by VIP Rubber & Plastic VIP Rubber & Plastic No Comments

Silicone vs. Neoprene Rubber in Defense and Aerospace

What you need to know about silicone vs. Neoprene rubber for demanding applications.

Silicone and polychloroprene (also known as Neoprene) rubber resist ozone, oxygen, water and weather. They’re supplied as Silicone Sheet Rubbersheets and extrusions, which often are fabricated into seals, and are also molded into parts. These synthetic elastomers have many similar properties, but silicone and Neoprene rubber also have one important difference. Silicone has a broader temperature resistance which allows it to seal and insulate against extreme heat while remaining flexible at colder temperatures.

By understanding the comparative advantages and disadvantages of each type of elastomer, engineers can make the right choice during compound selection. Yet it’s also critical to consider material costs and availability. In addition to environmental and chemical resistance, buyers may need custom compounding and shorter lead times. Commodity rubber is fine for some applications, but aerospace and defense may need grades that meet specifications such as A-A-59588.

Environmental and Chemical Resistance

Silicone supports a wider range of temperatures and has better compression set, but Neoprene offers higher abrasion resistance and tensile strength. The table below describes some common material properties for each elastomer for comparing silicone vs. neoprene rubber.

Silicone Polychloroprene (Neoprene)
Temperature Range -100° to 450° F -40° C to 230° F (Dry Heat Only)
Compression Set Excellent Good
Weather Resistance Excellent Good
Abrasion Resistance Poor Good

Silicone and Neoprene resist oils and greases, but silicone is also recommended for elevated temperature applications. Neither elastomer can withstand hydrocarbon fuels such as gasoline or diesel. Neoprene rubber is a good choice for some refrigerants.

Industries and Applications

Polychloroprene (Neoprene) is used in fluid sealing, refrigeration sealing, and in industries such as automotive, mass transit, construction, and defense. Examples of Neoprene products include door and window seals, O-rings, washers, bearing pads, vibration mounts, shock absorbers, and marine gaskets. With its good physical toughness and mechanical strength, Neoprene offers a good balance of performance properties.

Silicone is used in door and window seals, weather seals, and in appliances and electronics. This synthetic rubber is also used in high voltage insulation, outdoor cable protection, HVAC drains, and fluid transfer. Silicone has excellent aging properties in sunlight. Industries that use silicone products include mass transit, food service, healthcare, retail, automotive, construction, and defense.

Special Considerations for Silicone vs. Neoprene Rubber

Silicone is in short supply globally, but that’s no reason to select the wrong material when you’re comparing silicone vs. Neoprene rubber. By partnering with the right supplier, you can get the right silicone, Neoprene, or other elastomer that you need. For example, VIP Rubber supplies a 30-durometer silicone that meets the demanding requirements of the A-A-59588 3B specification, which superseded ZZ-R-765.

For defense and aerospace manufacturers, the 3B standard is especially important because it’s one of only two A-A-59588 classes that require flex-fatigue resistance – a measure of an elastomer’s ability to withstand repeated flexing or bending. Unlike a commodity silicone, this specialized elastomer is superior. To learn more, contact Vip Rubber.

by Cindy LeClair Cindy LeClair No Comments

Which Elastomer Is Best For Your Project | Find Out Now

Understanding Polymers In Custom Manufacturing

Vip Rubber and Plastic Elastomers and MaterialsA basic understanding of polymers can be incredibly helpful when creating a new part from rubber or plastic. It is important to choose the right material to ensure product performance and longevity. It takes many years of experience to reach “expert” status in the rubber and plastic industry.

With over half a century of manufacturing under our belt, we have deep understanding of what is involved in the selection, preparation and testing of materials. The heavy lifting can be left to our experts, but for those looking for a fundamental understanding of polymers, read on…..

Definition of Polymer

“A substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together, e.g., many synthetic organic materials used as plastics and resins.”

POLYMERS can be classified into three categories:

  • Plastics
  • Rubber & Elastomers
  • Fibers

The rubber industry only has a few natural polymers that are available for use without making any significant changes to them. In terms of elastomers, natural rubber is the only natural elastomer available. All other elastomers are synthetic and require specific methods of modification to become usable in manufacturing.

ELASTOMERS are typically segmented into three categories. These categories are very useful when selecting the type of rubber for a job or application.

General Purpose: Best for parts that will not require resistance to petroleum-based fluids. These elastomers are made only from carbon and hydrogen and perform well, but will not resist the effects of petroleum oils.

  • Natural Rubber (NR)
  • Polyisoprene (IR)
  • Polybutadiene (BR)
  • Styrene-butadiene (SBR)
  • Butyl (IIR)
  • Ethylene-propylene (EPM)
  • Ethylene-propylene-diene (EPDM)

Solvent Resistant: Good for parts used in environments with exposure to petroleum-based fluids. With a more robust dynamic composition, solvent resistant materials will resist petroleum based fluids.

  • Nitrile (NBR)
  • Polychloroprene (CR)
  • Polysulfide (T)
  • Epichlorohydrin (CO)
  • Chlorinated Polyethylene

Temperature Resistant: Best choice for parts that will be exposed to extreme temperatures for long periods of time. Usually can withstand both abnormal temperatures and petroleum-based fluids.

  • Polyacrylate (ACM)
  • Fluorocarbon (FKM)
  • Chlorosulfonated polyethylene (CSM)
  • Silicone (MQ)

Not all materials fit perfectly into these three categories, with many hovering on the border. A custom compounder can alter elastomers to fit the exact needs of a part, including spec requirements for aerospace, military, automotive and other industries.

Elastomer choice is a critical starting point for every custom manufacturing project. It is important to select a material that will perform properly and provide lasting results.

Contact us today to get started on your project.

Cindy LeClair is the Vice President of Marketing at Vip Rubber and Plastic Company in California. Cindy is in the third generation of family ownership and has over 10 years of experience in the manufacturing industry. She is passionate about helping others and aims to educate and connect customers with the right resources. Should you want to get to know Vip Rubber and Plastic better as a potential supplier, do not hesitate to reach out to Cindy.