Photosil™

The Photosil™ process is a surface modification technology which substantially alters the surface structure and chemistry of a polymer. Originally developed to protect polymer materials used in space exploration, Photosil™ is an innovative process with many terrestrial applications protecting polymer materials in a wide range of environments. The process alters a range of surface related properties including: resistance to oxidation and atomic oxygen erosion, wettability, adhesion, and permeability of gases and liquids. The versatile Photosil™ process can be adapted to meet these properties. The Photosil™ process incorporates silicon-containing groups into the sub-surface layer (i.e. up to 1 µm in depth) of the polymer structure. Such silicon surface modification produces the unique properties which differentiate the Photosil™ process.

The Photosil™ process is able to effectively modify a wide variety of polymer and composite materials. These materials range from polyethylene to complex polyimides. The Photosil™ process produces a uniformly graded layer, not a coating. Unlike a coating, the graded layer lacks an abrupt transition boundary and thereby resists cracking and spalling caused by thermal stress, physical stress, and even corrosion. Under certain circumstances, the modified surface structure also has a unique self-healing capability. A key advantage of the Photosil™ process is that, unlike other surface treatments, only a thin layer near the surface is modified, resulting in little or no change to the bulk material properties of the surface material.

Untreated Lacing Cord	Photosil™ Treated Lacing Cord
Aromatic polyamide (Nomex®) fiber flat braided lacing cord impregnated with a synthetic resin, suitable for spacecraft wire assemblies, was treated by the Photosil™ process. The accelerated AO ground-simulation revealed the untreated plasma-exposed lace shows the typical highly eroded, "cone-like" surface texture and the development of surface pores; in contrast, the Photosil™-treated lacing shows no change in surface morphology.