Environmental Engineering Reference
In-Depth Information
Processing
Structure
Property
FiguRe .
Structure-Property-Processing.interrelationship.for.materials.
. RaMiFiCations oF woRkeR exPosuRe and
enViRonMental issues FoR nanoManuFaCtuRing
In.considering.the.progression.of.manufacturing.processes.with.respect.to.the.work.
environment,. there. has. been. a. general. trend. over. the. past. hundred. years. toward.
improved. safety,. with. signiicant. advances. made. in. the. major. industries.. The. rate.
of.change,.however,.can.vary.by.industry..Industries.with.a.long.history.and.large,.
expensive.capital.equipment.naturally.tend.to.move.more.slowly.than.newer.indus-
tries.that.germinated.with.computerized,.automated.equipment..For.example,.much.
of.the.forging,.casting,.and.sheet.metal.industry.is.still.represented.by.workplaces.
that. are. loud,. hot,. and. particulate-laden.. In. contrast,. the. biotechnology. industry.
relies.on.clean,.well-controlled.environments,.where.the.risk.is.more.of.the.unseen,.
in.both.process.and.waste.streams..Because.nanotechnology.and.nanomaterials.are.
anticipated.to.affect.both.of.these.industries.and.many.more,.the.question.arises.as.
to.how.the.manufacturing.environment.will.change..How.will.issues.of.worker.expo-
sure.and.environmental.impact.differ.for.nanomaterials?
3.3.1 F
Our
“g
eneratiOns
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OF
n
anO
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evelOpment
In.the.case.of.the.incorporation.of.nanomaterials.into.products,.several.generations.
of.changes.to.manufacturing.can.be.anticipated..Current.products.in.the.marketplace.
today.typically.fall.into.the.“1st.generation,”.where.relatively.minor.modiications.
to.existing.processing.equipment.were.needed.to.incorporate.nanomaterials.into.the.
product.. For.example,.surface.coatings.of.nanoibers. and. nanowhiskers.have.been.
used.for.improved.iltration.and.for.the.“nano-pants”.fabric.made.by.Nano-Tex.[3]..
More.than.20.years.ago,.Toyota.incorporated.clay.nanoparticles.into.polymer.resins.
to. create. automotive. body. panels. with. improved. strength,. toughness,. and. dimen-
sional.stability.[4]..These.types.of.nanocomposite.products.are.still.fabricated.using.
conventional. injection. molding,. extrusion,. and. cast. ilm. processes,. but. additional.
compounding. steps. or. other. modiications. to. the. processes. were. made. to. create. a.
