Oxidative crosslinking

The initial drying of currently applied alkyd paints is accomplished by evaporation of solvent (physical drying). Subsequently, the eventual curing of the alkyd paint is completed by the formation of a polymer network, which is mainly formed by chemical crosslinks (oxidative drying) but in some cases also physical interactions between the fatty acid side chains occur, such as crystallization or proton-bridge formation [129]. Efficient network formation is crucial in the formation of dry films with good mechanical properties. Due to the presence of unsaturated units in the investigated LOFA- and TOFA-PHA bin-... 

Plasma vs. Corona Treatment of Polypropylene (PP1. Corona treatments of polyolefins to modify their surfaces are very common in the polymer industry. The chemistry at such surfaces has been widely studied by XPS (4). It is generally assumed that corona treatments create abundant amounts of radicals which react with oxygen to form a hydroperoxide. This reacts further to eventually form crosslinks, oxidized products (ranging from hydroxyls to esters) with and without chain scission. The latter process is believed to lead to low-molecular weight material. There is some controversy over this material. Its role in determining the surface properties of the modified polymer is not completely understood. Its formation cannot be demonstrated directly by XPS, but only by comparing spectra before and after washing. 

On the other hand, a slow controlled thermal oligomerization of nitrile groups, in air and at moderate temperatures, leads to highly conjugated, crosslinked, oxidized structures which make the fiber non-flammable and infusible. Such fibers are said to be stabilized. They can be further heat-treated in an inert atmosphere to form the carbon fibers (>99% carbon). 

Features Reactive produces liq. elastomers used alone or with solid elastomers in thermosetting and thermoplastic applies. features low vise., crosslinking, oxidation resist., good elec, props., ozone and UV resist. Properties Et. amber vise, liq. HC odor m.w. 6500 sol. in nonpolar soivs. sp.gr. 0.84 vise. 560,000 cps (60 C) flash pt. > 300 E iodine no. 19 dielec. str. 760 V/mll dielec. const. 2.20 (1 kHz) ethylene/propylene 48/ 52... 

Milicevic, D., Trifunovic, S., Popovic, M., VukaSinovic, T., Milic, Suljovrujic, E. The influence of orientation on the radiation-induced crosslinking/oxidative behavior of different PEs. Nucl. Instium. Meth. Phys. Res. B 260, 603-612 (2007)... 

Mechanisms of Crosslinking, Oxidative Degradation and Stabilization of UHMWPE... 

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