), a linear increase in the modulus of the interlamellar amorphous phase with increasing of the degree of crystallinity was observed. This effect was correlated with a decrease in “deformability” of the amorphous layers (a decrease in the swelling-induced local strain of amorphous layers for samples with higher crystallinity). The decrease in “deformability” of the amorphous component at low strains was probably caused by an increase in the density of stress transmitters (entanglements and tie molecules), which affected the mechanical properties (modulus) of the interlamellar regions. In the case of the material with the lowest degree of crystallinity (EOC, 26.2 vol%), the modulus of the interlamellar amorphous phase was similar to the modulus of the bulk rubbery amorphous phase, which indicated a very limited influence of the lamellar crystals on the stiffness of the amorphous regions.

Conduction Mechanism of Chitosan/Methylcellulose/1-Butyl-3 Methyl Imidazolium Bis (Trifluoromethylsulfonyl) Imide (BMIMTFSI) Biopolymer Electrolyte Doped with Ammonium Triflate

Chitosan/methylcellulose/1-butyl-3 methyl imidazolium bis (trifluoromethylsulfonyl) imide (BMIMTFSI) biopolymer electrolyte has been prepared via solution casting technique by doping with different weight percentages of ammonium triflate (NH4CF3SO3) salt. The films were characterized by impedance spectroscopy to measure the ionic conductivity. Samples with 25 wt.% of NH4CF3SO3 exhibited the highest conductivity of 7.64 × 10-4 S cm-1 at ambient. Dielectric data showed that the increase in conductivity could be due to the increase in the number of charge carriers, while modulus study confirmed the non-Debye behaviour. Temperature dependence study showed that the polymer electrolyte system obeyed the Arrhenius rule. Conduction mechanism analysis showed that this system matched the Quantum Mechanical Tunnelling (QMT) behaviour. X-ray Diffraction (XRD) spectra, which had been deconvoluted using Origin 8 software disclosed that samples with the lowest degree of crystallinity (Xc %) obtained the highest ionic conductivity. On the other hand, Fourier Transform Infrared (FTIR) spectra, which were also deconvoluted using the same software showed that samples with the highest ionic conductivity had the highest number of mobile ions in this system.

Structural, ion transport parameter and electrochemical properties of plasticized polymer composite electrolyte based on PVA: A novel approach to fabricate high performance EDLC devices

In this study a novel polymer composite electrolytes (PCEs) based on poly (vinyl alcohol) (PVA): Ce(III)-complex:NH4SCN plasticized with glycerol are prepared by solution cast technique. XRD and FTIR routes are used to study the film structure. The crystalline and amorphous areas are determined through the deconvolution of XRD spectra and their values were used to calculate the degree of crystallinity. The deconvolutions of the FTIR of asymmetric C≡N stretching mode are carried out to establish the bands coupled with free ions, contact ion pairs and ion aggregates. The maximum ambient temperature DC conductivity of 2.07 × 10−3S cm−1 is recorded for the sample with the lowest degree of crystallinity. It was found that the number density (n), mobility (μ) and diffusion coefficient (D) of ions are increased with the glycerol concentration. Field emission scanning electron microscopy (FESEM) is used to examine the effect of plasticizer on film morphology. The DC conductivity trend is interpreted in detail with the help of dielectric properties. It is found that the transference numbers of ions (tion) and electrons (tel) are 0.965 and 0.035, respectively. It is shown by the linear sweep voltammetry (LSV) that the potential window of the PCE is 2.1 V. A shape, which is nearly rectangular at lower scan rates, is identified from cyclic voltammetry (CV). Specific capacitance and energy density are exhibited by EDLC with average of 161.5 F/g and 18.17 Wh/kg, respectively within 400 cycles. The initial power density is shown by EDLC to be 2.825 × 103 W/kg.

