Polymer plugging service

Pressure Relief Valve for Polymer Plugging Service... 

Application Systems where high capacity near-design rates to be maintained in continuous service. Handles suspended crystal and small solid materials, as well as polymer forming materials. Holes become plugged in salting-out systems where trays run hot and dry (as underside of bottom tray). Good in vacuum or low-pressure-drop design. 

What is true for the container in the container-closure system is equally true for the closure alone and, essentially, for the elastomeric stoppers, generally butyl rubber, which cap the vial. Fran DeGrazio from West Pharmaceutical Services has done a lot of research in this field and studied many alternatives to their formulation trying to keep down the extractables (essentially volatile) and leachables and prevent adsorption of oils, waxes, polymers, and others on the freeze-dried plug. 

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