Selecting the best silane coupling agent for pretreating conductive glass fiber

We have long engaged in selecting suitable silane coupling agent for pretreating conductive glass fiber (such fibers are widely used in stealth technology and electromagnetic shielding) so as to form the best possible chemical bond between the two. Now we go one step further, i.e., selecting the best among three very good silane coupling agents. The conductive glass fibers belong to the type of superior dielectric loss absorbent. The pretreatment is a key step in the preparation of this absorbent. We have developed a new pretreating method for initiating electroless plating on glass fibers based on palladium chemisorption on self-assembled monolayers (SAMs) of silane coupling agent. In several years of research, we discovered three good silane coupling agents; KH550 (γ-aminopropyltrietroxysilane), KH560 (γ-glycidoxypropyltrimethoxysilane), and Si602 (N-β-aminoethyl-γ-aminopropylmethyldimethyoxysil-ane). Experimental analysis with X-ray photoelectron spectroscopy (XPS) revealed that all three silane coupling agents have chemical bond interaction with the glass fiber's surface after treatment with silane coupling agent. The software of Guassian98 was used to analyze the theoretical model of the chemical bond between silane coupling agent and the surface of glass fibers; the theoretical chemical bond lengths are: 1.6569Å (KH550), 1.6736Å (KH560), and 1.6834Å (Si602). The photographs of scanning electron microscope (SEM) show that the silane coupling agent has an important effect on the coat's appearance. The coat of glass fibres, which are treated by KH550, possesses the best integrality and uniformity.