Meta and Para Aramid Physical Property Comparison

When you are searching for a fiber or yarn for specific application requirements, there are many options to choose from. Meta-aramid and para-aramid yarns and threads are two popular choices for heat resistance and superior tensile strength.

Between Nomex™ and Kevlar™, you may find that one meets your specific needs however, you can also find comparable alternatives with similar properties and sizes from other aramid fiber producers.

Its important to understand the properties of meta-aramid and para-aramid to be able determine which is the best choice for your application.

The Key Differences Between Meta-aramid and Para-aramid Yarn

There are a few key differences between the two, specifically in the make-up of the fibers. Meta-aramids—commonly known as Nomex™—are temperature, chemical degradation and abrasion resistant. Meta-aramid is manufactured by wet spinning, the result is a semi-crystalline fiber with the molecular chain oriented along the fiber axis. They have a tenacity of about 5.6g/den and can withstand stress during fire exposure and high temperatures.

In contrast, para-aramids—commonly known as Kevlar™—are incredibly strong. Para-aramids are created using a dry-jet wet spinning method, resulting in a fully extended liquid crystal chain along the fiber axis. Para-aramids display a higher degree of crystallinity which increases the fiber’s strength. In fact, they are manufactured with a much higher tenacity of 23g/den.

The meta-aramid’s high resistance to heat makes it the perfect material for electrical insulation, protective gear and heat shields in vehicles. The para-aramid’s high strength and modulus is commonly used as strength members in cables, hose reinforcement and ballistics protection.