George Edward Ealer

Flexomer™ Polyolefins-a Unique Class of Ethylene Copolymers for Low Temperature Film Applications

FLEXOMERTM polyolefins, referred to as very low density poly ethylenes (VLDPEs), are manufactured by a gas-phase, fluid bed process tech nology. Commercially available products typically range in density from 0.880 to 0.912 g/cc. The growing family of VLDPEs includes both narrow and broad molecular weight distribution polymers. The low crystallinity of these resins results in energy absorbing characteristics that yield outstanding low tempera ture impact properties. The lower brittleness temperature of VLPDE products provides superior low temperature performance when compared with ethylene vinyl acetate (EVA) and linear low-density polyethylene (LLDPE) copolymers.

Flexomer Resins-Another Class of Polyolefins for Film Extrusion:

Flexome™ resins represent a new family of polyolefins which exhibit a combination of properties heretofore unavailable. The properties of these resins and some of their blends are given and then compared to more es tablished resins such as linear low density polyethylene (LLDPE), a high pressure produced low density polyethylene (LDPE) and ethylene vinyl acetate copolymers (EVA). It is shown that a good balance of overall toughness, tensile strength and low temperature properties can be obtained, especially when copolymers with high-alpha olefins (HAO) are employed. Selected film fabrica tion effects are reviewed and certain end-uses are suggested based on the prop erty balance obtained with these resins.

Characterization of surface-treated polyethylene for water-based ink printability

With increasingly stringent EPA guidelines for controlling emissions of volatile organic compounds on the horizon, the desirability to move to water-based printing inks is evident This paper examines the effects of corona discharge treat ments which are commonly used to improve ink adhesion to polvethylene. Electron spectroscopy for chemical analysis (ESCA) was used to determine the surface chemi cal changes induced by corona treatments in pure polyethylene extruded films and in formulated resin systems This data was correlated with surface tension and ink adhesion measurements to show the effects of treatment and additives on the final printability of the films with particular emphasis on water-based inks. In addition, the effects of stonng treated film prior to printing and of retreating these films were also examined The results of these tests have shown that formulated linear low den sity polyethylene (LLDPE) films treat and print at least as easily as high-pressure low-density polyethylene (HP-LDPE) counterparts.