Abstract The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out using Delphinium uncinatum and Erythrophyleum guineense plants extracts. The Au NPs obtained were characterized by various instrumental techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and UV/Visible (UV/VIS) spectrophotometer. The SEM study presented that E. guineense (GE) and D. uncinatum (GN) synthesized gold nanoparticles was below 100 and 300 nm, respectively. The micrographs also presented that E. guineense (GE) synthesized gold particles had irregular round shaped while the D. uncinatum (GN) synthesized nanoparticles had cylindrical shaped. The XRD spectra presented peaks at about 38.1°, 44.43°, 64.6° and 77.64° can be indexed to (111), (200), (220) and (311) orientation, respectively, which confirmed the presence of gold nanoparticles. It means that both E. guineense (GE) and D. uncinatum (GN) synthesized gold nanoparticles are highly crystalline. The UV/VIS analysis presented that both plant extracts significantly reduced the gold slat and as a result high quantity of gold nanoparticles were formed. The E. guanense gold NP and D. uncinatum gold NPs were investigated for their in-vitro cholinesterases inhibitory potentials in 62.5 -1000 µg/mL concentrations range. The bioactivity results presented that the loading of the test samples in gold NPs enhanced their AChE and BChE inhibitory potentials.

Resumen La síntesis verde de nanopartículas de oro (NP de Au) se llevó a cabo mediante extractos de plantas de Delphinium uncinatum y Erythrophyleum guineense. Las NP de Au obtenidas se caracterizaron mediante diversas técnicas instrumentales como microscopía electrónica de barrido (SEM), dispersión de energía de rayos X (EDX), difracción de rayos X (XRD) y espectrofotómetro UV / Visible (UV / Vis). El estudio SEM reveló tamaños de las nanopartículas de oro sintetizadas por E. guineense (GE) y D. uncinatum (GN) por debajo de 100 y 300 nm, respectivamente. Las micrografías también mostraron que las partículas de oro sintetizadas por E. guineense (GE) tenían una forma redonda irregular, mientras que las nanopartículas sintetizadas por D. uncinatum (GN) tenían una forma cilíndrica. Los patrones XRD presentaron picos a aproximadamente 38.1 °, 44.43 °, 64.6 ° y 77.64 ° pueden indexarse a la orientación (111), (200), (220) y (311), respectivamente, lo que confirmó la presencia de nanopartículas de oro cristalinas. El análisis UV / Vis mostró que ambos extractos de plantas formaron nanopartículas de oro. Se investigaron las NP de oro como inhibidores de colinesterasas in vitro en un intervalo de concentraciones de 62.5 a 1000 µg / ml. Los resultados de la bioactividad mostraron que la carga de las muestras de prueba en NP de oro mejoró sus potenciales inhibidores de AChE y BChE.

ABSTRACT The SWNTs was purified/functionalized by acid treatment method and the F-SWNTs were used as reinforcing materials. The acid treatment introduced carboxyl (–COOH) group to the SWNTs. The PVC and F-SWNTs/PVC films were prepared by solution casting method. The fractured surfaces of sample was analyzed through SEM and showed the dispersion of F-SWNTs in PVC. The thermal study indicated that the thermal stability of PVC is enhanced with F-SWNTs incorporation. The mechanical properties were also increased with CNTs filling. The solvent uptake study suggested that the nanocomposites resist towards solvent uptake, which is due to the hydrophobic nature of CNTs and their irregular network formation within the polymer matrix.

Kaolin clay/poly (butylene terephthalate) (clay/PBT) composites films were prepared by solution casting technique. The scanning electron microscope (SEM) study showed that clay particles were well dispersed and embedded within the PBT matrix. The TGA thermograms showed that the thermal stability of PBT matrix was slightly improved by the incorporation of clay into the polymer matrix. The polarized optical microscopy (POM) study presented that the size of spherulites of PBT was decreased by the incorporation of clay into matrix, which might be due to nucleation effect of kaolin clay. The tensile strength and modulii of PBT polymer matrix were also significantly improved by the addition of clay polymer matrix. The solvent uptake study showed that the uptake of various solvents by clay/PBT nanocomposite were lower than neat PBT.

