The substance is used in space for the construction of temporary habitats. I suppose this is plausible if you manage to find a large source of ice and bring it into a stable orbit. It won't melt into liquid, and perhaps the reinforcing fibers could help prevent sublimation.
A lot of the novel strained my ability to suspend disbelief, but the overall scope and ambition is so awesome I was able to forgive the poor editing. It's attempting to be hard sci-fi, much of the novel is taken up by technical descriptions that could only appeal to an engineer-minded person.
While the 2nd half of the book is definitely still sci-fi territory, the first part is slowly getting into the plausible tech realm, 12 years after the book was written. We now have a much stronger space industry, and probably could match or exceed the payload to orbit in 2 years from the book (if everyone would work towards the same goal, which is still a bit of fantasy but hey...)
Mainly I remember skimming the middle third because it felt like such a drag.
Except bringing an asteroid all the way down to the ISS. That part was uncharacteristically thoughtless, I think.