Are ziplock bags microwave safe?
Polyethylene ziplock bags are not recommended for microwave use as polythylene has a softening point of 95 C and a melting point of 105 which might be reached by steam coming off a food item. Polypropylene ziplocks can be used in the microwave as polypropylene has a higher melting point of 130 C which would not easily be reached by a microwave.