My bad !. In the world of Web, there does exist dark web, deep web and surface web.
Coming to the polymers, if we go by general definition of words 'web' and 'surface', if polymer web is an object or body, then 'surface' would be the outer or upper or front layer of the polymer web or body.
I would not know, however, if Web and Surface are used interchangeably in your field of study.
Hope this is of help!