Thermo-mechanical degradation-induced grafting of poly(styrene–acrylonitrile) to chlorinated polyethylene

2012 ◽  
Vol 97 (5) ◽  
pp. 766-770 ◽  
Author(s):  
Peng Luo ◽  
Guozhang Wu
Author(s):  
Gudrun A. Hutchins

In order to optimize the toughening effect of elastomers in engineering polymers, it is necessary to characterize the size, morphology and dispersion of the specific elastomer within the polymer matrix. For unsaturated elastomers such as butadiene or isoprene, staining with osmium tetroxide is a well established procedure. The residual carbon-carbon double bond in these materials is the reactive site and forms a 1,2-dilato complex with the OsO4. Incorporation of osmium tetroxide into the elastomer not only produces sufficient contrast for TEM, but also crosslinks the elastomer sufficiently so that ultramicrotomy can be accomplished at room temperature with minimal distortion.Blends containing saturated elastomers such as butyl acrylate (BA) and ethylene propylene diene monomer (EPDM) cannot be stained directly with OsO4 because effective reaction sites such as C=C or -NH2 are not available in sufficient number. If additional reaction sites can be introduced selectively into the elastomer by a chemical reaction or the absorption of a solvent, a modified, two-step osmium staining procedure is possible.


TAPPI Journal ◽  
2018 ◽  
Vol 17 (01) ◽  
pp. 31-37
Author(s):  
Bryan McCulloch ◽  
John Roper ◽  
Kaitlin Rosen

Barrier coatings are used in applications including food packaging, dry goods, and consumer products to prevent transport of different compounds either through or into paper and paperboard substrates. These coatings are useful in packaging to contain active ingredients, such as fragrances, or to protect contents from detrimental substances, such as oxygen, water, grease, or other chemicals of concern. They also are used to prevent visual changes or mechanical degradation that might occur if the paper becomes saturated. The performance and underlying mechanism depends on the barrier coating type and, in particular, on whether the barrier coating is designed to prevent diffusive or capillary transport. Estimates on the basis of fundamental transport phenomena and data from a broad screening of different barrier materials can be used to understand the limits of various approaches to construct barrier coatings. These estimates also can be used to create basic design rules for general classes of barrier coatings.


1973 ◽  
Vol 1 (4) ◽  
pp. 354-362 ◽  
Author(s):  
F. R. Martin ◽  
P. H. Biddison

Abstract Treads made with emulsion styrene-butadiene copolymer (SBR), solution SBR, polybutadiene (BR), and a 60/40 emulsion SBR/BR mixture were built as four-way tread sections on G78-15 belted bias tires, which were driven over both concrete and gravel-textured highways and on a small, circular, concrete test track. The tires were front mounted. When driven on concrete highway, all except the BR tread had either crumbled- or liquid-appearing surfaces, thought to have been formed by mechanical degradation or fatigue. When cornered on concrete, these materials formed small cylindrical particles or rolls. The BR tread had a smooth, granular-textured surface when driven on concrete highway and a ridge or sawtooth abrasion pattern when cornered on concrete. All the materials appeared rough and torn when run on gravel-textured highway. The differences in wear surface formed on BR tread and the other three are thought to be due primarily to the relatively high resilience of BR.


2019 ◽  
Author(s):  
Florian Strauss ◽  
Lea de Biasi ◽  
A-Young Kim ◽  
Jonas Hertle ◽  
Simon Schweidler ◽  
...  

Measures to improve the cycling performance and stability of bulk-type all-solid-state batteries (SSBs) are currently being developed with the goal of substituting conventional Li-ion battery (LIB) technology. As known from liquid electrolyte based LIBs, layered oxide cathode materials undergo volume changes upon (de)lithiation, causing mechanical degradation due to particle fracture, among others. Unlike solid electrolytes, liquid electrolytes are somewhat capable of accommodating morphological changes. In SSBs, the rigidity of the materials used typically leads to adverse contact loss at the interfaces of cathode material and solid electrolyte during cycling. Hence, designing zero- or low-strain electrode materials for application in next-generation SSBs is desirable. In the present work, we report on novel Co-rich NCMs, NCM361 (60% Co) and NCM271 (70% Co), showing minor volume changes up to 4.5 V vs Li<sup>+</sup>/Li, as determined by <i>operando</i> X-ray diffraction and pressure measurements of LIB pouch and pelletized SSB cells, respectively. Both cathode materials exhibit good cycling performance when incorporated into SSB cells using argyrodite Li<sub>6</sub>PS<sub>5</sub>Cl solid electrolyte, albeit their morphology and secondary particle size have not yet been optimized.


2019 ◽  
Author(s):  
Florian Strauss ◽  
Lea de Biasi ◽  
A-Young Kim ◽  
Jonas Hertle ◽  
Simon Schweidler ◽  
...  

Measures to improve the cycling performance and stability of bulk-type all-solid-state batteries (SSBs) are currently being developed with the goal of substituting conventional Li-ion battery (LIB) technology. As known from liquid electrolyte based LIBs, layered oxide cathode materials undergo volume changes upon (de)lithiation, causing mechanical degradation due to particle fracture, among others. Unlike solid electrolytes, liquid electrolytes are somewhat capable of accommodating morphological changes. In SSBs, the rigidity of the materials used typically leads to adverse contact loss at the interfaces of cathode material and solid electrolyte during cycling. Hence, designing zero- or low-strain electrode materials for application in next-generation SSBs is desirable. In the present work, we report on novel Co-rich NCMs, NCM361 (60% Co) and NCM271 (70% Co), showing minor volume changes up to 4.5 V vs Li<sup>+</sup>/Li, as determined by <i>operando</i> X-ray diffraction and pressure measurements of LIB pouch and pelletized SSB cells, respectively. Both cathode materials exhibit good cycling performance when incorporated into SSB cells using argyrodite Li<sub>6</sub>PS<sub>5</sub>Cl solid electrolyte, albeit their morphology and secondary particle size have not yet been optimized.


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