Microwave safe fabric

[amythestcat.livejournal.com]

I will be making corn pillows to microwave for a heat pack. I have cotton muslin for the interior cover which should microwave just fine. For the removable outer cover I have some cotton poly broadcloth which I think should be just fine. I'm wondering if material like polar fleece should be alright? And by off chance, not likely, but acrylic safety eyes. Any place with a crafters list of microwave safe fabric and items that my net searches are not turning up?

Have a crafty week:) Thanks in advance.