东华大学：《纺织材料学》课程教学资源（PPT课件讲稿，英文版）Micro-fibers and Nanofibers

Micro-fibers and Nano fibers Yiping Qiu Donghua university Fall 2004

Micro-fibers and Nano fibers Yiping Qiu Donghua University Fall, 2004

Micro fibers Definition Fibers of i denier Manufacturing of microfibers Bicomponent fibers ● Island in sea ● Citrus

Micro fibers  Definition ◼ Fibers of < 1 denier  Manufacturing of microfibers ◼ Bicomponent fibers: ⚫ Island in sea ⚫ Citrus

Island in sea Manufacturing process Suspension of droplets of one component in matrix of the other Two components should have similar melting temperatures Can make composite fiber To obtain the microfiber from the composite fiber, the matrix should be soluble such as polyvinyl alcohol Extremely small fibers possible: <0. 1 denier

Island in sea  Manufacturing process ◼ Suspension of droplets of one component in matrix of the other ◼ Two components should have similar melting temperatures ◼ Can make composite fiber ◼ To obtain the microfiber from the composite fiber, the matrix should be soluble such as polyvinyl alcohol ◼ Extremely small fibers possible: < 0.1 denier

Island in sea Application ■ synthetic leather a specialty wipes a ultra-high filtration materials artificial arteries

Island in sea  Application ◼ synthetic leather ◼ specialty wipes ◼ ultra-high filtration materials ◼ artificial arteries

Citrus or Segmented pie Manufacturing Two components: noncompatible but with similar T m such as pet and nylon 6 Citrus like or hollow citrus 米 NYLON HOLL OW PIE WEDGE TIPPED TRIL OBAL SEGMENTED CROSS CONJUGATE

Citrus or Segmented pie  Manufacturing ◼ Two components: noncompatible but with similar Tm such as PET and Nylon 6 ◼ Citrus like or hollow citrus

Nano fibers Electrospinning of nano fibers Principle o When electrical force at the sur face of a polymer solution or polymer melt overcomes the surface tension, a charged jets is ejected a Device Materials a Characteristics

Nano fibers  Electrospinning of nano fibers ◼ Principle ⚫ When electrical force at the surface of a polymer solution or polymer melt overcomes the surface tension, a charged jets is ejected. ◼ Device ◼ Materials ◼ Characteristics

Electrospinning Device Molymer soluton Capillary Fibcr formation △ High voltage Fiser mat Counter electrode Fromhttp://www.uni-marburg.de/phys-chemie/wendorftforschung/f1-elektrOspinninge.html

Electrospinning Device From: http://www.uni-marburg.de/phys-chemie/Wendorff/Forschung/F1-Elektrospinning_e.html

Electrospinning materials polyamides, polylactides, cellulose derivatives water soluble polymers such as polyethyleneoxide, polymer blends polymers containing solid nanoparticles or functional small molecules

Electrospinning Materials  polyamides,  polylactides,  cellulose derivatives,  water soluble polymers such as polyethyleneoxide,  polymer blends  polymers containing solid nanoparticles or functional small molecules

Nano fibers 0008 PC-SEM Ferrofibers": PVA(10%) Electrospun PVA (10%) and ferromagnetic nanoparticles(3.52% with SWNT(0.25%) Electrospun Nomex

Nano Fibers

applications Filtration ◆ Others?

Applications  Filtration  Others?