Influence of crosslinking on crystallization, rheological, and mechanical behaviors of high density polyethylene/ethylene‐vinyl acetate copolymer blends

Abstract

High density polyethylene (HDPE)/ethylene-vinyl acetate copolymer (EVA) blends with selective crosslinking the EVA phase were prepared and the crystallization, rheological, and mechanical behaviors were studied. Selective crosslinking of EVA component could greatly improve both tensile and impact strengths of the HDPE-rich blends and influence melting enthalpy at different annealing temperature in successive self-nucleation and annealing procedure. Dynamic mechanical analysis reveals that glass transition temperatures of both the HDPE and EVA components are lowered upon blending and are raised upon crosslinking. The uncrosslinked HDPE/EVA blends are unstable in the melt and show increment in storage modulus (G 0 ) and decay in loss tangent (tand) with annealing time associated with phase coarsening. However, morphology of selectively crosslinked blends in the melt state is highly unstable, characterized by a fast migration of uncrosslinked HDPE component out of the crosslinked EVA phase to the surface resulting in a rapid decay in G 0 and an increment in tand at the early stage of annealing. POLYM. ENG. SCI., 54:2848-2858

Influence of Hydrolyzed Polyacrylamide Hydrogel Stiffness on Podocyte Morphology, Phenotype, and Mechanical Properties

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Technological characterization of PE/EVA blends for foam injection molding

“…They used differential scanning calorimetry (DSC) analysis which provides more information on the phenomena involved during foaming in order to control and optimize the processing conditions. Zhang et al [7] studied the crystallization, rheological, and mechanical behavior of HDPE/EVA blends with selective cross-linking in the EVA phase. The rheological measurements and microscopic observations reveal that the non-cross-linked blends are more stable than the cross-linked blends.…”

Preparation and properties of ethylene-vinyl acetate grafted acrylonitrile

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