FINAL REVIEW Chapters 1 2 Introduction Textile fibers What is the AATCC AATCC American Association of Textile Chemists and Colorists The world s leading not for profit professional association for the textile design materials processing and testing industries What is the difference between natural and manufactured fibers Name examples of each Natural any fiber that exists in its natural state Manufactured fibers derived from a process of manufacture from any substance What are cellulosic fibers Which is the most commonly used cellulosic fiber Cellulosic fibers are those that come from a plant source Most common is cotton Cellulosic fibers can come from different parts of the plant Name one example of each Seed hair cotton Stem flax Leaf agave Where do natural protein fibers come from Which natural protein fiber is different from all of the others They come from animal sources silk is different because it s the only natural filament fiber What is the difference between an amorphous and crystalline fiber structure How can this affect the performance of the fiber Refers to the polymer structure of a fiber Amorphous is a random order and crystalline is orderly Amorphous are weaker has more stretch and have a lower luster What is luster in a textile Amount of light reflected by the fiber What is the meaning of the four properties we use to describe fiber Physical color shape and contour Mechanical strength flexibility and elongation Chemical absorbency hydrophilic and hydrophobic Environmental Sensitivity to Microorganisms and Insects Sensitivity to Environmental What is the difference between absorption and adsorption The ability of a fiber to absorb water vs the fiber pushing the water out What does hydrophobic mean Hydrophilic Fiber readily absorbs water or other liquid Hydrophobic Fiber does not absorb water readily Hygroscopic Ability of a fiber to take up and retain moisture from the air does not readily release by evaporation Oleophilic Has a strong affinity for oil based substances How does burning a fiber determine which generic group it belongs to protein cellulose and thermoplastic inorganic Each types of fibers burns in different ways For example thermoplastics with melt and cellulosic s are highly flammable Inorganic s do not burn at all and proteins burn but not as well as cellulose How does electrical conductivity of a fiber relate to having problems with static Amorphic structures have large gaps which result in their ability to rub friction and pass electrons back and forth The passing of electrons is what causes electricity 3 Fiber Properties Conditions 4 Natural Cellulosic Fibers 5 Natural Protein Fibers What properties do cellulosic fibers have in common Good absorption slow to dry Subject to mold and mildew Low electrical conductivity no static cling Stronger when wet May shrink when washed does not melt Will scorch and burn Will continue burning when removed from flame Harmed by acids Resistant to alkalis Biodegradable Why are they stronger when wet They absorbs moisture the inner layers swell and push out against the primary wall providing strength How can you recognize cotton fibers under a microscope By its convoluted shape How is cotton processed Picking Ginning and Carding or combing to align the fibers Comes from seed hair How is linen processed What part of the plants do these fibers come from Retting Breaking Scutching and Hackling Comes from the stem of a plant What is a bast fiber What is the most common bast fiber used for clothing How is it processed Bast Fibers are cellulosic s that come from the stem of a plant What are some other plants used for fiber What are the major uses for jute Hemp jute flax kapok milkweed Jute is used for erosion control or burlap Why can t hemp be grown in the United States Because it is closely related to marijuana Although it is possible to make regenerated protein fibers from soy or milk all commercially used protein fibers are natural What is the most used animal fiber Sheep s wool What breed of sheep produces the most valuable and finest wool Merino What is virgin wool Is wool that has not previously been used in manufacture What are some other animal fibers that are used for textiles Camel alpaca llama and angora What are the properties that animal hair fibers have in common Very absorbent hydrophilic Hygroscopic absorbs readily but does not release moisture Slow to ignite do not burn easily Easily damaged by alkalis bleach and sunlight Damaged by some insects moths carpet beetles How do protein fibers burn Slow to ignite do not burn easily How can you recognize wool and other animal hairs under a microscope They have scales What is the only natural filament fiber Silk Where does silk come from How is it processed What is raw silk It comes from silk worms Usually the silkworm is killed by heat so it will not break the cocoon the silk is reeled from the cocoon Raw silk is where the sericin has not been removed What is tussah silk obtained from cocoons of silkworms in natural habitat What is sericulture The cultivation of silk What does the cross section of silk look like Triangular What is the difference between reeled and spun silk Fibers that can t be reeled are carded and spun What is weighted silk Silk is treated with metallic salts Absorbs dye more easily Adds body to the fabric Over time makes silk more fragile How do the properties of silk differ from other animal fibers The fiber is smooth lustrous Cross section of fiber is triangular Fiber has crystalline structure very strong Good absorbency easily dyed Self extinguishes when burned Why are manufactured cellulosic fibers called regenerated Begins with natural sources of cellulose Produced from natural substances containing cellulose or protein in an unusable form Why are the properties of the manufactured fibers similar to the natural cellulosic fibers Because some were regenerated from actual cellulosic fibers where other are made to be like cellulosic s What are the steps to produce a regenerated fiber Treated with chemicals to produce a solution that can be regenerated or reformed as a fiber 6 Manufactured Cellulosic Fibers What does the cross section of rayon look like What does a length of the fiber look like under the microscope The cross section is serrated making striations along length What are some of the end uses of rayon Apparel interior fabrics and leftovers are used for non woven products like cotton balls What is the difference between the