硅烷偶联剂在导电玻璃纤维制备中的应用

Selecting the Best Silane Coupling Agent for Pretreating Conductive Glass Fiber

导电玻璃纤维是性能优良的电损耗型吸收剂,前处理是利用化学镀方法制备该材料的关键步骤。文中提出了一种用硅烷偶联剂对玻璃纤维进行前处理,基于分子自组装膜(SAM s)吸附胶体钯颗粒的方法,成功地引发了在玻璃纤维表面的化学镀。研究了几种不同结构的硅烷偶联剂对玻璃纤维表面的修饰改性。XPS分析表明,经过偶联处理后,不同结构的硅烷偶联剂都和玻璃纤维表面的硅发生了化学键合作用。论文首次利用G aussian98软件对不同结构硅烷偶联剂和玻璃纤维表面发生作用的理论模型进行了分析。计算结果表明,不同结构的硅烷偶联剂和玻璃纤维表面发生的化学键合作用力存在着明显差异,KH 550与玻璃纤维表面硅的结合力要强于KH 560和S i602。SEM分析进一步表明,硅烷偶联剂对导电玻璃纤维的镀层形貌有着重要的影响,KH 550处理后的玻璃纤维,其镀层的完整性和均匀性更好。该诱发化学镀的方法具有镀层厚度均匀、附着力强的优点。

Aim. 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 ehemisorption 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-glyeidoxypropyltrimethoxysilane）, and Si602 （N-β-aminoethyl-γ-aminopropylmethyldimethyoxysilane）. Experimental analysis with X-ray photoelectron spectroscopy （XPS） revealed that all three silane eoupling agents have chemical bond interaction with the glass fiber＇s surface after treatment with silane eoupling agent. The software of Guassian98 was used to analyze the theoretical model of the ehemical bond between silane coupling agent and the surface of glass fibers; the theoretical chemical bond lengths are： 1. 656 9A （KH550）, 1. 673 6A （KH560）, and 1. 683 4A （Si602）. The photographs of scanning electron microscope （SEM）, shown in Fig. 6 in the full paper, 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.