One issue would be if the circular saw blade is "universal" or "cross" cut and you are mainly going to "rip" cut on the table saw. This may not produce the best finish or be as quick. As circular saws often rip cut themselves there may not be any problem.
The other issue is whether the hole in the middle of the blade is the right size for your table saw, if not and you haven't got a spacer the blade would be unbalanced and probably dangerous.
i thought that circular saws use a neg rake blade and table saws use a pos rake blade and if you put a circular saw blade on a table saw it could be dangerous as it has a tendency to try and self feed your wood.