Grafting cross linking

TEMPO Tentagel Teoc TES Tf TFA TFFH 2,2,6,6-tetramethyl-l-piperidinyloxy PEG-grafted cross-linked polystyrene 2-(trimethylsilyl)ethoxycarbonyl triethylsilane trifluoromethanesulfonyl trifluoroacetic acid tetramethylfluoroformamidinium hexafluorophosphate, [(Me2N)2CF] [P F ]... 

The reactive additives applied in this procedure are typically vinyl monomers and/or oligomers, with one or more double bond, capable of radiation initiated chain reactions. The reactive additives — applied in moderate concentrations, — may form short side-chains and this way cross-linking bridges between the components to be compatibilized. The whole process may also be considered as promoted cross-linking, or graft - cross-linking. 

PREPARATION, CHARACTERIZATION, AND EVAEUATION OF WATER-SWEELABEE HYDROGEE VIA GRAFTING CROSS-LINKED POLYACRYLAMIDE CHAINS ONTO GELATIN BACKBONE BY FREE RADICAL POLYMERIZATION... 

The structure and physical properties of the thermoplastic vulcanizates (TPE-V) produced in the process of the reactive processing of pol5rpropyl-ene (PP) and ethylene-octene elastomer (EOE) in the form of alloy, using the cross-linking system was analyzed. With the DMTA, SEM and DSC it has been demonstrated that the d5mamically produced vulcanizates constitute a typical dispersoid, where semicrystal PP produces a continuous phase, and the dispersed phase consists of molecules of the cross-linked ethylene-octene elastomer, which play a role of a modifier of the properties and a stabilizer of the two-phase structure. It has been found that the mechanical as well as the thermal properties depend on the content of the elastomer in the blends, exposed to mechanical strain and temperature. The best results have been achieved for grafted/cross-linked blends with the contents of iPP/EOE-55/45%. 

Padavan DT, Hamilton AM, Millon LE, Boughner DR, Wan W (2011) Synthesis, characterization and in vitro cell compatibility study of a poly(amic acid) graft/cross-linked poly(vinyl alcohol) hydrogel. Acta Biomater 7 258-267... 

Commercial impact-modified acrylic resins (Table 19.15) exhibit five- to tenfold improvement in the notched Izod impact strength and the ultimate tensile elongation compared to the neat PMMA resin. These impact-modified acrylics are usually blended captively by the manufacturers of the acrylic resins. The base resin in a typical weatherable grade (Plexiglas DR, Rohm and Haas) could be a methyl methacrylate copolymer with ethylacrylate and styrene, while the rubber additive (ca. 10 %) could be an emulsion-polymerized, PMMA-grafted, cross-linked poly (n-butylacrylate) rubber of controlled particle size (<200 nm). The nonweatherable impact-modified acrylic (XT, CYRO) typically consists of a MMA/S/AN copolymer with MBS (ca. 10 %) rubber particle dispersions. 

Influence of the content of elastomer Engage I on physical properties of TPE with PP and EOE modified (grafting/cross-linking) with a silane/ peroxide cross-linking system has been shown in Fig. 4.3 and Table 4.2. The content of comonomer had significant influence on such properties... 

Space limitations preclude more than an overview of these types aftertreated (post-treated), alternating, block, comb and graft, cross-linked, dendritic, hy-perbranched, hyper-cross-linked, star, and star-block. Comprehensive reviews of structure-based and source-based representations for them have been published (20,21). 

Postpolymerization reactions, such as grafting, cross-linking, acid and base hydrolysis, quatemization, amination, and pegylation, represent attractive alternatives to using... 

Similar ElFE-g-PSSA membranes were prepared by Arico et al. [93] with electron irradiation, subsequent grafting, cross-linking, and sulfonation. The obtained man-brane samples were of commercial size. The membranes showed good conductivity and low methanol crossover at a thickness of around 150 pm. MEA assembUes based on these manbranes showed DMFC performance and cell resistance values comparable to Nafion 117 (210 pm). Stable electrochemical performance was recorded during 1 month of cycled operation at a temperature of 110°C. 

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