If you wake up with knotty, frizzy hair, your pillowcase might be the culprit....

https://www.apu-bookmarks.win/wake-up-with-less-frizz-by-tweaking-your-sleep-setup-cotton-causes-friction

If you wake up with knotty, frizzy hair, your pillowcase might be the culprit. Standard cotton creates friction that snags delicate strands overnight