Difference Between Meta and Para Aramid

The key difference between meta and para aramid is that meta aramid is semi-crystalline, whereas para aramid is crystalline.

Aramid (aromatic + amide) is a polymer material which has many amide bonds as repeating units. Therefore, we can categorize it as a polyamide. It has at least 85% of its amide bonds attached with aromatic rings. There are two types of aramids as meta aramid, and para aramid and these two groups have different properties depending on the structure.

1. Overview and Key Difference
2. What is Meta Aramid
3. What is Para Aramid
4. Side by Side Comparison – Meta vs Para Aramid in Tabular Form
5. Summary

What is Meta Aramid?

Meta aramid is a polyamide having high heat resistance. The most common meta aramid is known as Nomex®. Generally, we manufacture this polymer material via wet spinning. The product of this method is a semi-crystalline fiber material. The most important features of meta aramid are heat resistance, abrasion resistance and resistance towards chemical degradation. The high resistance to heat makes meta aramid a good material for electrical insulation heat shields in vehicles. Moreover, we often use this material for the manufacture of protective clothing for firefighters.

Figure 01: Nomex®

Furthermore, there are two different forms of meta aramid as spun and continuous filament meta aramids. The spun-form is useful in the manufacture of clothing and other sewing applications while the continuous form is useful in reinforcement applications.

What is Para Aramid?

Para aramid is a type of polyamide having a high strength. The most common example of this material is Kevlar®. Moreover, para aramid is incredibly strong. The production method for this material is dry-jet wet spinning method. It gives a highly crystalline material as the product, which causes the high strength of this material.

Figure 02: Kevlar®

Para aramid also comes in two different types as spun and continuous filaments. Furthermore, the applications of this material include manufacturing protective gloves, hose reinforcement, etc.

What is the Difference Between Meta and Para Aramid?

Meta aramid is a polyamide having a high heat resistance while para aramid is a polyamide having a high strength. The key difference between meta and para aramid is that meta aramid is semi-crystalline, whereas para aramid is crystalline. Moreover, meta aramid is produced via wet-spinning while para aramid is produced via dry-jet wet spinning. The most common example for meta aramid is Nomex® while for para aramid it is Kevlar®.

Below infographic shows more details on the difference between meta and para aramid.

Summary – Meta vs Para Aramid

Reference:

1. Zande, Steve. “Meta and Para Aramid Physical Property Comparison.” USA Industrial Sewing Thread, Yarn Manufacturer, Worldwide Supplier, Available here.