I have found that using a poly-cotton blend is more difficult because they fray more and are slippery. I made this quilt from old Peanuts panels I had saved from the 1970s. This entire quilt was made from a poly-cotton blend and I had to deal with snags, with puckering, and had to use a lower iron setting. I tried various needles and threads, but I still was not completely happy with the outcome. I ended up using an all cotton backing. I, personally, like using 100% cotton and doubt I will tackle a mixed blend again (unless I make a crazy quilt someday.)
You can kind of see the seams puckering here...
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