Hello everyone, I'm looking to embed hollow nano plastic or ceramic spheres into an epoxy or polyurethane matrix. It is for my dissertation and I would like to carry out tests on the finished materials. Can anyone suggest any suitable resins that could be used as a matrix?

Any of the laminating resins will suit your purpose.  The challenge you may face is that the resins have their own properties.  You may not get a direct correlation between nanoparticle proportion with different resin types.   

I have in the past worked on clay-plastic nanocomposites in a university/research environment. The clay (silicate) was in the shape of sheets only a few atom layers thin and several hundred nanometers long and wide.The main problem we encountered and which we were able to overcome with suitable processing parameters was properly dispersing the nanomaterials in the polymer matrix, because these nanomaterials sure like to stick to each other. I remember some people in our research group were doing the same with epoxy resins, but don't have any details at this moment. Only thing I remember is big barrels of Araldite resins magically appearing in the labs donated I think by Ciba-Geigy (now Novartis).

What kind of nanomaterials are you planning to mix into the resins? Spheres are boring , it's the particles with higher aspect ratio like nanorods or nanoplatelets/sheets which will produce the sexier results.

If you have access to scientific literature databases through your school you can find shitloads of interesting papers with the right search words. There has been a lot research going on in the past 15 to 20 years.