Hi M. -
I'm assuming that your daughter has only been in second grade for about a month or so, correct? If so, she's probably a bit overwhelmed with the kind of homework she's bringing home. Gone are the days when simple coloring and crafts were expected, as she gets older and the subjects get more advanced, homework is going to be more of a struggle for both of you.
Here's my suggestion...create a physical environment in your home where she can retreat to do her homework rather than feel banished or isolated by doing so. Maybe you can turn on some soft music (if it's not too distracting for her) and let her see that you're in the same room with her. Make sure that she's had a good snack before she begins, and check to see if she's physically comfortable where she's sitting. Turn the TV OFF when she's doing homework and sit with her for support ONLY when she needs it - don't watch over her to make sure she's doing her work. Maybe you can pull out a book and/or puzzle book yourself to do your "homework" at the same time. Kids her age don't want to miss out on anything, so if it appears that you're doing something more enjoyable and not including her, she may resent it and put up a fight to do any of her work.
If you feel that the subject matter is a problem, talk to her teacher about your concerns. Maybe he/she can recommend some supplemental books for you to read and some additional fun activities to make learning the particular subject more enjoyable for your daughter. I would also query some of the other moms in the class to see how they're fairing with homework time. As a last result, if your child continues this mutiny well into the year, I would seek professional help from companies such as Kaplan or Sylvan, but be aware that these institutions are very expensive and much of what you're paying them to do is to have time and patience with your child. At this grade level, nothing she's learning will be too difficult for you to help her with.
As a teacher for ten years, I can't stress enough how important it is to develop good, solid study habits as early as possible. Respecting and treating homework time as a haven for learning rather than a rigorous drag starts with you...because I'm sure your daughter is bright, she'll follow your lead.
Blessings to you and yours.