Elastomeric materials are notoriously difficult to adhesively bond to themselves or to other materials. One of the reasons for this is the labile nature of their polymer chains, an inherent property instrumental in the material’s elastic nature. However plasma can help promote the adhesive properties of elastomers in a number of ways. For example plasma can clean mold release agents, volatile hydrocarbons and other contaminating species from the substrates that will interfere with a bond. Oxidizing plasmas are used to add oxygen groups to surface. This increases polarity and renders them hydrophilic, or wettable to adhesives. Surface topography can be selectively altered in a plasma environment, either by the bombarding effect of ions accelerated towards the surface, or by a chemical etch process. Roughened surfaces have higher surface areas, equating to a higher number of binding sites thus improving bonding.