Ion conduction in chitosan-starch blend based polymer electrolyte with ammonium thiocyanate as charge provider

The global issue of environmental pollution has become the motivation for researchers to develop natural based products. Researchers start to substitute synthetic polymers with natural polymers as host and ammonium salts instead of lithium salts for electrolyte application due to biodegradable, safer to handle and low in cost. In this work, a green polymer electrolyte system is prepared by blending 80 wt.% starch and 20 wt.% chitosan with ammonium thiocyanate (NH4SCN) as dopant salt. The highest room temperature conductivity of (1.30 ± 0.34) × 10−4 S cm−1 is obtained when the starch–chitosan blend is doped with 30 wt.% NH4SCN electrolyte which is found to obey Arrhenius rule. The deconvolution of Fourier transform infrared (FTIR) analysis has proved the molecular interaction between starch, chitosan and NH4SCN. The number density (n), mobility (μ) and diffusion coefficient (D) of ions are found to be affected by NH4SCN concentration. This result is further supported by the XRD sample with 30 wt.% NH4SCN which exhibited the most amorphous structure with the lowest degree of crystallinity. Conduction mechanism for the highest conducting electrolyte follows correlated barrier hopping (CBH) model.

Unmasking the heterogeneity of carbohydrates in heartwood, sapwood, and bark of Eucalyptus

In this study, the cellulose and hemicelluloses in heartwood, sapwood, and bark of E. urophylla × E. grandis were comprehensively investigated. The ultrastructural topochemistry of carbohydrates in cell walls was examined in situ by confocal Raman microscopy. Cellulose and alkali-extractable hemicelluloses samples were isolated from different tissues and comparatively characterized by compositional carbohydrate analyses, determination of molecular weights, FT-IR spectroscopy, and XRD and NMR techniques. It was found that among all of the samples, heartwood cellulose had the highest molecular weight as well as the lowest degree of crystallinity. Meanwhile the hemicelluloses in heartwood had higher xylose content, lower degree of branching, slightly lower molecular weights but narrower polydispersity than those in sapwood. The eucalyptus hemicelluloses mainly consisted of (1→4)-β-D-xylan backbone with glucuronic acid side chains. Furthermore, the hemicelluloses isolated from sapwood had a higher degree of substitution with terminal galactose than those isolated from heartwood and bark.

Structural and ionic conductivity characterization of PEO:MC-NH4I proton-conducting polymer blend electrolytes based films

In the present work, series of proton-conducting polymer electrolyte films based on polyethylene oxide/methylcellulose complexed with different concentrations of ammonium iodide (NH4I) as doping salt were prepared by solution cast technique. The produced films were characterized by X-ray diffraction (XRD), Polarized optical microscope (POM), Fourier transform infrared (FTIR), and electrical impedance spectroscopy (EIS). The XRD and POM results reveal that the sample with 30 wt% NH4I (PBE-30) has the lowest degree of crystallinity. The observed shift in the IR peak position of the N–H stretching band at regions 3000–3300 cm−1 as a function of NH4I concentration suggested clear evidence of an interaction between host polymers and NH4I. The highest value of electrical conductivity was found to be 7.62×10-5S.cm-1 at 303K for PBE-30. The temperature-dependent of electrical conductivity and ion transport properties was described using both the Arrhenius and Vogel-Tammann-Fulcher (VTF) relations. The activation energy values decrease with increasing DC conductivity and vice-versa.

Preparation and Composition Optimization of PEO:MC Polymer Blend Films to Enhance Electrical Conductivity.

