Showing posts with label Dupont. Show all posts
Showing posts with label Dupont. Show all posts

Sep 19, 2014

History of Kevlar

Did you know Kevlar was invented by a woman? Stephanie Kwolek took a temporary position for DuPont during 1946. Her goal was to save enough money to pay for medical school. By 1964 Stephanie was still working there and doing research on how to change polymers into higher strength synthetic fibers. She was working with polymers that possessed rod-like molecules that were all lining up in a single direction.

In contrast to the molecules that had been forming in bunches, Stephanie believed that uniform lines would render the resulting material more powerful, although such polymers had been quite challenging to break down into a testable solution. She finally developed the correct solution that had rod-like molecules and at the same time looked dissimilar to every other molecular solution she had yet made.

The next step was to put it through a spinneret, a device that could generate the fibers. The operator for the spinneret initially refused to allow Kwolek to operate the machine, because her new solution was so different than any other before it, and he believed it would ruin the machine.

Kwolek refused to give up and made a fiber, which was as tough as steel. The material was then named, Kevlar and since that time it has been utilized for radial tires, brake pads, drums, skis, helmets, camping gear as well as suspension bridge cables. The most widely known use for Kevlar is bulletproof vests. Kevlar was a brand name, but has become generic term. In July 1995, Kwolek was inducted into the National Inventors Hall of Fame. Perseverance counts.

Apr 27, 2010

Vegan Dental Floss

Yes, that's correct. Dental floss with "no mint and has a natural Cinnamon Flavor and it is completely free of all animal source ingredients" is being pushed by at least one company.

Use of dental floss with waxed silken thread came about in about 1819, but the use of dental floss was not common because silken thread was too expensive. During World War II, Dupont began using nylon and it replaced silk as the new material for many products, including dental floss. Of course, there are resin-coated nylon and teflon coated floss, but they do not use animal parts either.  Not sure what kind of  "animal source ingredients"   are found in synthetic materials..