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FASH 15 textiles synthetic fibers. synthetic fibers the polymers for synthetic fibers are synthesized or made from small simple molecules (not naturally occurring) often petroleum-based chemicals (petrochemicals) using complex procedures—less than 1% of total use per year
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FASH 15 textiles synthetic fibers
synthetic fibers the polymers for synthetic fibers are synthesized or made from small simple molecules (not naturally occurring) often petroleum-based chemicals (petrochemicals) using complex procedures—less than 1% of total use per year different chemical compounds used to produce nylon, polyester, olefin & acrylic
synthetic fibers—common properties heat sensitivity —fibers that soften or melt with heat; differ in their level of sensitivity; use care washing, ironing & dry cleaning chemical resistance —fibers do not absorb water, solvents, acids, or bases; resist soiling; difficult to dye piling —formation of tiny balls (tangled fiber ends) on fabric surface due to abrasion; strength of fibers keeps balls from falling off naturally
synthetic fibers—common properties static electricity—generated by friction; more rapid in cold, dry regions; attracts dust, soil, & lint—brushing to remove increases problem oleophilic—high affinity for oils & greases
synthetic fibers— common manufacturing processes: melt spinning http://www.youtube.com/watch?v=nr8cbpAt9oQ
participation activity: • melt spinning • …working in groups of 4, collect the necessary equipment • tweezers • candle • matches • …once you have set up your “lab”carefully take turns trying out melt spinning • heat the fabric until some melts • quickly draw out the melt with tweezers • HOW UNIFORM ARE YOUR “FIBERS”? • polyester fabric (4 pieces) • cup of water • foil
synthetic fibers— common manufacturing processes drawing—aligns molecules in more parallel, crystalline, oriented arrangement; drawn to develop desirable strength, pliability, toughness & elasticity heat setting—uses heat to stabilize the shape & dimensions of yarns or fabric; after cooling, fabric/ yarn stable at heat lower than at which it was set
synthetic fibers—identification burn tests used to identify presence of some; not good for blends or fibers that are flame-retardant or heat resistant—does not identify specifics microscopic appearance not reliable because so easily modified solubility tests only procedure that differentiate among synthetics
synthetic fibers—common modifications • fiber shape & size • because of melt-spinning process, changing cross-sectional shape is relatively easy—spinneret hole • hollow fibers provide better thermal properties & lighter weight, hide soil • trilobal, pentalobal, & multilobal fibers used in apparel & interiors • flatribbon fibers used in formalwear • channel fibers used in activewear
synthetic fibers—common modifications low-piling fibers—engineered to minimize pill formation; decreases fiber’s flex life high-tenacity fibers—produced by combining drawing with molecular-chain-length modifications; tow ropes, air bags, parachute cords low-elongation fibers—stretch less under force, but as strong as regular fibers; apparel & interior items that receive hard use—work apparel & heavy-duty upholstery
synthetic fibers—nylon the first synthetic fiber—1939 by DuPont introduced to public in women’s hosiery unlike any fiber in use at the time—stronger, more abrasion resistant, excellent elasticity, heat set, lightweight, chemical resistant also had drawbacks—static buildup, poor hand, poor comfort on skin, low resistance to sunlight http://www.youtube.com/watch?v=yFEHKRdXb9Y&feature=related
synthetic fibers—nylon production—made from various substances; numbers after name indicate # of carbon atoms in starting materials nylon 6,6 physical structure—available in multifilament, monofilament, staple in a variety of lengths & tow in a wide range of deniers & shapes, as partially drawn or completely finished filaments produced in bright, semi-dull & dull lusters with varying degrees of strength
synthetic fibers—nylon physical structure
synthetic fibers—properties of nylon aesthetics—smooth, lightweight, high strength; can be lustrous, semi-lustrous, or dull; varied drape depending upon use; voids & flat sides scatter light & hide soil durability—outstanding durability; excellent strength & high elongation; excellent abrasion resistance comfort—not as comfortable to wear as natural fibers; great for wind- and water-resistant jackets
synthetic fibers—properties of nylon • appearance retention— • highly resilient due to heat-setting; pleats, creases & embossed designs become integral • compressional resiliency important in carpets • shrinkage resistance high due to heat set & low absorbency • care— • hot water may cause permanent wrinkling but can help remove oily stains • color scavenger • dries quickly • resistant to mildew, insects & fungi; low sunlight resistance
synthetic fibers—nylon • environmental concerns & sustainability • all concerns associated with petrochemicals—made from by-products (waste) • production consumes more energy than polyester or cotton • nitrous oxide is emitted from production facilities • processing uses few cleaning chemicals • less water, salt & acid used for dyeing • recycling reasonable—carpet recycled to a nylon 6 raw material or mixed with plastic or concrete; performance enhancing additives pose challenge
synthetic fibers—nylon environmental concerns & sustainability
synthetic fibers—nylon uses • most important—carpets • apparel: • lingerie, hosiery, socks • sporting goods—tents, sleeping bags, • average car uses 25 lbs of fiber—upholstery, carpet, head liners, door & visor trims • umbrellas, clotheslines, toothbrush, hair brush • luggage, backpacks
