Study of adhesion and surface properties of low‐density poly(ethylene) pre‐treated by cold discharge plasma

Abstract

The low-density poly(ethylene), which is prone to hydrophilicity, dyeability, and bondability, was modified by surface barrier discharge and radio-frequency discharge plasma. A process of plasma modification was investigated to improve adhesion between poly(ethylene) and more polar polymers, to improve surface properties, and to form a new surface containing polar functional groups incoming to reactions with diazo-compounds, and/or vinyl silanes. The measurements of contact angles and peel strengths of adhesive joints were carried out for characterization of the surface and adhesive properties of the polymer modified by plasma. The topography of modified poly(ethylene) was studied using atomic force microscopy, and changes in chemical structure were analyzed with X-ray photoelectron spectroscopy.

Improving mechanical performance of thermoplastic adhesion joints by atmospheric plasma

“…[3]. As polyethylene is characterized by a marked hydrophobic behavior resulting from its non-polar nature together with very smooth surfaces, it is necessary in many cases to carry out a previous surface treatment to promote the appropriate changes (mainly chemical and surface topography changes) in order to increase surface activity thus enhancing anchorage processes typical of paints, coatings and adhesion joints [4][5][6].…”

Effect of cold atmospheric plasma treatment on hydrophilic properties of fluorosilicone rubber

“…The so‐called plasma modification refers to the etching, oxidation, and cross‐linking reactions between the material's surface and electrons, positive ions, negative ions, free radicals, atoms, and molecules, those generated from electronic discharge, to change the surface properties . Meanwhile, the treatment has no by‐effect on the physics and mechanical properties of the treated substance . Its modification effect depends on the processing atmosphere, processing time, power, and discharge pressure .…”

Use of atmospheric plasma treatment to improve adhesion properties of sodium ionomer sheets

“…This is more efficient than chemical processes; it is faster and environmentally friendly [15][16][17][18]. The highly active species in the plasma gas promote chain scission and subsequent free radical formation which is responsible for two different main effects: on the one hand low molecular weight oxidized material (LMWOM) resulting from reaction of some free radicals and air promote changes in surface topography [6,7,19,20]; on the other hand free radicals on the surface tend to react with the oxygen which is present in both air plasma and subsequent exposure of plasma-treated materials to air. [20,21].…”

“…to promote some chemical reactions that, in general terms, lead to surface abrasion and insertion of different functionalities. In many cases it is necessary the total immersion of the polymer part to be successfully treated in a chemical bath which contains the appropriate chemical agents to produce superficial activation [6][7][8][9]. The major drawback of using these chemical processes is the aqueous waste which may contain potentially contaminating chemical components [10][11][12].…”