
With the development of Ethernet technology, and high data transmission requested, so higher performance and better quality Ethernet network cables are required. For example: 40 Gigabit Cat8 Ethernet cables, 600MHz 10Gigabit Cat7 Ethernet cable, Cat6a Ethernet cables… Today, China leading Ethernet cables manufacturer COMNEN engineers are going to talk about foaming PE insulation technology used in making ethernet network cables.
Overview
1, Ways of PE material foaming
3, The features of physical foaming PE insulation
4, How to realize PE material foaming
1, Ways of PE material foaming
There are two ways to realize PE foaming. One is Chemical foaming, the other is Physical foaming (Nitrogen foaming). But for some defects of chemical foaming, this way is gradually abandoned by most of the manufacturers.
2, What is physical foaming?
Physical foaming is a process of generating foam by introducing gas into a liquid polymer or a melt polymer. With inert inactive gas into the insulating dielectric layer uniform fine porous structure, among each other pores exist independently, similar to a sealed package.
3, The features of physical foaming
Firstly, foamed PE has a lower dielectric constant than solid PE. This means that it can better maintain the integrity of the electrical signal traveling through the cable, reducing signal loss and maintaining signal quality over longer distances.
Secondly, foamed PE insulation has a lower density than solid PE, which makes it more lightweight and easier to handle during cable installation.
Thirdly, the foam structure of the insulation creates a uniform air pocket that helps to maintain the geometry and impedance of the twisted pairs within the cable. This can reduce signal crosstalk and interference between the pairs, which can improve the cable’s overall performance.
Fourthly: Physical foaming can reduce the amount of material required to manufacture a product, resulting in cost savings and reduced environmental impact.
4, How to realize PE material foaming (Nitrogen Foaming)?
Please see bellow picture:

PE physical foaming process
The material used is polyethylene; the manufacturing process of the core wire under the temperature (+ 10 ℃), and then supersonic inject the Nitrogen into the PE materials to form uniform bubbles . Today skin-foam-skin used in insulating communication cable wires. As shown in Pic2,inner layer is a low density PE, the thickness is about 10μm closely adhered to the conductor, so that does not leave any gap between the two, and petroleum jelly prevent moisture penetration during the destruction of the longitudinal cable characteristics; foamed PE layer made substantial mixing from about 1% nucleating after extrusion machine injecting nitrogen form a uniform and closely integrated with the inner layer to avoid bubbles directly with non-continuous conductor adhesion and insulator loose. Due to the absence of such concerns, the degree of foaming can be increased to 60%; the outer PE layer keeps smooth appearance.
Full physical PE foaming production line:

PE physical foaming production line
In summary, foamed PE insulation is becoming more and more widely used in Ethernet network cables, to help maintain signal quality, make the cable easier to handle during installation, and reduce interference between signal pairs, to build high performance Cat8, Cat7, Cat6a shielded Ethernet cables and patch cables.
Any question of network cables, please don’t hesitate to contact us, our engineers will reply you in 24 hours, Email:sales@comnen.com