Comparison of Novel Conductive Open- and Closed-Porous PPy-PLA Composites

2009 ◽  
Author(s):  
Christine Chan ◽  
Ellen Chan ◽  
Weijia Zhang ◽  
Hani E. Naguib
Keyword(s):  
Relative Density ◽  
In Situ Polymerization ◽  
Compression Molding ◽  
Salt Leaching ◽  
Conductive Composites ◽  
Order Of Magnitude ◽  
Density Values ◽  
Average Size ◽  
Porous Composites

This study compared the fabrication techniques and characterization of novel open- and closed-porous structures in PPy-PLA conductive composites. For the open-porous composites, PLA samples were fabricated using compression molding and salt leaching with varying salt-to-polymer mass ratios, which were subsequently coated with PPy by in situ polymerization of pyrrole and iron (III) chloride. For the closed-porous composites, a patterned structure of PPy within PLA was created using compression molding of PPy-coated PLA pellets, followed by gas saturation and foaming techniques in order to create the closed pores. Characterization of both porous composites included their physical, mechanical, and electrical properties. Results showed that the modulus increased with increasing relative density and decreasing open porosity. The open-porous composites had lower relative density values but higher open porosities compared to the closed-porous composites. The average size of the closed pores was approximately an order of magnitude larger than the open pores. Lastly, the open-porous composites had higher conductivity values than the closed-porous composites due to the greater surface area of the continuous conductive pathway. The comparisons between open- and closed-porous composites established their characteristic properties for their future development in applications.

Development and Characterization of Novel Conductive Polypyrrole-Polylactide Open-Porous Composites

2009 ◽  
Author(s):  
Christine Chan ◽  
Weijia Zhang ◽  
Hani E. Naguib
Keyword(s):  
In Situ Polymerization ◽  
Compression Molding ◽  
Mass Ratio ◽  
Uncoated Sample ◽  
Salt Leaching ◽  
Mechanical And Electrical Properties ◽  
Mass Ratios ◽  
Porous Composites

Novel polypyrrole-polylactide blends were fabricated and characterized using compression molding, salt leaching, and in situ polymerization. Open-porous polylactide samples were fabricated using compression molding and salt leaching techniques with varying salt-to-polymer mass ratios of 3:1, 6:1, and 9:1. The samples then underwent in situ polymerization of pyrrole and iron (III) chloride to obtain a uniform coating of polypyrrole. Characterization of these novel composites comprised of their physical, mechanical, and electrical properties. With increasing salt-to-polymer mass ratio, it was found that the relative density decreased, the open porosity increased while pore size and pore density generally remained independent. The polypyrrole coating did not have a significant effect on the structure of the pore network. Microscopic polypyrrole nodules were observed to be uniformly coated on the surface and sub-surface of the composites. The compressive modulus decreased with increasing salt-to-polymer mass ratios. In addition, the modulus of the coated 3:1 salt-to-polymer mass ratio sample was twice the value obtained for the uncoated sample while the modulus values for the 6:1 and 9:1 samples did not significantly change. The conductivity increased as the salt-to-polymer mass ratio increased. The relationships observed between the structure and resulting properties provided the basis for future development and characterization of these novel porous composites.

Study on the Synthesis and Characterization of PANi/Nano-CeO2 Composites

2007 ◽  
Vol 124-126 ◽  
pp. 287-290 ◽  
Author(s):  
Fei Liu ◽  
Yong Jun He ◽  
Jeung Soo Huh
Keyword(s):  
In Situ Polymerization ◽  
Solid Phase ◽  
Polymerization Reaction ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Average Size

The nano-CeO2 was synthesized by two-step solid-phase reaction. The image of TEM showed that nano-CeO2 with an average size of about 70 nm. The series of polyaniline/nano-CeO2 composites with different PANi: CeO2 ratios were prepared by in-situ polymerization in the presence of hydrochloric acid (HCl) as dopant by adding nano-CeO2 into the polymerization reaction mixture of aniline. The composites obtained were characterized by FT-IR and UV-vis spectroscopy analysis. The FT-IR spectra of nanocomposites indicate different blue-shifts, attributed to C–N stretching mode for benzenoid unit. The UV-vis spectra of nanocomposites display einstein-shifts compared with PANi at 620nm. The conductivity properties of the composites are also changed compare to the pure PANi. These results suggest that the interactions between the polymer matrix and nanoparticles take place in polyaniline/nano- CeO2 composites.

