Dyneema® vs Kevlar

A Comparison of Ultra High Molecular Weight Polyethylene (UHMWPE-Dyneema®) to Aramid Fiber (Kevlar) Performance

UV Light Stability & Strength

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UHMWPE when exposed to UV light only losses about 5% of it strength over about a 2 day period. Glove cut resistance changes little due to exposure to sunshine.

Under the same conditions Aramid fiber losses about 25% of it strength over about 2 days. Performance deteriorates rapidly.

Heat Conductance & Comfort

UHMWPE yarn provides maximum comfort because it can disperse (body) heat quickly. It conducts heat like steel. Its heat conductance is 40 W/mk

Aramid fiber is insulative with a heat conductance of only 0.04 W/mK. Body heat cannot easily move off the skin and the gloves build up heat and become sweaty. 

Water Exposure 

UHMWPE fiber is water resistant. It does not swell or breakdown in water and it maintains performance in wet or humid conditions. It absorbs no water.

Aramid fiber absorbs about 3.5% of its own weight in water. The gloves become damp and sweaty and Performance deteriorates.

Strength

The world's strongest fiber : 15 times stronger than steel; 40% stronger than Aramid fiber. Aramid fibers are the second strongest: 7 times stronger than steel. 40% Less than Dyneema®.

Feel & Weight

UHMWPE is light weight: actual density is only 970 kg/m3. It floats in water and feels light and comfortable. Aramid fiber density is 1440 kg/m3 and it is heavier, more uncomfortable and bulkier in both garments and gloves.

Flexibility Comfort Durability

It is the only "superfiber" that does not break if bent or folded. The relative flex life of UHMWPE is 100 versus only 8 for Aramid fibers. This means performance remains the same no matter how many time the hand is flexed or fingers bend. All day performance.

Aramid fiber is more brittle than UHMWPE. Its flex life performance is 12 times worse than UHMWPE. As the hand is flexed and fingers bent the fiber cracks and breaks. Over time with each bending motion it looses its strength. Kevlar factories are covered in a "gold" dust because of this.

Abrasion Resistance 

 UHMWPE has the best abrasion resistance of all fibers. It abrasion performance is between 2.5 and 8 times better than other fibers. When conditions are wet it boasts even better performance up to 40 times better. The glove’s cut resistance performance remains predictably and consistently good.

Aramid fiber abrasion resistance is poor because of its poor flexlife. Tests have demonstrated that gloves made with Dyneema® have up to 20 times more abrasion resistance than gloves made with Aramid-based (spun) yarns. In a case study at Choice Fabricators Kevlar gloves wore out 4 times faster than Dyneema® gloves when used in the same operation.

 

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Washable & Skin Friendly

Gloves made with UHMWPE can be washed dozens of times with no loss in performance. They also meet the humano-ecological requirements for direct skin contact - Oeko-Tex std 100.Aramid gloves can suffer up to a 16% strength loss after just two washes. So cut resistance is significantly affected. According to Du Pont’s Kevlar® MSDS CKSQM, acute exposure to its fibrous dust can cause irritation to the mucous membranes of the nose and throat. 


*Information contained in this document has been obtained from various sources that are freely available in the public domain.

*Paz Performance accepts no liability nor warrants the accuracy of any performance data not specifically derived by Paz Performance.

*Dyneema® is the DSM’s Trademark for their UHMWPE fiber.

*Kevlar® is Du Pont’s registered trademark for its Aramid Fiber.