Exporting .mtl file

Hi,

I’m new to SketchUp. Can anyone assist me on how to export the following:
.obj file
.mtl file
I’m using SketchUp Pro 2014 (MAC)

Thank you!

SketchUp Pro includes an obj exporter, and there are extensions on both EW and SketchUcation that should work with Make. But I couldn’t find anything for .mtl files. I think these exporters embed materials rather than referencing a library?