Chapter 11

Chapter 11 - HUEC 2040 CHAPTER 11 TEST 3 10-24-2005...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
HUEC 2040 TEST 3 10-24-2005 C HAPTER 11 E LASTOMERIC F IBERS - A natural or synthetic polymer which at room temperature can be stretched repeatedly to at least twice it’s original length and which after removal of the tensile load will immediately forcibly return to approx its original length. E LASTOMERIC F IBERS - Rubber - Natural -Spandex - Man - Polyurethane - Elastoester - Japan - Anidex - Germany - Not produced in U.S. R UBBER -Natural rubber plants -Liquid latex -Yields 4 pounds annually -Synthetic rubber polymers -Neoprene -Natural polymer -Most important and widely used -Tires -Isoprene -Not good for long term stretch recovery -Vulcanization -The process where fibers are formed by splitting thin film of cross-linked rubber polymers into fine strands -Provides “memory” which means it can go back to its original position after being stretched. N ATURAL R UBBER A DVANTAGES -High stretch -High Elasticity -High Flexibility -Good Strength -Non-absorbency -Fire-resistant -There is a high Footfall: sound abortion which means when the shoe hits the floor you don’t hear it. N ATURAL R UBBER D ISADVANTAGES -Deterioration -Sunlight -Oils -Petroleum 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
HUEC 2040 TEST 3 10-24-2005 -Aging N ATURAL R UBBER U SES -Elastic bands, erasers -Waterproof fabrics -Elastic bands -Balls, tires S YNTHETIC R UBBERS -Polyisoprene -Most common -Lastrile or nitrile rubbers -Very resistance to oils -Polychloroprene -Chloroprene units -Characteristics similar to natural rubber -Better resistance to deterioration -Low resistance to stretching, elastic recovery -U.S. film coating fabrics S PANDEX -1959, produced in the U.S. under the trade mark name of Lycra -A manufactured fiber in which the fiber forming substance is a long- chain synthetic polymer comprised of at least 85% of segmented polyurethane -Dupont -Lycra ® spandex -Dry spun -Globe manufacturing Co. -Glospan ®, Cleerspan ® -These were done by reaction spinning S PANDEX P ROPERTIES -Physical Appearance -Cross Section: Round, peanut, dog bone, rectangular -Longitudinal: Smooth -Strength -Weak -Elongation & Recovery -High elongation -Excellent Elastic Recovery -Absorbency & Moisture Regain -Low - takes dye better than rubber -Water penetrates the fiber -Wicking - good -Effect of Heat -Burns & Melts: sticky at 340 degrees F -Can be heat set -Machine dryable -Chemical Reactivity -Good resistance to perspiration and seawater 2
Background image of page 2
HUEC 2040 TEST 3 10-24-2005 -Some suntan oils, may yellow -Resistances -Microorganisms: satisfactory resistance -Light: discolors some whites S PANDEX U SES -Always used with other fibers, never 100% spandex -Higher level of comfort -More versatile clothing -Enhances every fabric - blended S PANDEX WITH OTHER FIBERS -Bare spun -Single covered wrapped yarn -Double covered yarn -Core spun yarn B ARE C ORE S PANDEX -Uncovered filaments -Woven or knitted into fabrics S INGLE C OVERED Y ARN -One layer of another filament fiber wrapped around spandex core D OUBLE COVERED YARN -1 st layer is twisted around core in one direction -2 nd layer is twisted around core in opposite direction
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/25/2008 for the course HUEC 2040 taught by Professor Staff during the Spring '08 term at LSU.

Page1 / 33

Chapter 11 - HUEC 2040 CHAPTER 11 TEST 3 10-24-2005...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online