Surface Functionalization of Silicone Rubber for Permanent Adhesion Improvement

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Jan Roth - , Leibniz Institute of Polymer Research Dresden (Author)
  • Victoria Albrecht - , Leibniz Institute of Polymer Research Dresden (Author)
  • Mirko Nitschke - , Leibniz Institute of Polymer Research Dresden (Author)
  • Cornelia Bellmann - , Leibniz Institute of Polymer Research Dresden (Author)
  • Frank Simon - , Leibniz Institute of Polymer Research Dresden (Author)
  • Stefan Zschoche - , Leibniz Institute of Polymer Research Dresden (Author)
  • Stefan Michel - , Leibniz Institute of Polymer Research Dresden (Author)
  • Claudia Luhmann - (Author)
  • Karina Grundke - , Leibniz Institute of Polymer Research Dresden (Author)
  • Brigitte Voit - , Leibniz Institute of Polymer Research Dresden (Author)

Abstract

The surface properties of poly(dimethyl siloxane) (PDMS) layers screen printed onto silicon wafers were studied after oxygen and ammonia plasma treatments and subsequent grafting of poly(ethylene-alt-maleic anhydride) (PEMA) using X-ray photoelectron spectroscopy (XPS), roughness analysis, and contact angle and electrokinetic measurements. In the case of oxygen-plasma-treated PDMS, a hydrophilic, brittle, silica-like surface layer containing reactive silanol groups was obtained. These surfaces indicate a strong tendency for "hydrophobic recovery" due to the surface segregation of low-molecular-weight PDMS species. The ammonia plasma treatment of PDMS resulted in the generation of amino-functional surface groups and the formation of a weak boundary layer that could be washed off by,polar liquids. To avoid the loss of the plasma modification effect and to achieve stabilization of the mechanically instable, functionalized PDMS top layer, PEMA was subsequently grafted directly or after using gamma-APS as a coupling agent on the plasma-activated PDMS surfaces. In this way, long-time stable surface functionalization of PDMS was obtained. The reactivity of the PEMA-coated PDMS surface caused by the availability of anhydride groups could be controlled by the number of amino functional surface groups of the PDMS surface necessary for the covalent binding of PEMA. The higher the number of amino functional surface groups available for the grafting-to procedure, the lower the hydrophilicity and hence the lower the reactivity of the PEMA-coated PDMS surface. Additionally, pull-off tests were applied to estimate the effect of surface modification on the adhesion between the silicone rubber and an epoxy resin.

Details

Original languageEnglish
Pages (from-to)12603-12611
Number of pages9
JournalLangmuir
Volume24
Issue number21
Publication statusPublished - 4 Nov 2008
Peer-reviewedYes
Externally publishedYes

External IDs

PubMed 18828614
Scopus 56449092390
ORCID /0000-0002-4531-691X/work/148607771

Keywords

Keywords

  • Hydrophobic recovery, Neutron reflectometry, Plasma treatment, Poly(dimethylsiloxane), Polydimethylsiloxane, Exposure, Polymer, Films