Poly (methyl methacrylate) (PMMA)/Poly ethylene oxide (PEO) (15 wt.% PMMA/85 wt.% PEO (PMMA/PEO-A) and 30 wt.% PMMA/70 wt.% PEO (PMMA/PEO-B)) blends, and functionalized multiwalled carbon nanotubes (F-MWNTs) filled PMMA/PEO-A and PMMA/PEO-B composites were prepared via solution casting technique. The morphological study showed the formation of cracks in F-MWNTs/PMMA/PEO blend. The mechanical properties of PMMA/PEO blend were decrease by incorporation of F-MWNTs, which might be due to less compatibility between F-MWNTs and PMMA/PEO blends. Neat PEO upon crystallization showed distinct sized spherulites, which decreased by the incorporation o F-MWNTs (nucleation effect of FMWNTs). The X-ray diffraction (XRD) analyses revealed that the intensity of peaks decreased by incorporation of nanotubes, which means that the PEO crystallinity was suppressed in the presence of F-MWNTs. The thermal stabilities of PMMA/PEO blend were improved by incorporation of F-MWNTs.

Poli (metacrilato de metilo) (PMMA)/óxido de etileno Poli (PEO) (15% en peso. PMMA/85% en peso PEO (PMMA/PEO-A) y 30 en peso PMMA/70% en peso.% PEO (PMMA/PEO-B)), mezclas y nanotubos de carbono de pared múltiple funcionalizados (F-MWNTs) PMMA/PEO-A y PMMA/PEO-B fueron preparados mediante la técnica de fundición solución. El estudio morfológico mostró la formación de grietas en la mezcla F-MWNTs/PMMA/PEO. Las propiedades mecánicas de mezcla PMMA/PEO se redujeron mediante la incorporación de F-MWNT, lo que podría deberse a una menor compatibilidad entre F-MWNT y de las mezclas de PMMA/PEO. PEO por cristalización mostró esferulitas de distintos tamaños, que disminuyeron en la incorporación de F-MWNT (efecto de nucleación de FMWNTs). La difracción de rayos X (DRX) revelaron que la intensidad de los picos disminuyó mediante la incorporación de nanotubos, lo que significa que la cristalinidad de PEO fue suprimida en presencia de F-MWNT. Las estabilidades térmicas de mezcla de PMMA/PEO se mejoraron mediante la incorporación de F-MWNT.

Composite materials of Coal ash/ Poly(Methyl Methacrylate) (ash/PMMA) were prepared/synthesized and their properties were studied by scanning electron microscopy (SEM), polarized optical microscopy (POM), differential scanning calorimetry (DSC), thermogravimetric analyzer (TGA) and universal testing machine (UTM). The morphological study presented that the ash particles were well dispersed and embedded within the PMMA matrix. The DSC thermograms showed that the melting temperature (Tm) of pure PMMA is about 166 ºC which was shifted towards lower temperature when ash were incorporated in the polymer matrix. The mechanical properties of the ash/PMMA composites were enhanced up to an optimum level (ash 3 wt %) and then decreased at higher incorporation of large quantity of filler. The TGA thermograms indicated that the thermal stability of the ash/PMMA composite was enhance significantly than pure PMMA.

Polycaprolacton (PCL) and multiwalled carbon nanotubes/PCL (P-MWNT/PCL) were prepared by electrospinning technique. The average diameter of the nanofibers was below 400 nm. The mechanical properties of the P-MWNT/PCL nanofibers were higher than that of neat PCL nanofibers. It was also found that the mechanical properties of the composite nanofibers were decreased as increased the amount of P-MWNTs, which were due to the poor dispersion of the P-MWNTs in the PCL matrix or agglomeration of MWNTs at high concentration. The thermal stability of the P-MWNT/PCL nanofibers was higher than PCL nanofibers. The conductivity of the adsorbed P-MWNT on PCL (<p) nanofibers was 1.27 x 10-4 S/cm.