Most comic boards are acid free on only one side - and the magazine would be placed against that side when placed in a bag.
I have my fabric on magazine boards. They're just like comic boards but are 8.5 x 11 and fit my selves better, plus yardage folded twice fits perfectly as most is 42 to 44" wide. For amounts over 3 yards, I use two boards and they are more stable. I used pins but should probably switch to the plastic coated paper clips.
One thing I did as I folded my stash on the boards was to include a strip of paper. On it is the width and length, the manufacturer and collection/pattern # as well as whether it was washed. I figure it will make it easier to determine if a piece will meet my needs without having to unwrap and measure.