The polymer blend technique was used to improve amorphous phases of a semicrystalline polymer. A series of solid polymer blend films based on polyethylene oxide (PEO) and methylcellulose (MC) were prepared using the solution cast technique. X-ray diffraction (XRD), Polarized optical microscope (POM), Fourier transform infrared (FTIR) and electrical impedance spectroscopy (EIS) were used to characterize the prepared blend films. The XRD and POM studies indicated that all polymer blend films are semicrystalline in nature, and the lowest degree of crystallinity was obtained for PEO:MC polymer blend film with a weight ratio of 60:40. The FTIR spectroscopy was used to identify the chemical structure of samples and examine the interactions between chains of the two polymers. The interaction between PEO and MC is evidenced from the shift of infrared absorption bands. The DC conductivity of the films at different temperatures revealed that the highest conductivity 6.55 × 10−9 S/cm at ambient temperature was achieved for the blend sample with the lowest degree of crystallinity and reach to 26.67 × 10−6 S/cm at 373 K. The conductivity relaxation process and the charge transport through the hopping mechanism have been explained by electric modulus analysis. The imaginary part of electrical modulus M″ shows an asymmetrical peak, suggesting a temperature-dependent non-Debye relaxation for the PEO:MC polymer blend system.

Immunomodulatory Properties of Composite Materials Based on Polylactide and Hydroxyapatite

In the present study composites based on polylactide and hydroxyapatite with the content of components 50:50 and 75:25 were investigated. Components were mixed at 40°C, which was followed by the sonication procedures and its precipitation in ethanol. The analysis of the following composite materials revealed that their chemicalcrystallographic characteristics of individual components remained intact after varying its dispersion and material crystallinity degree. Composite material of the ratio 75:25 were characterized by the lowest degree of crystallinity - 20.5% and the average crystallite size up to 28.8 nm showed an increased roughness and dispersive component of surface energy. In comparison to polylactide, the composite has a high capacity for osseointegration. In the paper, special attention is given to the immunomodulatory properties of composite materials. Assessment of the immune system cells showed that the macrophages are most viable in the presence of pure polylactide and composite 75/25. Intensive secretion of proinflammatory cytokines in macrophage cultures in vitro was not found at that.

Green electrolytes based on dextran-chitosan blend and the effect of NH4SCN as proton provider on the electrical response studies

Dextran-chitosan blend added with ammonium thiocyanate (NH4SCN)-based solid polymer electrolytes are prepared by solution cast method. The interaction between the components of the electrolyte is verified by Fourier transform infrared (FTIR) analysis. The blend of 40 wt% dextran-60 wt% chitosan is found to be the most amorphous ratio. The room temperature conductivity of undoped 40 wt% dextran-60 wt% chitosan blend film is identified to be (3.84 ± 0.97) × 10−10 S cm−1. The inclusion of 40 wt.% NH4SCN to the polymer blend has optimized the room temperature conductivity up (1.28 ± 0.43) × 10−4 S cm−1. Result from X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis shows that the electrolyte with the highest conductivity value has the lowest degree of crystallinity (χ c) and the glass transition temperature (T g), respectively. Temperature-dependence of conductivity follows Arrhenius theory. From transport analysis, the conductivity is noticed to be influenced by the mobility (μ) and number density (n) of ions. Conductivity trend is further verified by field emission scanning electron microscopy (FESEM) and dielectric results.

Enhanced enzymatic degradation in nanocomposites of various organically-modified layered zinc phenylphosphonates and poly (butylene succinate-co-adipate)

In this work, two long-chain alkylamines, dodecylamine (DDA) and octadecylamine (ODA), intercalated with layered zinc phenylphosphonates (PPZns) were prepared using a simple chemical intercalation method. Both biocompatible poly(butylene succinate-co-adipate) (PBSA)/organically-modified PPZn nanocomposites fabricated by a melt-mixing technique have been characterized by wide-angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM). These results indicated that the stacking layers of the ODA-PPZn in the PBSA matrix were fully/partially exfoliated and the intercalated PBSA/DDA-PPZn nanocomposites were formed. Enzymatic degradation tests using Lipase from Pseudomonas sp. as the enzyme was investigated. The weight loss of PBSA increases with an increase in the content of organically-modified PPZn. The degradation rate of all samples varied in the order PBSA/ODA-PPZn nanocomposites > PBSA/DDA-PPZn nanocomposites > neat PBSA. This result is probably due to the lowest degree of crystallinity for PBSA/ODA-PPZn nanocomposites. The degradation behavior of the neat PBSA belongs to exo-type hydrolysis activity due to the degradation starts from both ends of the polymer chains.

