unmixable

/ʌnˈmɪksəbəl/
adjective
  1. Not able to be mixed together; describing substances that do not blend or combine.
    • The two powders were unmixable, so the recipe failed.
    • Some liquids are unmixable even when you shake them vigorously.
    • Oil and water are unmixable because of their different chemical properties.
  2. Describing people, ideas, or groups that cannot be combined or made to work together harmoniously.
    • The two political philosophies seemed unmixable in the debate.
    • Their personalities were unmixable, leading to constant arguments.
    • In the office, the teams were unmixable due to old rivalries.