Polymer-Sulfur Composites

Wang J, Yang J, Xie J, Xu N (2002) A novel conductive polymer—sulfur composite cathode material for rechargeable lithium batteries. Adv Mater 14 963-965... 

That is, the analysis of the received results, has shown an opportunity of equal-mass replacement of the traditional activator - zinc oxide on the new polymer - inorganic composite (5,0 phr) at maintenance of a high activation level of sulfur vulcanization process of rubber mixes on the basis of diene isoprene rubber and improvement of the physical-mechanical properties complex of their vulcanizates. 

The stabilizing action of sulfur-containing compoimds is related to their ability to decompose peroxide and hydroperoxide groups without the formation of free radicals, as well as to their property of terminating the reaction chains in the decomposition of polymers. Sulfur-containing compounds are used in practice as thermal stabilizers, since many of them prove to be insufficiently stable to the action of ultraviolet light and can cause sensitized decomposition of the poljmaer when the composition is irradiated. There is information that the activity of mercapto derivatives, in particular, dodecyl mercaptan, in the process of thermal decomposition of pol5Tvinyl chloride, does not decrease when the temperature is raised to 190-200°C [278]. 

The ability to probe surfaces using in situ SERS can be exploited in polymer chemistry to characterise the surface of polymers for comparison with the bulk properties and to study polymer-metal composites such as adhesives and coatings. Interactions between adhesives and metal polymeric surfaces have been investigated [437]. The applicability of SERS to polymer surfaces has also been reported in a study on poly-/ -nitrostyrene [438], and in another study on the effects of chromic/sulfuric acid etching on PE films [439]. The desired surface sensitivity... 

Zhou WD, Yu YC, Chen H, DiSalvo FJ, Abruna HD (2013) J Am Chem Soc 135 16736 Wang X, Zhang Z, Yan X, Qu Y, Lai Y, Li J (2015) Interface polymerization synthesis of conductive polymer/graphite oxide sulfur composites for high-rate lithium-sulfur batteries. 

Rajagopalan etal. [4] reported the synthesis of sulphonated polyetherimide and subsequent synthesis of ionic polymer metal composites (IPMC) by depositing platinum on both sides of the polymer membrane by electroless plating process for use in actuators. The TGA and NMR analysis confirmed the successful incorporation of sulfonic groups in the polymer backbone. The content of sulfur in the polymer membrane was measured to be 4.68% by EDX analysis and the degree of sulfonation could also be controlled. SEM micrographs of the composite membrane also confirmed the uniform formation of small platinum particles on the surface of polymer membrane as shown in Figure 1.5. The thickness of... 

Zhu et al ° reported the esterification of acetic add and ethanol in a tube-and-sheU type reactor, using a polymer-ceramic composite membrane obtained by dip-coating a ceramic support tube with a hydrophilic poly-etherimide. Reactants, along with sulfuric add as homogeneous catalyst, were fed in the tube side while a vacuum was applied to the shell side. 

The polyamides are soluble in high strength sulfuric acid or in mixtures of hexamethylphosphoramide, /V, /V- dim ethyl acetam i de and LiCl. In the latter, compHcated relationships exist between solvent composition and the temperature at which the Hquid crystal phase forms. The polyamide solutions show an abmpt decrease in viscosity which is characteristic of mesophase formation when a critical volume fraction of polymer ( ) is exceeded. The viscosity may decrease, however, in the Hquid crystal phase if the molecular ordering allows the rod-shaped entities to gHde past one another more easily despite the higher concentration. The Hquid crystal phase is optically anisotropic and the texture is nematic. The nematic texture can be transformed to a chiral nematic texture by adding chiral species as a dopant or incorporating a chiral unit in the main chain as a copolymer (30). 

A variety of materials has been proposed to modify the properties of asphaltic binders to enhance the properties of the mix (112), including fillers and fibers to reinforce the asphalt—aggregate mixture (114), sulfur to strengthen or harden the binder (115,116), polymers (98,117—121), mbber (122), epoxy—resin composites (123), antistripping agents (124), metal complexes (125,126), and lime (127,128). AH of these additives serve to improve the properties of the binder and, ultimately, the properties of the asphalt—aggregate mix. 

Poly(phenylene sulfide) (PPS) is another semicrystalline polymer used in the composites industry. PPS-based composites are generally processed at 330°C and subsequently cooled rapidly in order to avoid excessive crystallisation and reduced toughness. The superior fire-retardant characteristics of PPS-based composites result in appHcations where fire resistance is an important design consideration. Laminated composites based on this material have shown poor resistance to transverse impact as a result of the poor adhesion of the fibers to the semicrystalline matrix. A PPS material more recently developed by Phillips Petroleum, AVTEL, has improved fiber—matrix interfacial properties, and promises, therefore, an enhanced resistance to transverse impact (see PoLYAffiRS containing sulfur). 

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