Skip to main content

Foams & Elastomers

Everywhere you look you see some type of foam rubber gasket or weatherstripping.  In windows or appliances or medical devices or lighting fixtures, you will find foams and elastomers. They all look different, though.  Why is that and what are the different reasons for using them?

First off, let’s define what a foam rubber is.  Essentially it is a rubber or plastic that has been manufactured with a foam agent to create air bubbles in a matrix design throughout the material. This makes the rubber or plastic more pliable and compressible, which helps them perform better as a cushion and/or seal. 

Now let’s talk about why someone would use a foam rubber.  Whether it is for a seal or bonding, typically they are used for one of three reasons or applications:

  1. Create a seal so air, dust, or moisture cannot get through.
  2. Act as a cushion or space between two surfaces so they do not rattle or cause damage to each other.
  3. Act as insulation against heat and/or cold.

Open Cell vs. Closed Cell

Once the application is determined then the next step is to determine which of the many foam rubber products are best for you.  One of the first determinations is whether you need an Open Cell foam or a Closed Cell foam. The differences are: 

  • Open Cell – The cells are not fully closed so they can absorb liquids or dust, thus allowing them to potentially flow through the foam.
  • Closed Cell – The cells are fully closed so liquids, air, or dust cannot get into the foam.  Typically, these are more stable and rigid than Open Cell. 


After this determination there are many product characteristics of the foam that you need to consider:

  • How easy do you want it to compress?
  • What temperatures does it need to withstand?
  • Does it need to be flame retardant?
  • For the application does it need to be absorbent or does it need to keep a tight seal? 
  • Does it need to stretch?
  • Is it to be used outdoors or indoors?

These questions, among others, will help determine the foam rubber that will give you the best performance and find the best material.  These materials can be:

PLITEK® has experience with all these materials and can answer these questions for you.  Please do not hesitate in contacting us to help you find the ideal solution for your needs. 

PLITEK® is an ISO 9001:2015 and ISO 13485:2016 certified global converting leader.