A Review of In Situ Mechanical Characterization of Polymer Nanocomposites: Prospect and Challenges

2017 ◽  
Vol 69 (5) ◽  
Author(s):  
Samit Roy ◽  
John Ryan ◽  
Samantha Webster ◽  
Dhriti Nepal

Mechanics at the nanoscale is radically different from mechanics at the macroscale. Atomistic simulations have revealed this important fact, and experiments are being performed to support it. Specifically, in situ testing is being performed by researchers using different approaches with different material systems to interrogate the material at the nanoscale and prove or disprove many of the proposed models. This paper attempts to provide a fairly comprehensive review of the in situ testing that is being performed at the nanoscale, together with a brief description of the models that in situ testing are being used to verify. This review paper intends to primarily provide a broad snapshot of in situ testing of different nanocarbon-based polymeric nanocomposite materials.

2018 ◽  
Author(s):  
Devon Jakob ◽  
Le Wang ◽  
Haomin Wang ◽  
Xiaoji Xu

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>


Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 721 ◽  
Author(s):  
Jorge A. Ramírez-Gómez ◽  
Javier Illescas ◽  
María del Carmen Díaz-Nava ◽  
Claudia Muro-Urista ◽  
Sonia Martínez-Gallegos ◽  
...  

Atrazine (ATZ) is an herbicide which is applied to the soil, and its mechanism of action involves the inhibition of photosynthesis. One of its main functions is to control the appearance of weeds in crops, primarily in corn, sorghum, sugar cane, and wheat; however, it is very toxic for numerous species, including humans. Therefore, this work deals with the adsorption of ATZ from aqueous solutions using nanocomposite materials, synthesized with two different types of organo-modified clays. Those were obtained by the free radical polymerization of 4-vinylpyridine (4VP) and acrylamide (AAm) in different stoichiometric ratios, using tetrabutylphosphonium persulfate (TBPPS) as a radical initiator and N,N′-methylenebisacrylamide (BIS) as cross-linking agent. The structural, morphological, and textural characteristics of clays, copolymers, and nanocomposites were determined through different analytical and instrumental techniques, i.e., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption kinetics experiments of ATZ were determined with the modified and synthesized materials, and the effect of the ratio between 4VP and AAm moieties on the removal capacities of the obtained nanocomposites was evaluated. Finally, from these sets of experiments, it was demonstrated that the synthesized nanocomposites with higher molar fractions of 4VP obtained the highest removal percentages of ATZ.


2015 ◽  
Vol 162 (14) ◽  
pp. F1461-F1469 ◽  
Author(s):  
Alireza Sadeghi Alavijeh ◽  
Ramin M.H. Khorasany ◽  
Zachary Nunn ◽  
Aronne Habisch ◽  
Michael Lauritzen ◽  
...  

Author(s):  
B. A. Samuel ◽  
Bo Yi ◽  
R. Rajagopalan ◽  
H. C. Foley ◽  
M. A. Haque

We present results on the mechanical properties of single freestanding poly-furfuryl alcohol (PFA) nanowires (aspect ratio &gt; 50, diameters 100–300 nm) from experiments conducted using a MEMS-based uniaxial tensile testing device in-situ inside the SEM. The specimens tested were pyrolyzed PFA nanowires (pyrolyzed at 800° C).


Sensors ◽  
2020 ◽  
Vol 20 (15) ◽  
pp. 4163
Author(s):  
Avi Karsenty

A comprehensive review of the main existing devices, based on the classic and new related Hall Effects is hereby presented. The review is divided into sub-categories presenting existing macro-, micro-, nanoscales, and quantum-based components and circuitry applications. Since Hall Effect-based devices use current and magnetic field as an input and voltage as output. researchers and engineers looked for decades to take advantage and integrate these devices into tiny circuitry, aiming to enable new functions such as high-speed switches, in particular at the nanoscale technology. This review paper presents not only an historical overview of past endeavors, but also the remaining challenges to overcome. As part of these trials, one can mention complex design, fabrication, and characterization of smart nanoscale devices such as sensors and amplifiers, towards the next generations of circuitry and modules in nanotechnology. When compared to previous domain-limited text books, specialized technical manuals and focused scientific reviews, all published several decades ago, this up-to-date review paper presents important advantages and novelties: Large coverage of all domains and applications, clear orientation to the nanoscale dimensions, extended bibliography of almost one hundred fifty recent references, review of selected analytical models, summary tables and phenomena schematics. Moreover, the review includes a lateral examination of the integrated Hall Effect per sub-classification of subjects. Among others, the following sub-reviews are presented: Main existing macro/micro/nanoscale devices, materials and elements used for the fabrication, analytical models, numerical complementary models and tools used for simulations, and technological challenges to overcome in order to implement the effect in nanotechnology. Such an up-to-date review may serve the scientific community as a basis for novel research oriented to new nanoscale devices, modules, and Process Development Kit (PDK) markets.


2007 ◽  
Vol 91 (7) ◽  
pp. 071919 ◽  
Author(s):  
Stéphane André ◽  
Christophe Baravian ◽  
Norbert Renault ◽  
Christian Cunat

Sign in / Sign up

Export Citation Format

Share Document