Variation of the parameters of inhibited oxidation of polyethylene in the region of phase transition

Abstract

Parameters of oxidation of polyethylene with molecular oxygen in the presence of a phenolic antioxidant, 2,2`-methylenebis(4-methyl-6-methylcyclohexylphenol), at 80 3210oC were studied. The possible mechanism of interaction of the polymer with the antioxidant near the melting point was considered theoretically. The suggested theoretical relationships are consistent with experimental data.

Change in the Properties of the Amorphous Part of Isotactic Polypropylene on Passing through the Melting Temperature

“…the melting temperature of the crystalline part of the polymer. A similar dependence for polyethylene is described well by Arrhenius's law with a break at the melting temperature [4].…”

Novel One-Step, in Situ Thermal Polymerization Fabrication of Robust Superhydrophobic Mesh for Efficient Oil/Water Separation

“…As shown in eq 6, the molecules of ROOH undergo rupture at the O–O bond comparatively readily with formation of free radicals, which in turn initiate new oxidation chains . Since considerable quantities of ROOH are accumulated, their decomposition and the formation of free radicals may proceed mainly by a bimolecular reaction between two ROOH molecules (eq 7) . It should be noted that alkyl, alkoxyl, and peroxyl radicals (R•, RO•, and RO 2 •) are highly reactive, and they are continuously generated and rapidly consumed in this process, thus making their concentration rapidly reach a stationary value .…”

“…63 Since considerable quantities of ROOH are accumulated, their decomposition and the formation of free radicals may proceed mainly by a bimolecular reaction between two ROOH molecules (eq 7). 64 It should be noted that alkyl, alkoxyl, and peroxyl radicals (R•, RO•, and RO 2 •) are highly reactive, and they are continuously generated and rapidly consumed in this process, thus making their concentration rapidly reach a stationary value. 65 Deducing from eqs (2−7), it could be concluded that the occurrence of degenerate chain branching reaction (eq 5) is the main reason for the formation of highly cross-linked polymer, and the interations between alkyl radicals (R•) and oxygen actually play the vital role.…”