Branching, polyethylene

Chain Free radical Polybutadiene Polyethylene (branched) Polyisoprene Polymethylmethacrylate Polyvinyl acetate Polystyrene... 

In initiation of oxidation, the important role may also be played by reactive bonds in a polymer. With polyethylene which is the most simple structurally, such reactive sites may be small concentrations of double bonds or more numerous sites of branching of a main chain to side alkyls. Investigation of the oxidation reaction of different types of polyethylene has. however, revealed that the degree of polyethylene branching from 0 to 20 branches for each 1000 carbon atoms of the main chain does not affect the induction period of oxidation [13]. 

Michalak A, Ziegler T, Polymerization of ethylene catalyzed by a Nickel(+2) anilinotropone-based catalyst DFT and stochastic studies on the elementary reactions and the mechanism of polyethylene branching, Organometallics, 22, 2069-2079 (2003)... 

Phase diagrams have been proposed for blends of polyethylenes where the first component is linear, or less branched, and the second component is more branched. The method involves quench cooling each blend composition from the melt at various temperatures, so that there is insufficient time for liquid-liquid phase separation. Separated blends are considered to be separated at the particular temperature of the melt prior to quenching. TEM and DSC are used to characterize the quenched blends. The phase diagrams exhibit UCST behavior, depending on the difference in branching content of the component polyethylenes. Branch length has been found not to be important since it is the branch points that are excluded from the crystals (20,21). 

PMMA PC (polyethylene terephthalateglycol) High- viscosity PETG PE (polyethylene), branched homopolymer Polyimide Styrene copolymer Silicone... 

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