Abstract: Improved packaging films which can be heat sealed and then easily opened when desired are provided. The heat sealable packaging films are prepared from ionomers, acid copolymers, or mixtures thereof which are modified with polypropylene, ethylene vinyl acetate copolymer, and, optionally, polyethylene. The resulting films are heat sealable with a relatively low heat seal initiation temperature and with consistent seal strengths over a relatively broad heat sealing temperature range. The heat seal strength, which is retained over time, can be varied or adjusted to desired values by adjusting the composition of the modified ionomer blend. The seal can be opened in a clean manner (i.e., not stringy). Since the seal whitens upon opening, the film of this invention allows for tamper evident packaging.