Deformation behavior and mechanical properties of hard elastic and porous films of polyethylene

Abstract

Hard elastic samples of linear polyethylene were prepared by melt extrusion at a high velocity of the melt flow and by subsequent annealing of crystallized samples. The deformation behavior of hard elastic samples obtained by annealing of as-spun samples at different temperatures has been analyzed at uniaxial extension resulting in formation of porous structure. Mechanical properties of microporous films in the longitudinal and transverse directions have been investigated. Composite systems consisting of a microporous polyethylene film and a thin layer of an electroconducting polymer have been prepared. Mechanical properties of composite systems, such as elastic modulus, tensile strength, and break elongation, have been compared with the properties of polyethylene substrates.

Novel Generation of Liquid Crystalline Photo‐Actuators Based on Stretched Porous Polyethylene Films

“…As a low‐cost polymer matrix we have used porous thin films of polyethylene (PE) developed at the Institute of Macromolecular Compounds (St‐Petersburg, Russia) under the supervision of Prof. G. Elyashevich 13–14. The porous films are characterized by very high specific surface areas (∼40 m 2 g −1 ), attributable to their strongly developed porous nature (in comparison, a dense non‐porous PE film has a value equal to 6.3 × 10 −4 m 2 g −1 ) and porosity (∼40–50%).…”

Composite membranes with conducting polymer microtubules as new electroactive and transport systems

“…The basic parameter at this stage is the spin draw ratio s . The sample structure involves a system of large folded-chain lamellae arranged parallel to each other and perpendicular to the orientation direction connected by tie chains statistically distributed over the lamellar surfaces [12,13].…”

Mechanoresponsive Hard Elastic Materials Based on Semicrystalline Polymers: From Preparation to Applied Properties

“…Typical hard elastic materials are known to demonstrate the advantageous combination of hard and elastic properties: high elastic modulus, high deformability, high strain recovery, and constant cross-section area and development of porosity upon deformation. ,− , Traditionally, HE polymers are used as precursors for the preparation of porous materials and the as-formed porous structure is usually stabilized by annealing to provide dimensional stability. After annealing, HE materials lose their elastic properties and become hard materials. ,, So far, the behavior of HE materials upon cyclic loading/unloading (or step cycle tests) has been addressed from a purely scientific viewpoint. We will demonstrate the advantages of EIC/SSR samples as hard elastic and “living” mechanoresponsive systems.…”

“…These strange materials have been given an oxymoronic name combining the perception from the strength of highly crystalline solids (“hard”) and rubberlike behavior of elastomers (“elastic”). Later attempts to replace this mixed metaphor with a more reasonable term “springy” , failed, and now the family of hard elastic polymers is marching worldwide and involves diverse semicrystalline polymers such as polyethylene, polypropylene and its blends, − polyoxymethylene, poly-3-methyl butene, poly-4-methyl pentene, polyethylene sulfide, polypivalolactone, poly­(vinylalcohol), and nylon 66. The most popular commercial hard elastic (HE) polymers are produced under the Celgard trademark (the Celanese Corporation) and, from the start, Celgard membranes have been used as key components in blood oxygenation devices.…”