I've combined some primitives into a new Prop.  I am saving as an OBJ but unfortunately I am ending up with all the mat goups originally assigned to the primitive props.
Is there a program or way to DELETE unwanted MATERIALS from an OBJ?  I've tried editing the MTLs out of the obj but it corrupts the file.  It would be nice if you could do this in BLENDER. Maybe you can. But I am not sure how.

Thoughts?

Windows 10 - Poser Pro 2012 - 64Bit - 24GB RAM - 4 x 3.40 GHZ processor