If you read the fine print and if you read between the lines, then yes it is wrong. Several places over the years have stated that you are not to use student loans for anything other than school purposes. I've seen it on the forms you sign, on handbooks for student loans, and even on income tax forms. I can't say exactly where (or if) it is printed on this year's forms because I haven't looked.
That said, no one will ever know or ask you about it. Thus, you are perfectly fine.
I'll leave the decision on ethics up to you. Is it ethical to temporarilly use taxpayer funds earmarked for other students who are in need for your own profit?