My business partner and I are in the process of starting up a new business?

we have took all the necessary steps and research to start. However the problem is financing, we will need 50k for startup but dont have it in liquid ets. Also we both have credit issues we are taking care of and this is making it hard to start the business. We have a Dun and Bradstreet number.can we apply for credit for the business with this number and not use our social. Also I was wondering if we are LLC should we be using our own social since I thought the purpose of LLC was to protect yourself and ets.