Membranes:

• EPDM
• Silicon
• TPU
• NBR
• PTFE- EPDM

We manufacture our disc diffusers with compression molded membranes. Standard materials are EPDM and fluoroelastomer layered EPDM. Compression molding ensures that we produce a part with even specific gravity and uniform tear resistance. Other molding techniques such as injection molding produce similar looking parts, but the tear resistance of a compression molded part ismultidirectional, whereas the tear resistance of an injection molded part tends to be unidirectional just like wood which has a grain. There is an art to using just the right amount of plasticizer in an EPDM membrane. Use too much, or the wrong type, and emulsifying fats can leech plasticizer and cause shrinkage and increase hardness. Use too little, and the rubber loses its memory, bubble size increases, and the membrane is at risk for flexure failure. E.M. has had a great deal of experience experimenting with different types and amounts of plasticizer, as well as other components of formulated EPDM rubber, such as fillers and curatives, and we put this experience to work. Membrane perforation and surface charge are additional considerations. E.M. perforates disc membranes from the inside out with specially shaped knives. This results in the smallest part of the perforation on the membrane surface where the bubble is released. Through proprietary compounding and surface treatments, we are able to create a smooth perforation on a hydrophilic surface which quickly releases small bubbles, typically from 1 to 2 mm in diameter. E.M. uses environmentally friendly materials whenever possible. Our disc diffuser parts are predominantly made of polypropylene, which offers the added benefit of high temperature resistance to 212 F (100C)