Design of Polymers for Industrial Applications: Tyvek

What is Tyvek?

• High density polyethylene fibers

• Strong material, difficult to tear, but can be cut with scissors

• Breathable material: water vapor can pass through, but not liquid water

Structure of Tyvek: Nonwoven material

• Nonwoven material: fabric-like material made from fibers

• Fibers are bonded together by treatment • Flat and porous • Other examples of nonwovens:

–laundry aids (fabric dryer-sheets) –sterile wraps, caps, gowns, masks and

draping used in the medical field –filters (coffee)

Structure of Tyvek

• Fibers are essentially bonded together as they are pushed on a moving belt

History

• 1955: discovered by accident at DuPont

• At the time, they developed a new technology to fast-spin the fibers

Properties of Tyvek

• Lightweight: higher strength-to-weight ratio than paper!

• Water and moisture resistant • Strong and rip-resistant • More elastic than paper • 100% recyclable!

Other Properties

Journal/Group Activity

• BRAINSTORM: Get into groups of 3-4 students and discuss some uses of this material. Where would the use of Tyvek be beneficial?

• State specific properties mentioned and how they could be useful in different applications.

• Describe these applications and your reasons in your journal.

Supplementary Slides

Websites and Resources • http://matse1.matse.illinois.edu/polymers/pri

n.html