Extruded Vs. Cross-linked PE Foam

Also called PE foam, polyethylene foam is the most commonly used type of plastic. They are made using polymerized monomers, which produce the same stable thermoplastic, but there are various polymerization methods that can produce different kinds of PE foam. The properties of different PE foam types depend on the specific polymerization process. These processes can be grouped into different categories, and one common classification that is frequently used in manufacturing is that of low-density polyurethane foam. It possesses similar qualities to basic ethylene, which is highly resistant to chemicals. It also has a semi-rigid structure, being a closed-cell foam, and has varied textures. Low-density polyethylene foam may look like urethane foam or polystyrene foam but can be differentiated by the process in which it is created.

The two primary types of low-density polyethylene foam are extruded and cross-linked low-density PE foam.

The former one is formed using a halogenated hydrocarbon. Utilizing high pressure, the foaming agent and the PE foam are combined inside a chamber and then forced out via a die opening where the atmospheric pressure causes it to expand and then cool and solidify. This continuous process creates a solid low-density PE foam.

The other type of PE foam is cross-linked foam, which is made either continuously or in batches. Unlike its extruded counterpart, producing cross-linked PE foam can be quite restrictive. Forming them involves similar processes, in that the agent is utilized to mix with a solid PE that is then subjected to a higher temperature to attain the required cross-linking between the mixtures. After this, the temperature is further elevated to successfully create the final form of the polyethylene foam. This process of using a chemical cross-linking agent is performed in batches while PE foam cross-linked through radiation is a continuous process.

Finally, though both of these low-density PE foams may look very the same, they vary in the size of their cells. Extruded foams have bigger cells that are also harder than cross-linked PE foams.

Whatever the type of polyethylene foam you need, you can count on us at Alcot Plastics to supply the best products at the best prices. Contact us today to learn more!