Unable to post from bootstrap modal - node.js

Question

In the header of my app, I have a link, clicking on which opens up the bootstrap popup modal. When I insert data in the text boxes and click on Submit, No action is happening. Please advice. Thanks.
Here is my html for the modal:
<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h4 class="modal-title">Modal title</h4>
</div>
<form action="addCard" method="post" id="addcard" class="form-horizontal" role="form">
<div class="modal-body" style="height: 140px;">
<div class="form-group" style="height: 30px;">
<label for="title" class="col-md-3 control-label">Title</label>
<div class="col-md-9">
<input type="text" class="form-control" name="title" placeholder="Enter Card title here...">
</div>
</div>
<div class="form-group" style="height: 30px;">
<label for="title" class="col-md-3 control-label">Description</label>
<div class="col-md-9">
<input type="text" class="form-control" name="desc" placeholder="Enter Card description here...">
</div>
</div>
<div class="form-group">
<label for="priority" class="col-md-3 control-label">Priority</label>
<div class="col-md-9">
<select name="priority" class="form-control">
<option value="critical">Critical</option>
<option value="high">High</option>
<option value="normal">Normal</option>
<option value="low">Low</option>
</select>
</div>
</div>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
<button type="button" class="btn btn-primary" type="submit">Submit</button>
</div>
</form>
</div><!-- /.modal-content -->
</div><!-- /.modal-dialog -->
</div><!-- /.modal -->
I have this line in my app.js file:
app.post('/addCard', routes.addCard);
Index.js:
exports.addCard = function (req,res)
{
res.render('index');
}