Quantitative electron tomography of polylactic acid/clay nanocomposites for better comprehension of processing–microstructure–elastic modulus

2020 ◽  
pp. 096739112093205
Author(s):  
Maider Iturrondobeitia ◽  
Julen Ibarretxe ◽  
Pello Jimbert ◽  
Roberto Fernandez-Martínez
Keyword(s):  
Electron Tomography ◽  
Poly Lactic Acid ◽  
Clay Nanocomposites ◽  
X Ray Diffraction ◽  
Quantitative Characterization ◽  
Tem Analysis ◽  
Clay Particles ◽  
X Ray ◽  
Shear Rates ◽  
Transmission Electron

The objective of performing transmission electron microscopy (TEM) tomography (TEMT) on poly (lactic acid) (PLA)/clay samples is to characterize their 3D microstructure by obtaining the dispersion distribution and orientation of the dimensions of the clays. This information cannot be elucidated from a qualitative TEM analysis or from conventional characterization techniques such as X-ray diffraction. The nanocomposites are obtained by mixing PLA with Cloisite 20A and 30B at different extrusion shear rates which have been analyzed in 3D. Quantitative TEMT is performed to all the nanocomposites and the resulting 3D quantitative characterization (geometry of clay particles misalignment degree and distribution) is used for a more realistic comprehension of the mechanical behavior of the nanocomposites.

Preparation and Characterization of Poly(lactic acid)/Difatty Acyl Urea/Modified Clay Nanocomposite

2011 ◽  
Vol 364 ◽  
pp. 81-85 ◽  
Author(s):  
Emad A. Jaffar Al-Mulla
Keyword(s):  
Lactic Acid ◽  
Casting Process ◽  
Poly Lactic Acid ◽  
X Ray Diffraction ◽  
Clay Particles ◽  
X Ray ◽  
Modified Clay ◽  
Clay Modification ◽  
Transmission Electron

In this study, difatty acyl urea (DFAU), synthesized from palm oil, and natural clay (sodium montmorillonite) were used to prepare organoclay (OMMT). The clay modification was carried out by stirring the clay particles in an aqueous solution of DFAU at which the clay layer thickness increased from 1.25 to 2.82. This OMMT was then used for nanocomposite production to improve the property balance of poly (lactic acid) (PLA) by solution casting process. The nanocomposite was characterized using various apparatuses. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results confirmed the production of nanocomposite. PLA modified clay nanocomposite shows higher thermal stability and significant improvement of mechanical properties in comparison with pure PLA. The use of DFAU as a modifier will reduce the dependence on petroleum-based surfactant. In addition to its applications such as films and textile fibers, this nanocomposite represents a good candidate to produce disposable packaging because they have good mechanical, thermal properties, fabricability and processability.

scholarly journals Bioactivities of Geranium wallichianum Leaf Extracts Conjugated with Zinc Oxide Nanoparticles

Biomolecules ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 38 ◽  
Author(s):  
Banzeer Ahsan Abbasi ◽  
Javed Iqbal ◽  
Riaz Ahmad ◽  
Layiq Zia ◽  
Sobia Kanwal ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Energy Dispersive ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Leaf Extracts ◽  
Tem Analysis ◽  
X Ray ◽  
Transmission Electron

This study attempts to obtain and test the bioactivities of leaf extracts from a medicinal plant, Geranium wallichianum (GW), when conjugated with zinc oxide nanoparticles (ZnONPs). The integrity of leaf extract-conjugated ZnONPs (GW-ZnONPs) was confirmed using various techniques, including Ultraviolet–visible spectroscopy, X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, energy-dispersive spectra (EDS), scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The size of ZnONPs was approximately 18 nm, which was determined by TEM analysis. Additionally, the energy-dispersive spectra (EDS) revealed that NPs have zinc in its pure form. Bioactivities of GW-ZnONPs including antimicrobial potentials, cytotoxicity, antioxidative capacities, inhibition potentials against α-amylase, and protein kinases, as well as biocompatibility were intensively tested and confirmed. Altogether, the results revealed that GW-ZnONPs are non-toxic, biocompatible, and have considerable potential in biological applications.

Synthesis and Electrorheological Characteristics of Conducting Polymer/Clay Nanocomposites

2007 ◽  
Vol 124-126 ◽  
pp. 1083-1086
Author(s):  
Jun Hee Sung ◽  
Hyoung Jin Choi
Keyword(s):  
Conducting Polymer ◽  
Electrorheological Fluid ◽  
Clay Nanocomposites ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Internal Structures ◽  
In Situ Emulsion Polymerization

Nanocomposites of conducting polymers of polyaniline (PANI), poly(oethoxyaniline) (PEOA) and polypyrrole (PPy) with clay prepared via either in-situ emulsion polymerization or solvent intercalation were investigated especially for electrorheological fluid (ER) application. Internal structures of these nanocomposites were examined via wide angle X-ray diffraction (WAXD), and transmission electron microscope (TEM). The intercalated nanostructures analyzed via WAXD and TEM were correlated with the electrical property change originated from the nanoscale interaction between clay and conducting polymer. Moreover, their ER behaviors were measured via rotational rheometer with external electric field controller.

