The present invention provides a flowable material container assembly having a membrane tube disposed coaxially within a port tube. The membrane tube has an outer layer, a core layer, and an inner layer. The outer layer is a blend of a polyolefin and a thermoplastic elastomer. The core layer is a blend of a polyolefin and a thermoplastic elastomer. The inner layer is a blend of a polyolefin, a radio frequency susceptible polymer, and a thermoplastic elastomer.
