PBT Meltblown Description Johns Manville’s Dynaweb meltblown media is available in both PP and PBT. We have the capability of supplying a polymer suitable for your application. Both types of media are produced from the finest grades of high purity polymers and meet the following requirements: FDA Title 21 CFR 177.1520 Title 21 CFR 177.170 USP XXII Class VI Systemic Toxicity Test Intracutaneous Reactivity Test Muscle Implantation Test Macroscopically Both polymers are available as calendered and uncalendered.