TEM Analysis on Bio-Functional Gradient Hydroxyapatite/ZrO2 Coatings

2007 ◽  
Vol 336-338 ◽  
pp. 1676-1678
Author(s):  
Cheng Yun Ning ◽  
Ying Jun Wang ◽  
Xiao Feng Chen ◽  
Jian Dong Ye ◽  
Gang Wu ◽  
...  
Keyword(s):  
Net Energy ◽  
X Ray Diffraction ◽  
Tem Analysis ◽  
X Ray ◽  
Amorphous Phases ◽  
Functional Gradient ◽  
Transmission Electron ◽  
Gradient Coatings ◽  
Means Of Transmission ◽  
Sprayed Coatings

In the present study, bioactive functional gradient coatings were prepared using net-energy controlled plasma spraying technology. The microstructure and phases of the bioactive functional gradient coating were examined by means of transmission electron microscope, scanning electron microscopy and X-ray diffraction. The results revealed that: (1) as-sprayed coatings contained a large amount of amorphous phases and some nano-sized HA crystals formed during rapid solidification, (2) surface of the coating was very rough with different-sized micropores, and the gradient layer was much denser which firmly bonded to the substrate without gaps and obvious interface between the coating and the substrate

Modification of clays with styrenic ionic liquid by Synthesis of in-situ Polystyrene Nanocomposite

e-Polymers ◽  
2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Mohammad Galehassadi ◽  
Fatemeh Hosseinzadeh ◽  
Mehrdad Mahkam
Keyword(s):  
Electron Microscopy ◽  
Ionic Liquid ◽  
Clay Nanocomposites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Modified Montmorillonite ◽  
Transmission Electron ◽  
Insitu Polymerization ◽  
Thermal Stability Of

Abstract Nanocomposites of polystyrene (PS) was prepared with new styrenic ionic liquid, N-(4-vinyl benzyl)-(N,N-dimethylamino) pyridinium chloride[VBMAP], surfactants used as organic modifications for the clays. Sodium montmorillonite (Na-MMT) was successfully modified by [VBMAP] to become OMMT through cation exchange technique which is shown by the increase of basalspacing of clay by XRD. The composite material based on polystyrene and organo-modified montmorillonite (OMMT) was prepared by insitu polymerization and characterized. The morphology of the polymer/clay hybrids was evaluated by X-ray diffraction (XRD) ,transmission electron microscopy (TEM) and scanning electron microscopy (SEM), showing good overall dispersion of the clay. The thermal stability of the polymer/clay nanocomposites were enhanced, as evaluated by thermogravimetric analysis.

Influence of Silicate Surface Modification on Morphology and Mechanical Properties of Nylon6/Clay Nanocomposites

2007 ◽  
Vol 334-335 ◽  
pp. 877-880 ◽  
Author(s):  
Jae Hun Shim ◽  
Jae Hun Choi ◽  
Jung Hiuk Joo ◽  
Jin San Yoon
Keyword(s):  
Tensile Properties ◽  
Nylon 6 ◽  
Clay Nanocomposites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
End Groups ◽  
Silicate Surface ◽  
Epoxy Groups ◽  
Microscopy Images

A new method was attempted to improve the interaction between nylon 6 with a commercially available organoclay, Cloisite®25A (C25A) through modification of C25A with 3-aminopropyltriethoxy silane, 3-(trimethoxysilyl)propyl methacrylate, 3-(glycidoxypropyl) trimethoxysilane and 3-isocyanate propyltriethoxy silane. C25A and C25A modified with the silane compounds(TFC) were melt mixed with nylon 6. X-Ray diffraction and transmission electron microscopy images revealed that all the TFC layers were fully exfoliated in nylon 6 matrix irrespectively of the type of the silane compounds used for the modification. Tensile properties of nylon 6 were most significantly improved when 3-(glycidoxypropyl)trimethoxysilane modified C25A was incorporated. The chemical reaction between the epoxy groups and the end groups of nylon 6 raised the interfacial interaction and thus was responsible for the enhanced tensile properties.

