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Science Forum Index » Materials Forum » polyethylene/propylene nanotube Damascus
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Message |
| Richard Saam |
 Posted: Tue Sep 23, 2003 6:17 am |
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Guest
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Hi All,
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
Richard Saam |
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| William Kaukler |
| Posted: Fri Sep 26, 2003 6:49 am |
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Guest
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Quote:
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
Along with the nanotubes.
Fine idea, but I think it was recently published that PVA was used.
Co-extrusion I believe. Although the Japanese folding method or Damascus
process was not applied and seems viable. I'd call in a taffy puller if
enough material could be amassed.
Dr. K |
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| Bill |
| Posted: Fri Sep 26, 2003 6:50 am |
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Hallo, sounds to me that what is needed is the resin or binder that is
used in injection moulding of metals.
I don't know the process in detail, but I believe that the metal
powder is injection moulded on "normal" machines, e.g. Arburg, into a
green state, using a binder which is similar to wax or low M.Wt. PE.
The soft parts are then placed in an oven and the binder is
"evaporated", leaving the parts in a "brown" state. The metal powder
is then fused to form the finished part by a process like sintering.
Wonder if those metal injection moulders have already tried moulding
nanotubes? I know two such companies in the UK. One is located in
Ipswich. Think it's called Manganese Bronze, and another in
north-west of UK, but don't know the name.
Regards,
Bill
Richard Saam wrote:
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized
off. |
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| John Spevacek |
| Posted: Fri Sep 26, 2003 6:50 am |
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Guest
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Richard Saam <rdsaam@att.net> wrote in message
news:<bkpdko0u5p@enews4.newsguy.com>...
Quote: Hi All,
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
You can't get that high of draw ratios with PE or PP ... unless you
work with gelled UHMWPE and spin it. Pricey.
John |
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| JCS |
| Posted: Wed Oct 08, 2003 1:41 am |
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Guest
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"Richard Saam" <rdsaam@att.net> wrote in message
news:bkpdko0u5p@enews4.newsguy.com...
Quote: Hi All,
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
Richard Saam
I know Dr. Frank Ko's group at Drexel has worked with CNTs and
electrospinning. The result is a sub-micron sized polymer fibers
encapusulating CNTs. The polymer could be vaporized off or dissolved away
using the proper solvents.
The problem with electrospinning is that you can't control fiber orientation
very successfully. Non-woven felt-like mats are usually produced in the
process.
JCS |
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| Ernie |
| Posted: Wed Oct 08, 2003 9:07 am |
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"JCS" <rastanura@removeme.hotmail.com> wrote in message
news:bm0f3j022sa@enews3.newsguy.com...
Quote:
"Richard Saam" <rdsaam@att.net> wrote in message
news:bkpdko0u5p@enews4.newsguy.com...
Hi All,
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
Richard Saam
I know Dr. Frank Ko's group at Drexel has worked with CNTs and
electrospinning. The result is a sub-micron sized polymer fibers
encapusulating CNTs. The polymer could be vaporized off or dissolved away
using the proper solvents.
The problem with electrospinning is that you can't control fiber
orientation
very successfully. Non-woven felt-like mats are usually produced in the
process.
JCS
Using glass fibers as analogy for nanotubes, during processing under high
shear conditions, the glass fibers line up in the flow directions. One
would expect the nanotubes to do the same (provided they have a high enough
aspect ratio [length/width]). Extrude or injection mold a resin containing
the nanotubes, and the Damascus Steel process may not be needed. To
maximize shear, use highly viscous (high MW) polymer, and force the blend
through very small and long die.
As you suggest, you can decompose or burn off the polymer, but be aware of
fire and explosion potential of gases generated.
Regards,
Ernie |
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| Nanocyl |
| Posted: Thu Oct 09, 2003 6:55 am |
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Guest
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Hello,
We have results of nanotubes /PP composites fibers which have been
stretched in order to align nanotubes along the axis of the fiber
using common polymer equipment. Tenacity of the fibers is superior to
Kevlar and similar to UHMWPE Dyneema with only 3%wt. of MWNT.
Injection molding do not align nanotubes which are wavy, so you do not
get any significative reinforcement.
Fiber Composites manufacturing needs a binder to provide adhesion. Its
mechanical contribution is small compared to the contribution of the
high modulus or strength fibers.
BTW, half of the fuel lines in cars in the US contains already MW
nanotubes.
Olivier
Nanocyl
"Ernie" <Ernieman_NOSPAM@charter.net> wrote in message
news:<bm198a010g8@enews2.newsguy.com>...
Quote: "JCS" <rastanura@removeme.hotmail.com> wrote in message
news:bm0f3j022sa@enews3.newsguy.com...
"Richard Saam" <rdsaam@att.net> wrote in message
news:bkpdko0u5p@enews4.newsguy.com...
Hi All,
There seems to be some interest in aligning carbon nanotubes in one
direction.
What if one mixed aggregate carbon nanotubes with molten PE or PE and
then extruded. Then using the method after Damascus Steel, keep
melting, stretching and folding over 10's , 100's , 1000's of times.
The carbon nanotubes would be eventually aligned in one direction.
Now to remove the PE or PP matrix?? Possibly it could be vaporized off.
Richard Saam
I know Dr. Frank Ko's group at Drexel has worked with CNTs and
electrospinning. The result is a sub-micron sized polymer fibers
encapusulating CNTs. The polymer could be vaporized off or dissolved away
using the proper solvents.
The problem with electrospinning is that you can't control fiber
orientation
very successfully. Non-woven felt-like mats are usually produced in the
process.
JCS
Using glass fibers as analogy for nanotubes, during processing under high
shear conditions, the glass fibers line up in the flow directions. One
would expect the nanotubes to do the same (provided they have a high enough
aspect ratio [length/width]). Extrude or injection mold a resin containing
the nanotubes, and the Damascus Steel process may not be needed. To
maximize shear, use highly viscous (high MW) polymer, and force the blend
through very small and long die.
As you suggest, you can decompose or burn off the polymer, but be aware of
fire and explosion potential of gases generated.
Regards,
Ernie |
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