Please look up Robert Scholes and Nancy Comley, "The Practice of Writing." Persuasion and argumentation are different. The primary purpose of persuasion is to move an audience to some sort of action. The primary purpose of argument is to present/explore the truth.
It is common in persuasion to present "facts," that aren't facts, "research," that isn't research. See many commercials.
It is common in argument to do actual research, the purpose of which is not merely to either a) confirm what you already thought, or b) talk your aaudience into doing something, but c) explore reality.
I am sorry, but you're incorrect. "Research/persuasive," is a contradiction in terms to some extent at least.
On the other hand, there's Churchill's crack about needing to protect the truth with "a bodyguard of lies." And there's the way that argument in the college sense usually suggests that action is left up to the reader. Then we turn around, and wonder why decent people find college professors exasperating...
Thanks for the discussion.