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Obtaining and properties of polyolefin composites metamaterials with copper micro- and nanoflakes

Łoś P., Łukomska A., Kowalska S., Jeziórska R., Krupka J.

Polimery

2011

T. 56, nr 4

324-327

In the paper a novel preparation method of polyolefin composites of metamaterial properties is presented. The studied composites were obtained by melt mixing of polyolefins and copper flakes of micrometer and/or nanometer-size, as conducting inclusions. The precise control of thickness and structure of the copper layer was achieved by the application of the current pulse and reversed current pulse electrolysis. The structure of the deposited layer on a stainless steel plate and size of copper flakes in polymer composites were studied using a scanning electron microscope (SEM). The electromagnetic properties of prepared metamaterials were measured by split dielectric resonator methods.

W artykule przedstawiono nową metodę otrzymywania kompozytów poliolefinowych o właściwościach metamateriałów. Kompozyty wytwarzano metodą mieszania w stanie stopionym poliolefin oraz mikro- i nanopłatków miedzi za pomocą mieszalnika typu PlastiCorder firmy Brabender. Płatki miedzi o wymiarach mikro/nanometrycznych otrzymywano usuwając mechanicznie z płytki stalowej warstwę miedzi osadzoną tam podczas procesu pulsowej elektrolizy prądowej ze zmianą kierunku prądu. Do badań struktury osadzonej warstwy miedzi jak i wymiarów płatków miedzi w matrycy polimerowej użyto skaningowego mikroskopu elektronowego (SEM) (rys. 1 i 2). Właściwości elektromagnetyczne otrzymanych metamateriałów badano za pomocą metody rezonatorów dielektrycznych (tabela 1).

Metamaterials based on polymer dispersions of nanoparticles and particles of copper obtained by cathodic current pulse electrolysis

Łoś P., Łukomska A., Kowalska S., Jeziórska R., Zaprzalski P., Krupka J.

Materials Science Poland

2011

Vol. 29, No. 1

35--40

In the present paper a novel group of electromagnetic metamaterials as well as the method of their fabrication is presented. The studied metamaterials are polymer composites and nanocomposites made of polymer matrix/host (ethylene-vinyl acetate (EVA), polyethylene, polypropylene etc.) filled with copper flakes, of micrometer and/or nanometer size, as the conducting inclusions. The copper filler flakes were obtained by cathodic current pulse electrolysis from copper sulfate electrolytes at the stainless steel electrodes. SEM analysis showed that the morphology and structure of the copper deposit can be precisely controlled by applying different kind of current pulse and reversed current pulsed electrolysis. The polymer composite metamaterials formed by extrusion of small beads of polymer mixed with the copper flakes consisted of polymer matrix and copper flakes, ranging in length from 1 to 500 micrometers, and ranging in thickness from 80 nm to 2000 nm. The concentration of the copper flakes ranged from 0.5 wt% to 40 wt%, depending on the applications and required electromagnetic and mechanical properties. The studied materials were found to exhibit effective magnetic permeability that was smaller than unity, which is indicative of the typical properties of metamaterials. Present development solves technological and economical problems related to modern microelectronics methods which are currently mainly used for metamaterial fabrication.