scholarly journals Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 303
Author(s):  
Rokayya Sami ◽  
Schahrazad Soltane ◽  
Mahmoud Helal
Keyword(s):  
Ph Value ◽  
Silica Nanoparticle ◽  
Morphological Characterization ◽  
Aerobic Bacteria ◽  
Nano Materials ◽  
Elongation At Break ◽  
Stable Suspension ◽  
Average Size ◽  
Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

SPM Characterization of Substrate Surfaces Prepared for Carbon-Related-Film Deposition

1999 ◽  
Vol 587 ◽  
Author(s):  
Kazumasa Narumi ◽  
Shunya Yamamoto ◽  
Hiroshi Naramoto
Keyword(s):  
Annealing Temperature ◽  
Temperature Characteristic ◽  
Film Deposition ◽  
Annealing Conditions ◽  
Atomic Force ◽  
Surface Steps ◽  
Order Of Magnitude ◽  
Reducing Environment ◽  
Substrate Surfaces

AbstractsVariation of surface steps on sapphire (0001) and (1120) substrates processed with thermal annealing in air or a reducing environment at 1000 to 1400°C for 1 to 10 hours were investigated with an atomic force microscope (AFM). The annealed (0001) surfaces consist of atomically smooth and large terraces and atomic-height steps, whose configurations strongly depend on annealing conditions. On the (1120) surfaces, where crystallographic misorientation is almost an order of magnitude larger than that of the (0001) surfaces, step height and terraces increase in size with the longer annealing time and higher annealing temperature. Characteristic step figures due to the symmetry of atomic arrangement were observed on the (0001) surface.

scholarly journals Order-of-magnitude multiphoton signal enhancement based on characterization of absorption spectra of immersion oils at the 1700-nm window

2017 ◽  
Vol 25 (6) ◽  
pp. 5909 ◽  
Author(s):  
Ke Wang ◽  
Wenhui Wen ◽  
Yuxin Wang ◽  
Kai Wang ◽  
Jiexing He ◽  
...  
Keyword(s):  
Absorption Spectra ◽  
Signal Enhancement ◽  
Order Of Magnitude

Development and Characterization of Quercetin Loaded Nanoparticle for Skin Cancer

2019 ◽  
Vol 32 (1) ◽  
pp. 1-6
Author(s):  
Nikita Verma
Keyword(s):  
Skin Cancer ◽  
Drug Loading ◽  
Quadratic Model ◽  
Precipitation Method ◽  
Dietary Flavonoid ◽  
Ultraviolet Ray ◽  
Average Size ◽  
Different Characteristics ◽  
Polymer Ratio

As a disease skin cancer has obtained different characteristics over the decades. Solar radiation that contains ultraviolet ray is the prime cause of skin cancer. In this present research, the nano-precipitation method was applied for preparing Quercetin loaded Nanoparticle (Qu-Nps) with much enhanced loading properties and improves incorporation of corresponding drugs. At the same time, the Quadratic model that takes help of the Response Surface Method was applied to observe the effects of some specific parameters maintained in the development of nanoparticle. Here, the sonication time was 20 min and delivery system F6 (with Drug: Polymer ratio of 1:45) provided optimum drug entrapment ability which is 70%. The optimized formulation for average size was almost 102.39 ±7.64 nm with zeta potential diameter averaging -28.43mV. Quercetin is a dietary flavonoid possessing multidimensional properties that is used in various other diseases including viral infection, bacterial infection, diabetes mellitus, and cancer. All outcomes support the view that Quercetin loaded nanoparticles (Qu-Nps) has high entrapment and drug loading abilities.

Synthesis and characterization of Au, Pt supported on graphene aerogel catalysts for CO oxidation at low temperature

2021 ◽  
Vol 11 (1) ◽  
pp. 118-122
Author(s):  
Chuyen Phan Thi ◽  
Hang Tran Thi Thanh ◽  
Phong Pham Nam ◽  
Ha Vu Thi Thu
Keyword(s):  
Low Temperature ◽  
Ambient Temperature ◽  
Co Oxidation ◽  
Pt Nanoparticles ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Graphene Aerogel ◽  
Highly Dispersed ◽  
Average Size

Au, Pt supported on graphene aerogel catalysts (PtAu/rGOA) with molar ratio of Pt and Au of 1:1, and total metal concentration of 5 % were successfully synthesized by hydrothermal method.  The obtained catalysts were characterized by Raman, XRD, XPS, HR-TEM, BET. It revealed that Au and Pt nanoparticles with average size of 3 – 5 nm were highly dispersed on aerogel graphene. The activity of these catalysts was tested  in CO oxidation. The results showed that the conversion of CO at ambient temperature was 100% during 25 minutes. Accordingly, PtAu/rGOA could be considered as a potential catalysts for CO oxidation at low temperature.

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