This has to do with Polymer Chemistry 
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Every Brand of filament is a carefully created blend of plastics and additives that is a proprietary secret. Things to improve flow, others to improve strength, you get it. Switch Brands and you get different settings needed.
There are interactions - something that makes it stronger may make it stringy or need a lower temp. Same with the color additives. Personally, I’ve noticed Reds, Yellows, and Blacks generally run differently than the others in their group.
Get it? 