Polyketone Nanocomposites by Palladium-Catalyzed Ethylene-Carbon Monoxide-(Propene) Co(Ter)polymerization Inside an Unmodified Layered Silicate

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Hamish A. Miller ◽  
Simonetta Moneti ◽  
Francesco Vizza ◽  
Elisa Passaglia ◽  
Claudio Bianchini ◽  
...  
Keyword(s):  
Morphological Analysis ◽  
Layered Silicate ◽  
Melt Mixing ◽  
Methanol Solutions ◽  
Polar Media ◽  
Palladium Catalyzed ◽  
Preliminary Study ◽  
Thermal Stability Of ◽  
Nanocomposite Structures

AbstractComposites from Na-montmorillonite with a content in inorganic material ranging from 3 to 98 wt % were prepared in situ either by copolymerization of ethylene and CO or by terpolymerization of ethylene, propene and CO using a palladium(II) catalyst modified with 1,3-bis(diphenylphosphino)propane. This catalytic system is active in polar media and allowed to produce nanocomposites starting from unmodified Na-montmorillonite in water-methanol solutions. The morphological analysis, performed on samples with less than 40 wt % silicate by XRD and TEM, showed the formation of either intercalated or exfoliated (nanocomposite) structures, depending on the initial amount of the layered silicate in the reactor as well as the presence of propene as comonomer. Improved thermal stability of the hybrid materials, as compared to the corresponding organic polymers, was shown by TGA. A preliminary study of the blending of some polyketone nanocomposites with polyamide (nylon-6) was carried out by melt mixing at high temperature in a Brabender mixer.

scholarly journals Highly Enhancing Electrical, Thermal, and Mechanical Properties of Polypropylene/Graphite Intercalation Compound Composites by In Situ Expansion during Melt Mixing

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3095
Author(s):  
Zhifeng Wang ◽  
Jun Tong ◽  
Wei Li ◽  
Haichen Zhang ◽  
Manfeng Hu ◽  
...  
Keyword(s):  
Intercalation Compound ◽  
Interlamellar Spacing ◽  
Graphite Intercalation Compound ◽  
Thermal And Mechanical Properties ◽  
Melt Mixing ◽  
Graphite Intercalation ◽  
Different Temperatures ◽  
Thermal Stability Of ◽  
Nucleation Point

Polypropylene/graphite intercalation compound (PP/GIC) composites are prepared via melt mixing at three different temperatures (180, 200, and 220 °C). The dispersion of GICs in the composites is clearly improved due to the increased interlamellar spacing caused by in situ expansion of GICs at higher temperatures, which facilitates the intercalation of PP molecular chains into the GIC galleries. As a result, the PP/GIC composite with 10 wt% GICs prepared at 220 °C (PG220) presents a dielectric constant of about 1.3 × 108 at 103 Hz, which is about six orders higher than that of the composite prepared at 180 °C (PG180). Moreover, the thermal conductivity of the PG220 sample (0.63 Wm−1K−1) is 61.5% higher than that of the PG180 sample. The well-dispersed GICs accelerates the crystallization of PP by increasing the nucleation point and enhances the thermal stability of the composites. The PG220 sample shows a Young’s modulus that is about 21.2% higher than that of the PG180 samples. The results provide an efficient approach for fabricating polymer/GIC composites without complex exfoliation and dispersion processes.

In situ compatibilization of a polyetherimide and a thermotropic polyester using an epoxy resin

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Antonio Turturro ◽  
Maila Castellano ◽  
Gianluca Panzardi ◽  
Barbara Valenti ◽  
Saverio Russo ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Morphological Analysis ◽  
Tensile Modulus ◽  
Crystalline Polymer ◽  
Ternary Blends ◽  
Electron Microscopic ◽  
Melt Mixing

Abstract This study examines the compatibilization of the polyetherimide Ultem 1000 with the thermotropic liquid crystalline polymer Vectra A 950 by using an epoxy resin (PKFE) as compatibilizer. IR spectroscopy and electron-microscopic morphological analysis indicate the grafting of PKFE molecules on fibrillar domains of Vectra during melt mixing. Moreover, morphological analysis shows that the addition of PKFE improves the dispersion and decreases the size of Vectra fibrils. Both Vectra and PKFE significantly reduce the glass transition temperature of Ultem in ternary blends. The tensile modulus and the ultimate strength of the blends are improved with respect to those of neat Ultem. However, the final materials are very fragile. The roles of Vectra and PKFE are discussed.

scholarly journals Antimicrobial Property of Polypropylene Composites and Functionalized Copper Nanoparticles

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1694
Author(s):  
Noemi Jardón-Maximino ◽  
Gregorio Cadenas-Pliego ◽  
Carlos A. Ávila-Orta ◽  
Víctor Eduardo Comparán-Padilla ◽  
Luis E. Lugo-Uribe ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Crystallization Process ◽  
Copper Ions ◽  
Antimicrobial Property ◽  
Aminobutyric Acid ◽  
New Materials ◽  
Melt Mixing ◽  
Polypropylene Composites ◽  
And Staphylococcus Aureus ◽  
Thermal Stability Of

Copper nanoparticles (CuNPs) functionalized with polyethyleneimine (PEI) and 4-aminobutyric acid (GABA) were used to obtain composites with isotactic polypropylene (iPP). The iPP/CuNPs composites were prepared at copper concentrations of 0.25–5.0 wt % by melt mixing, no evidence of oxidation of the CuNP was observed. Furthermore, the release of copper ions from iPP/CuNPs composites in an aqueous medium was studied. The release of cupric ions was higher in the composites with 2.5 and 5.0 wt %. These composites showed excellent antibacterial activity (AA) toward Pseudomona aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). The incorporation of CuNP into the iPP polymeric matrix slightly decreased the thermal stability of the composite material but improved the crystallinity and the storage modulus. This evidence suggests that CuNPs could work as nucleating agents in the iPP crystallization process. The iPP/CuNPs composites presented better AA properties compared to similar composites reported previously. This behavior indicates that the new materials have great potential to be used in various applications that can be explored in the future.

Preliminary Study on In Situ Realtime Quantitation of Target Bacteria on the Principle of Flow Cytometry

2017 ◽  
Vol 262 ◽  
pp. 224-227
Author(s):  
Gen Murakami ◽  
Yuichi Sugai ◽  
Kyuro Sasaki
Keyword(s):  
Flow Cytometry ◽  
Bacterial Culture ◽  
Scattered Light ◽  
Bacterial Suspension ◽  
Culture Solution ◽  
Bacterial Cells ◽  
Monitoring Wells ◽  
Measurement Principle ◽  
Preliminary Study

In-situ realtime method that can monitor the target bacteria should be used to determine the real situation of the bacteria in deep parts of heaps in heap bioleaching plants. This study suggest to apply flow cytometry technology to in-situ realtime monitoring of target bacteria. Flow cytometry is a method that can rapidly quantify the bacterial cells in bacterial suspension based on the detection of lights that are emitted from bacterial cells. In this study, we estimated the possibility of the application of flow cytometry to the selective detection of target bacteria. The bacterial culture solution that had been diluted by water including other bacteria was provided for fluorescence spectral analysis and scattered light analysis that were functions of flow cytometry. Our target bacteria could be selectively detected by those analyses in this study, therefore, it was shown that the flow cytometry could be useful for detecting target bacteria selectively. Because the measurement principle of flow cytometry is quite simple, it can be expected to be installed into deep heaps through the monitoring wells and determine the dominance of target bacteria in-situ and realtime in the future.

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