What's the noun for incompatible? Here's the word you're looking for.
incompatible
(medicine) An incompatible substance; one of a group of things that cannot be placed or used together because of a change of chemicalcomposition or opposing medicinal qualities.
“Their constant arguing and different viewpoints on important issues highlighted the incompatibility between the two colleagues, making it impossible for them to work as a team.”
“Their fundamental values and beliefs were a constant source of incompatibility, causing endless arguments and a deep sense of discord in their relationship.”
“We examined the genetics of hybrid incompatibility between two closely related diploid hermaphroditic plant species.”
“Griffin argues that incompossibility is necessary and extrinsically grounded in the essential attributes of God since God cannot actualize incompossible substances.”
“Incompossibility, it will be seen, is only incompatibility let loose.”