synthetic fibers—polyester first produced in England—introduced in the US in 1951 by DuPont most widely used synthetic—“workhorse” filament extremely versatile while staple can be blended with many other fibers—versatility in blending is unique advantage produced by reacting dicarboxylic acid with dihydric alcohol—fibers are melt-spun & hot-drawn
synthetic fibers—physical structure of polyester produced in many types: filaments—high- or regular-tenacity; bright or delustered; white or solution-dyed; regular or low-piling generally smooth rodlike fibers with circular cross-section other cross-sections: trilobal, octolobal, oval, hollow, voided, hexalobal, pentalobal (star shaped)
synthetic fibers—properties of polyester aesthetics—blend well, maintaining natural fiber look & texture; microfibers particularly suited to high-fashion because of versatility & durability durability—excellent abrasion resistance & strength; better sunlight resistance comfort—poor absorbency lowers comfort factor; finishes & fiber modifications increase comfort appearance retention—generally wrinkle resistant except when set by body heat and moisture care—wash warm, machine dry medium heat, remove promptly, hang, touch up with steam
synthetic fibers—polyester • environmental concerns & sustainability • similar to nylon—petrochemicals • production energy less than nylon more than cotton • uses small amounts of water during production • uses toxic catalytic agents that contaminate soil & water—long term environmental impact • extensively recycled—creates significantly less pollution than creating virgin fibers
synthetic fibers—polyester uses • most widely used MF in US • woven fabrics in apparel & interiors • knitted fabrics • fiberfill • nonwoven or fiberweb fabrics • tirecord • carpets • technical hoses, belts, • artificial arteries, veins & hearts
synthetic fibers—olefin by 1957 Italy was producing olefin, US in 1960 has a combination of properties that makes it good for interiors, apparel that does not need ironing & technical uses production —two processes; high-pressure—film & molded materials & low-pressure—textile use melt-spun into water or cool air & cold drawn to six times its spun length—crystallizes very rapidly gel spinning—dissolved polyethylene forms viscous gel in solvent; produces very high-strength fibers
synthetic fibers—olefin physical structure— produced as monofilament, multifilament, stapled fiber, tow, and slit or fibrillated film yarns fibers are colorless, often round in cross-section & have slightly waxy feel; cross section modified according to end use
synthetic fibers—properties of olefin aesthetics—usually produced with medium luster & smooth texture; many sizes available; waxy hand; drape varied according to end use durability—produced with different strengths according to end use; very durable & strong, lightweight; excellent resistance to chemicals comfort—nonabsorbent; excellent wicking; good heat retention appearance retention—excellent resiliency & recovers quickly from wrinkling
synthetic fibers—properties of olefin • care— • easy-care characteristics; suitable for a number of end uses • dry quickly • dry cleaning not recommended due to solvents • waterborne stains no problem • does not pick up color • oily stains are extremely difficult to remove • excess heat cause fiber to shrink & melt • excellent resistance to acids, alkalis, insects & microorganisms
synthetic fibers—olefin • environmental concerns & sustainability • similar to nylon—petrochemicals • easier to recycle than most fibers—used in packaging materials • seldom dyed • used in many products that protect environment— • erosion control fabrics • weed barrier fabrics • protective covers for vegetables & flowers • hazardous waste transport container liners
synthetic fibers—olefin uses apparel—underwear, socks, sweaters, glove liners; hosiery, saris, swimwear, wind- water- and cold-barriers in active & outdoor wear; Thinsulate interior textiles—carpeting, upholstery, draperies & slipcovers; almost completely replaced jute as carpet backing; nonwoven fabrics—furniture webbing; mattress covers technical—geotextiles, roadbed-support & stabilizer fabrics, car & boat interiors, boat
synthetic fibers—acrylic first made in Germany in 1893 marketed frequently as being wool-like production—some dry- or solvent-spun, others wet-spun physical structure—cross-sectional shape varies according to spinning method
synthetic fibers—properties of acrylic aesthetics—attractive & have soft, pleasant hand; bulky spun yarns are usually textured to be wool-like; matte luster; almost always staple fibers durability—not as durable as nylon, polyester or olefin; satisfactory for apparel & interiors—withstand reasonable abrasion; piling can be noticeable comfort—moderately comfortable because of irregular surface, low absorbency, lightweight, wicks well
synthetic fibers—properties of acrylic appearance retention—moderate resiliency & recovery from bending—resist wrinkling; shrink when exposed to high temps & steam; cannot be heat-set; solution dyed colors are permanent care—especially important to follow care label instructions with acrylic; care varies due to modifications or blends
synthetic fibers—acrylic • environmental concerns & sustainability • resistant to natural sources of degradation • production chemical require significant processing • recycling of solvents used in spinning is necessary to minimize environmental impact • wet-spun require washing & drying to remove chemicals • used more energy & water than polyester • not recycled
synthetic fibers—acrylic uses • relatively minor fiber in terms of use—mostly apparel, some interiors & technical • fleece fabrics, sweaters, socks • pile fabrics & faux furs • craft yarns • upholstery fabrics • drapery fabrics • blankets • carpets & rugs • awnings, tarps, luggage, boat covers • outdoor furniture, tents, filtration fabrics