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The crystallization of Mefenamic Acid, (MA), which has a prevalent usage in drug formulation, was investigated. MA is a high-dose, anti-inflammatory, analgesic agent used for pain in menstrual disorders. Some negative properties of MA are a high hydrophobicity and propensity to stick to surfaces, which cause great problems during granulation and tabletting. To facilitate tabletability, enhance dissolution rates, and develop a stable and reproducible dosage form, investigation of the physicochemical properties of mefenamic acid is necessary. Pharmaceutical drugs are commonly crystalline materials and are therefore subject to polymorphism. Polymorphism, the ability of a substance to exist in more than one crystalline form, is a significant phenomenon in the field of chemical engineering sciences, including pharmaceutical development. Establishing the polymorphic behaviour of a drug molecule early in development minimizes the number of unsuitable candidates developed and reduces the risk of encountering issues later which may have a major financial and time impact. Mefenamic acid crystals were recrystallized from five different solvents of N, Ndimethylformamide (DMF), acetone, N, N-dimethylacetamide (DMA), Dimethylsulfoxide (DMS) and Ethyl Acetate (EA). In order to characterize the Mefenamic Acid crystal structure and the polymorphic forms of the crystals obtained by recrystallization, the scanning electron microscopy (SEM), Raman diffractometry and Xray pattern were used. From the industrial crystallization point of view, the crystal size distribution (CSD), the crystal shape, the polymorphic form and the crystallization steps are important factors that affect the quality and bioavailability of a drug. For the determination of crystal size distribution of MA, The Focused Beam Reflectance Measurement (FBRM) technique was practiced and CSD profiles were obtained.

Biodegradable and antimicrobial polymeric food packaging materials are very important because of environmental problems, for quality, and the shelf life of the product. The aim of this paper is to produce antimicrobial and biodegradable food packaging films with polycaprolactone (PCL). Using the amount of PCL (w/w) as the basis and to control the degradation time and to give antimicrobial properties, 0.4 wt% of organo nano clay (C) and 25, 50, and 75 wt% chitosan (K), and the use of glycerol monooleate (GMO) or oleic acid (OA) as a plastifier (5, 10, 20, and 30 wt%) are added and 12 polymeric composite films were prepared. The samples were coded as PCL (P), organo nanoclay (C), oleic acid (O), and glycerol monooleate (G). For example, P_C0.4_G5 refers to the PCL composite film containing 0.4 wt% clay and 5 wt% glycerol monooleate (G). The disc diffusion procedure with Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, and Candida albicans test microorganisms were used to evaluate the antimicrobial properties of the films. PCL_C0.4_O5, PCL_C0.4_G5, PCL_C0.4_G10_K25, PCL_C0.4_O10_K25, and PCL_C0.4_O20_K50 and neat chitosan films have antimicrobial properties. A small amount of organo nano clay, 0.4 wt%, has an antimicrobial effect on C. albicans. The PCL_C0.4_G10_K25 composite film has an antimicrobial effect on E. coli, P. aeruginosa, and C. albicans. Mechanical tests were performed, and it was observed that the mechanical properties of PCL composite films decrease with the addition of chitosan. J. VINYL ADDIT. TECHNOL., 24:376–387, 2018. © 2017 Society of Plastics Engineers

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The isothermal crystallization and mechanical behavior of biodegradable polycaprolactone (PCL) composites with organic (oleic acid and glycerol monooleate) and inorganic (zinc oxide, organoclay, and hydroxy apatite) additives used alone or simultaneously were investigated. The effect of all additives on the degree of crystallinity percentage (DOC%), isothermal crystallization kinetics parameters, and mechanical test results of PCL composites was studied. The PCL composite films were prepared by solvent casting by using dichloromethane as the solvent. The films were characterized by X-ray diffraction, differential scanning calorimetry (DSC), and tensile tests. DSC of the first melting and X-ray diffraction DOC% results (for composites by solvent casting) are compatible. The values by DSC of the second melting (for composites by extrusion method) are lower. Organoclay gives the highest crystallinity among the other inorganic additives used. Small amounts of inorganic additives act as a nucleating agent and increase the crystallinity; the higher amounts decrease. The organic additives act as the plasticizer. When used alone, it lowers the crystallinity, but when used with inorganic additives, it improves the dispersion of inorganic particles in the polymer matrix. The isothermal crystallization kinetics parameters by Avrami analysis showed that crystallization was controlled by nucleation and the crystals had spherical structure. The nucleation type changed between thermal and athermal nucleation. The Pukanzky model interaction parameter B indicated that the organic additives improved the dispersion of inorganic particles in the polymer matrix. Statistically significant, eight correlations (F > 6) were obtained for the crystallinity, crystallization parameters, Young's modulus, and tensile strength as a function of concentration of additives. J. VINYL ADDIT. TECHNOL., 21:174-182, 2015.

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The isothermal crystallization and mechanical behavior of polycaprolactone (PCL) with zinc oxide (ZnO) with oleic acid and glycerol monooleate (GMO) were studied. Theoretical melting points calculated by the Flory-Huggins and Thompson-Gibbs models were thoroughly compared with differential scanning calorimetry experimental observations. The isothermal crystallization kinetic parameters by Avrami analysis showed that crystallization was controlled by nucleation, crystal growth was spherical, and the nucleation type changed between thermal and athermal nucleation. X-ray diffraction showed that when the additives were used together both the crystal thickness and the degree of crystallinity increased. A multiple-response regression analysis was made with the ZnO, oleic acid, and GMO concentrations as variables and the crystallinity as output. Interaction parameters by the Pukanzky model were calculated from the tensile strength at the yield point and indicated that the addition of oleic acid or GMO improved the interface between the ZnO particles and PCL.

In this study, scaffolds with polycaprolactone (PCL) and hydroxy apatite (HA) were produced. Their properties are not sufficient to be used alone. Oleic Acid (OA) and glycerol monooleate (GMO) as organic additives were selected for a homogeneous distribution of the ceramic material in the polymer matrix. Biocomposite materials were prepared with solvent casting-salt leaching technique using dichloromethane as the solvent. Salt was used as the porosifier. Materials were kept in simulated body fluid (SBF) to determine the bioactivity in vitro conditions. FTIR and EDX analyses for chemical characterization, tensile and compressive tests for mechanical properties, SEM analyses for surface properties and BET analyses for pore sizes, total surface areas and total pore volumes of scaffolds were performed. FTIR, EDX, and SEM analyses were repeated after SBF treatment. Pore diameters were highly increased with 3 and 20 wt% HA addition. Small amount of GMO addition is more effective on pore size. Mechanical properties of scaffolds were suitable for soft tissue applications, as smooth muscle cells, skin and cancellous bone. The cytotoxicity and cell proliferation on scaffolds were studied with smooth muscle cells (SMC) and L929 fibroblastic cells in vitro. No cytotoxic effect was observed for the scaffolds in both cell types. J. VINYL ADDIT. TECHNOL., 00:000-000, 2016.