Effect of spray-drying temperature on the formation of flower-like lactose for griseofulvin loading

The effect of spray-drying temperature has been studied for the first time on the formation of flower-like lactose for drug loading in this work. The synthesis of the flower-like lactose involves two steps, namely spray drying and ethanol washing. Four inlet temperatures (140°C, 150°C, 160°C and 200°C) have been used in the spray-drying step. The effect of the spray-drying temperature was significant on the formation of flower-like lactose, in terms of crystallinity, porosity and drug loading capacity. Higher inlet temperatures are more likely to produce lactose in the β form. The engineered flower-like lactose is highly porous, with pores of 1.4, 3.4 and 29.3nm (diameter). Compared with other inlet temperatures, the flower-like lactose dried at 150°C has the lowest degree of crystallinity, the largest pore surface area (38±4m2/g) and pore volume (0.65±0.09cm3/g), and the highest griseofulvin loading capacity (16.2±0.3%, w/w). A griseofulvin dissolution test has suggested that the flower-like lactose can be used as a drug carrier to enhance drug solubility.

NH4NO3 as charge carrier contributor in glycerolized potato starch-methyl cellulose blend-based polymer electrolyte and the application in electrochemical double-layer capacitor

Potato starch (PS)-methyl cellulose (MC) blend solid biopolymer electrolytes infused with ammonium nitrate (NH4NO3) and glycerol as plasticizer are made via the solution cast technique. Fourier transform infrared (FTIR) spectroscopy indicates that NH4NO3 has interacted with the polymer blend host. The addition of 40 wt% glycerol in the highest conducting plasticizer free electrolyte has improved the conductivity to the order of ∼10−3 S cm−1. The thermal stability of the electrolytes is identified by thermogravimetric analysis (TGA). Result from X-ray diffraction (XRD) analysis shows that the electrolyte with maximum conductivity value has the lowest degree of crystallinity. Differential scanning calorimetry (DSC) analysis reveals that the highest conducting plasticized electrolyte possesses the lowest glass transition temperature (T g) of −27.5 °C. Conductivity trend is further verified by dielectric analysis. Transference numbers of ion (t ion) and electron (t e) for the highest conducting electrolyte are identified to be 0.98 and 0.02, respectively, confirming that ions are the dominant charge carriers. Linear sweep voltammetry (LSV) evaluates that the potential window for the electrolyte is 1.88 V. The internal resistance of the electrochemical double-layer capacitor (EDLC) is between 29 and 64 Ω. From the charged-discharged measurement, the value of C s is 31 F g−1. The EDLC is stable over 1000 cycles.

Development of polyacrylonitrile-based polymer electrolytes incorporated with lithium bis(trifluoromethane)sulfonimide for application in electrochromic device

In this study, polyacrylonitrile (PAN) as a polymer host is added with varying contents of lithium bis(trifluoromethane)sulfonimide (LiTFSI) as source of lithium (Li+) ions to form polymer electrolyte (PE) films. Dimethylformamide (DMF) is employed as the solvent. The electrical and structural properties of the PAN-based electrolytes are investigated by electrochemical impedance spectroscopy (EIS), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). The PE film containing 40wt. % of LiTFSI is found to exhibit the best ambient conductivity of 2.54×10−4Scm−1 and the lowest degree of crystallinity. Investigation by FTIR spectroscopy has shown that PAN⋯DMF and DMF⋯Li+ interactions have occurred in the PAN-DMF-LiTFSI complexes. From XRD analysis, the films are found to be more amorphous with increasing LiTFSI contents. An electrochromic device is fabricated in the configuration of glass|ITO|WO3|electrolyte|CeO2-TiO2|ITO|glass, and the cathodic coloration and anodic bleaching of WO3 are found to occur at around −1.25V and −0.40V, respectively.

