As the name implies, closed-cell foam consists of completely closed holes. The cells are pressed together so that air and moisture cannot get inside the foam. As a result, closed-cell foam is stiffer and more stable than open-cell foam.
Closed-cell foam is made by applying a gas, such as nitrogen, to a rubber or plastic compound that is under high pressure. The foam can be made by direct contact with the gas or by adding a gas-forming agent to the material.
Typically, closed-cell foams tend to be water resistant due to the closed nature of the pores that make up the foam. The smaller and more compact these cells are, the more water-resistant the material will be. When used in solid form, closed-cell foams are non-toxic. In fact, these types of foams are commonly used for food and medical purposes. Closed-cell foams are toxic only when in liquid or gaseous form during the manufacturing process.
Figure 1. Closed-cell foam.
Customers are sure to find that Alfa Chemistry's large range of closed-cell foam products provides the ideal solution for their upcoming projects, from flexible polyethylene to rigid polystyrene.
Due to the wide variety of available closed-cell foams, there is a wide range of applications.