Study on the Preparation and Properties of EVA-G-PU/OMMT Nanocomposites

2010 ◽  
Vol 123-125 ◽  
pp. 247-250
Author(s):  
Yu Qing Zhang ◽  
Yu Xin He ◽  
Li Zhang ◽  
Jun Xian Li
Keyword(s):  
Electron Microscopy ◽  
Mechanical Analysis ◽  
Clay Nanocomposites ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Thermal Stabilities ◽  
X Ray ◽  
Transmission Electron ◽  
New Type

A new type of EVA-g-PU/OMMT nanocomposites was synthesized through the method of chemical modification and melt intercalation. FTIR testing showed that the PU prepolymer was grafted on EVA main chains successfully. The structures of EVA-g-PU/OMMT nanocomposites were characterized by X-ray diffraction (XRD) and by high-resolution transmission electron microscopy (HRTEM). The enhanced storage modulus of EVA-g-PU/OMMT nanocomposites was characterized by dynamic mechanical analysis (DMA). The thermal stabilities of EVA/clay nanocomposites were also studied by thermal gravimetric analysis (TGA). Mechanical testing showed that the tensile strength and tear strength of EVA-g-PU/OMMT nanocomposites were far superior to pure EVA.

Preparation of Highly Exfoliated Epoxy/Clay Nanocomposites by the Method of Ultrasonication Dispersion-Microwave Cure

2011 ◽  
Vol 418-420 ◽  
pp. 670-673 ◽  
Author(s):  
Kun Yan Wang ◽  
Shi Yang Zhou ◽  
Zhen Jiang ◽  
Xiao Qing Zhu
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Microwave Energy ◽  
Basal Spacing ◽  
Clay Nanocomposites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Second Stage ◽  
Transmission Electron ◽  
Layered Clay

A new ultrasonication dispersion – microwave cure (UD-MC) method for preparing highly exfoliated layered epoxy/clay nanocomposites was developed. The process was divided into two consecutive stages. In the first stage, the epoxy and organoclay were mixed by high stirring and ultrasonication in the presence of acetone. In the second stage, the mixture of epoxy and organoclay was cured with microwave of 400W and postcured at 135°C. The microstructure of the nanocomposites was characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicated that the basal spacing of the organoclay particles in the epoxy/clay mixture was significantly enlarged, up to around 75Å afther the ultrasonic treatment. The layered clay was highly exfoliated under the microwave energy; and the basal spacing of nanolayers was more than 90Å.

The Preparation and Characterization of a Novolac Cured Epoxy-Clay Nanocomposites

2006 ◽  
Vol 939 ◽  
Author(s):  
Tsung-Yen Tsai ◽  
Shau-Tai Lu ◽  
Chih-Hung Li ◽  
Chin-Jei Huang ◽  
Li-Chun Chen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Benzalkonium Chloride ◽  
Barrier Properties ◽  
Layered Silicates ◽  
Clay Nanocomposites ◽  
Crosslinking Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

ABSTRACTIntercalated or exfoliated nanocomposites were composed by the novolac cured epoxy and one of three different kinds of layered silicates, such as montmorillonite (PK-802), saponite (Semecton-SA) and nontronite (PK-805). The bi-functional modifiers (PI/BEN or MI/BEN) with different ratio, which contained one of the promoters (2-phenylimidazole, PI and 2-methylimidazole, MI) of epoxy and benzalkonium chloride (BEN), were intercalated into the gallery regions of pure clays at the same time and followed by a crosslinking reaction. The properties of novolac cured epoxy/clay nanocomposites were characterized by wild-angle X-ray diffraction (WAXRD), thermal analysis (TGA/DSC), coefficiency of thermal expansion (TMA), mechanical properties (DMA), and transmission electron microscopy (TEM). According to the measurement, these novolac cured epoxy-clay nanocomposites have shown the significant improvement in the thermal, mechanical and barrier properties.

Preparation of Exfoliated Polyethylene/Clay Nanocomposites at High Clay Content

2010 ◽  
Vol 150-151 ◽  
pp. 561-564
Author(s):  
Hao Qun Hong ◽  
Hai Yan Zhang ◽  
Hui He ◽  
De Min Jia
Keyword(s):  
Solid Phase ◽  
Clay Content ◽  
Layered Silicates ◽  
Clay Nanocomposites ◽  
Melt Blending ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
High Polarity

The polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by melt blending the organic MMT with the ternary-monomer graft copolymers of polyethylene (GPE) which were prepared by solid phase grafting maleic anhydride, methyl methacrylate and butyl acrylate onto PE. Fourier transform infrared spectroscopy was used to characterize the structure of GPE. X-ray diffraction patterns and transmission electron microscopy were used to characterize the morphology of GPE/MMT nanocomposites. Results showed that GPE was an outstanding polymeric material to prepare an exfoliated polymer/layered silicates nanocomposites due to the high polarity of GPE and high graft degree. Most layered silicates still maintain the exfoliated and well dispersed state even at 40 phr OMMT content. The exfoliation of layered silicates was attributed to the well intercalation and easy wetting of the grafted oligomers.

Sign in / Sign up

Export Citation Format

Share Document