Effect of amylose, particle size & morphology on the functionality of starches of traditional rice cultivars

The research was carried out to investigate the effect of starch powder particle size, morphology, amylose content and varietal effect on physicochemical, X-ray diffraction pattern, thermal and pasting characteristics. The results indicated that starches isolated from seven traditional rice cultivars of temperate region of India have possessed higher yield (82.47–86.83%) with lower degree of granule damage and higher level of starch crystallinity (36.55–39.15%). The water and oil binding capacities were observed to correlate positively with amylose content. The bulk density and color parameters of starches were found to have linked with starch powder particle size coupled with arrangement and morphology of the starch granules. The rice cultivars having smaller starch powder particle size indicated lowest degree of crystallinity. Morphological studies revealed that the starches with tightly packed granules had greater mean granular width, while granules with openly spaced granular morphology depicted the higher values for mean granular length. The peak height index (PHI) among different starches ranged from 1.01 to 2.57 whereas the gelatinization range varied from 10.66 to 10.88. Concluding, the differences in distributional pattern of starch granule size and shape and powder particle size indicated a significant effect on the functional properties of starch.

The control and optimization of the curing process of epoxy coatings: a case of poly(glycidoxy siloxane) resins

AbstractCoatings from poly(glycidoxy siloxane) resins were developed and their mechanical properties examined. Three different resins with varying numbers of methyl siloxane and glycidyl siloxane units were tested. Crystallinity was found to be a very important indicator of the mechanical properties of coatings, as the parameters such as cupping and hardness were linearly dependent on the degree of crystallinity of coatings. The method involving the spectrophotometric determination of unbounded amine curing agent was successfully applied as a way of optimizing the curing process both for expected mechanical properties and for ecological aspect. It was found that the resin with 50 methyl siloxane and 25 glycidyl siloxane units was the most appropriate for technological use because of the preferred mechanical properties and stability of technological parameters. Interestingly, this type of resin was characterized by the lowest degree of crystallinity. The curing conditions leading to the optimal product corresponded to 30 min of curing at 120°C or 20 min at 140°C. Under such conditions, the amount of released unbounded amine was the lowest. It was also found that poly(glycidoxy) siloxane resins may be ecologically valuable since the release of amine from this type of resins is smaller than that from a typical epoxy resin.

Influence of the preparation method on the physicochemical properties of indomethacin and methyl-β-cyclodextrin complexes

The main objective of this study was to investigate different manufacturing processes claimed to promote inclusion complexation between indomethacin and cyclodextrins in order to enhance the apparent solubility and dissolution properties of indomethacin. Especially, the effectiveness of supercritical carbon dioxide processing for preparing solid drug–cyclodextrin inclusion complexes was investigated and compared to other preparation methods. The complexes were prepared by physical mixing, co-evaporation, freeze drying from aqueous solution, spray drying and supercritical carbon dioxide processing methods. The prepared complexes were then evaluated by scanning electron microscopy, differential scanning calorimetry, X-ray powder diffraction, solubility and dissolution studies. The method of preparation of the inclusion complexes was shown to influence the physicochemical properties of the formed complexes. Indomethacin exists in a highly crystalline solid form. Physical mixing of indomethacin and methyl-β-cyclodextrin appeared not to reduce the degree of crystallinity of the drug. The co-evaporated and freeze dried complexes had a lower degree of crystallinity than the physical mix; however the lowest degree of crystallinity was achieved in complexes prepared by spray drying and supercritical carbon dioxide processing methods. All systems based on methyl-β-cyclodextrin exhibited better dissolution properties than the drug alone. The greatest improvement in drug dissolution properties was obtained from complexes prepared using supercritical carbon dioxide processing, thereafter by spray drying, freeze drying, co-evaporation and finally by physical mixing.Supercritical carbon dioxide processing is well known as an energy efficient alternative to other pharmaceutical processes and may have application for the preparation of solid-state drug–cyclodextrin inclusion complexes. It is an effective and economic method that allows the formation of solid complexes with a high yield, without the use of organic solvents and problems associated with their residues.