Micro-fibers and Nano fibers
Yiping Qiu
Donghua University
Fall,2004
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
? Application
? synthetic leather
? specialty wipes
? ultra-high filtration materials
? artificial arteries
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
? 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
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
Nano Fibers
Applications
? Filtration
? Others?