Elastomers
DiaCom has developed an extensive inventory of rubber compound formulations to meet the demands of a wide range of rolling diaphragm applications and maintains a full time Rubber Chemist on-staff, constantly working to develop rubber formulations to meet the demands of an ever-changing industry.

DiaCom works with all types of rubber materials, such as, Nitrile, EPDM, Neoprene, Fluorosilicone, Silicone, SBR, Fluoroealstomers, (Viton®), Hydrin and Vamac®. Specialty compounds have been developed that include FDA grade, NSF capable, UL-157 approved for use in propane, and chloramine resistant compounds.

Rubber has a variety of physical properties, such as, tensil strength, elongation, modulus, compression set, and tear resistance, as well as, chemical compatiblity. All of these preoperties must be considered when selecting a bubber to be used in a rolling diaphragm. Contact a DiaCom representative for proper rubber selection.

Chemical Compatibility Table

Butyl Ethylene
Propylene		 Fluoro-
Carbon		 Fluoro-
Silicone		 Hydrin Neoprene Nitrile Silicone Styrene
Butadyene

IIR EPDM FKM FVMQ CO/ECO CR NBR VQM SBR


Physical Properties
Compression Set Resistance Good Fair Good-Excel Fair-Good Fair-Good Fair-Good Good Good-Excel Good
Durometer Range (Shore A) 30-100 30-90 50-95 35-80 30-95 40-95 20-90 25-90 40-100
Elongation % 300-800 200-800 100-450 100-500 300-400 650-850 400-600 90-900 400-500
Tensile Strength (PSI) 2,000+ 1,500-3,000 1,500-3,000 350-850 1,500-2,000 2,000-3,000 1,000-3,500 600-1,500 2,000+
Nitrogen Permeability Resistance Excellent Good Excellent Poor Excellent Fair Good Poor Fair
Resilience Excellent Good Fair Good Good Excellent Good Poor-Excel Good

Mechanical Resistance Properites
Abrasion Good Good Good Fair Fair-Good Good Excellent Poor-Excel Excellent
Electrical Properties- Insulating Good Excellent Fair Excellent Poor-Fair Fair Fair Excellent Excellent
Electrical Properties- Conductive Fair Poor Excellent Poor Excellent Fair Fair Poor Poor
Impact Good Good Poor-Good Fair Good Good Fair Poor-Good Excellent
Tear Good Poor Poor-Good Fair Good Good Good Poor-Good Fair

Temperature Resistance Properties
Cold Temperature Flexibility Good Good Fair-Good Good Good Fair Good Excellent Good
Flame Retardance Poor Poor-Fair Excellent Outstanding Fair Good Poor-Fair Fair-Poor Poor
Heat Aging Good Excellent Outstanding Outstanding Excellent Good Good Excellent Good

Environmental Resistance Properites
Ozone Good Excellent Outstanding Outstanding Excellent Excellent Poor Excellent Good
Radiation Fair-Good Poor Fair-Good Good-Excel Fair Fair-Good Fair-Good Fair-Excel Good
Weather Excellent Excellent Excellent Outstanding Good Excellent Good Excellent Fair

Chemical Resistance Properties
Acid- Dilute Concentration Fair Good-Exel Fair-Good Good-Excel Fair-Good Good-Exel Fair-Good Fair-Good Fair-Good
Aliphatic Hydrocarbons Poor Poor Excellent Excellent Excellent Good Excellent Poor-Fair Poor
Alkai-Dilute Concentration Fair-Good Good-Exel Good-Exel Good-Exel Fair-Good Good-Exel Good-Exel Good-Exel Fair-Good
Aromatic Hydrocarbons Poor Poor Excellent Good-Exel Excellent Fair Fair-Good Poor Poor
ATF Type A Poor Poor Excellent Excellent Good Good Excellent Good Poor
Chlorinated Hydrocarbons Poor Poor Excellent Good-Exel Good-Exel Poor Fair-Good Poor Poor
Diesel Oil Poor Poor Excellent Good Excellent Fair Good-Exel Poor Poor
Diester Lubricants Poor Poor Excellent Excellent Good Poor Fair-Good Poor Poor
EP Lubicants Poor Poor Excellent Excellent Poor Poor-Fair Fair Good Poor
Ethyl Alcohol Fair Good-Exel Excellent Excellent Good Excellent Good Excellent Fair
Ethlene Glycol Excellent Excellent Excellent Excellent Excellent Excellent Excellent Excellent Good
Ethylene Glycol/Water Fair-Good Good Good Good Fair Good Good Excellent Good
Gasoline Poor Poor Excellent Excellent Good-Exel Fair Good-Exel Poor Poor
Hydraulic Fluids- Petroleum Base Poor Poor Excellent Excellent Excellent Poor-Fair Fair-Good Poor Poor
Hydraulic Fluids-Silcate Ester Fair Poor Excellent Outstanding Fair-Good Good Good Poor Poor-Fair
Hydraulic Fluids-Phosphate Ester Good Good Poor Poor Poor Fair Poor Good Poor
Keytones Good Fair-Excel Poor Poor Fair Fair Poor Fair-Good Good
Lubicating Oils- High Aniline Fair Poor Excellent Excellent Excellent Good Good-Exel Good Poor
Lubicating Oils-Low Aniline Good Poor Excellent Excellent Excellent Fair Fair-Excel Poor-Fair Poor
Silicone Oil Good Excellent Excellent Excellent Excellent Excellent Good Poor Good
Steam - Above 121°C (250°F) Poor-Fair Excellent Fair Poor-Fair Poor Fair Fair Poor-Fair Poor-Fair
Water- 100°C (212°F) Good Excellent Excellent Excellent Good Good Excellent Excellent Excellent