The antonyms for the phrase "popped balloon" can be "inflated balloon," "unburst balloon," or "intact balloon." These words suggest the opposite of the original phrase, indicating that the balloon has not burst, but rather, is still inflated and whole. Such antonyms can be helpful when describing balloons in different states or conditions, and when one wants to suggest that a balloon is still usable or in good condition. For example, instead of saying "my balloon popped," one could say "my balloon is still inflated," providing a more positive spin on the situation.