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 | | From: | grant | | Subject: | Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | 17 Jan 2005 08:13:48 -0800 |
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 | I am currently trying to source an acrylic adhesive that fulfils the
following requirements, and I would appreciate any product suggestions.
Thanks
Grant
Requirements:
1/ Must be structural, very high strength
2/ Must be gap filling
3/ Must be clear after setting (no colouration, no bubbles released
from solvent evaporation)
4/ Must be unaffected by long term UV or Sunlight
5/ Must be permanently submersible in water (fresh and sea water)
6/ UV setting adhesives cannot be used due to nature of the join
7/ Must not give off extremely noxious vapours on setting
8/ Must be distributed in Europe
9/ Easily dispensed would be appreciated
The product is intended to bond cast, extruded and formed acrylic
together in a high-pressure, load bearing application. The intention is
to anneal the acrylic either before bonding or after. (Annealing and
setting the adhesive at the same time - I would be interested to know
some opinions on doing this together)
I have currently tested some products, specific polymer adhesives more
than general adhesives. I have tested:
IPS Weld-On #16 - seemed to fulfil the requirements except for the
bubbles released from the solvent. I have tried cooling the
solvent-based adhesives to 5deg =B0C before use to limit the bubbles
formed, but the result was still unsatisfactory.
IPS Weld-On #40/42 - has a yellow colour tinge.
A 'self-mixed' adhesive of Bostik Extrufix with acrylic cuttings
added to form a paste - seemed to fulfil the requirements except for
the bubbles released from the solvent.
Bostik Tensol #3 - From the specification it seemed this would fulfil
the requirements perfectly, however in use it gives of the most noxious
vapours.
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| | From: | jtnospam at yahoo.com | | Subject: | Re: Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | 18 Jan 2005 00:42:12 -0800 |
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| > >
> > Bostik Tensol #3 - From the specification it seemed this would
fulfil
> > the requirements perfectly, however in use it gives of the most
noxious
> > vapours.
>
> Bubbling is often controllable by degassing. Solvent-containing
> adhesives in spanning applications will give you shrinkage, bubbling,
> and usually crazing. You need 100% reactive, filled with dissolved
> polymer to limit shrinkage and boost viscosity.
>
> 1) Degassing. Stirred kettle under reduced pressure, preferably
> with a viewport. Reduce pressure and you will foam out dissolved
> air. The trick is to pulse the vacuum to control foaming and
mimimize
> loss of volatiles (the reactive monomer). Stir and reduce pressure.
> When it foams, seal. If the foam breaks under stirring, pull vacuum
> again until it foams. Seal, break foam, pull vacuum, seal... repeat
a
> few times.
>
> Many viscous liquids won't break foam with stirring. You can chance
> adding a breaker like Surfynol - *after* qualifying the bond in bench
> testing. Unless your engineers are really most sincerely absolutely
> positive the bond won't be compromised, silicone antifoams are risky.
> A good way to break tough foam is to stop stirring and crack to air.
> Slam it. Then pump down and stir (in that order - don't beat in more
> air) and do it again. When the dissolved gas gets lean the foam
won't
> support itself. 100 ml is easy. A gallon is no big deal. When you
> get big it can get slow and nasty.
>
> If it is a two-part system, degas separately, mix under reduced
> pressure, dispense. Atmospheric pressure is 760 torr. Water
> aspirator will pull 20 torr or less (cold water!). That is good
> enough if you can move enough gas volume. A mechanical pump will do
> the trick, of course, but you must trap the acrylic vapors or you
will
> seize the pump. Gas conductance varies as the *fourth* power of
> tubing radius. Evey tubing elbow and valve is a punch to the gut.
> Acrylic monomer is a fantastic plastic solvent. If you use plastic
> gas plumbing over long times, be able to inspect a section internally
> for degradation and deposition.
>
> 2) Standard amine cure epoxy turns yellow in light and with age.
> There are hydrogenated epoxies used in museum restoration that resist
> yellowing. Epoxies can craze acrylic. Reactive acrylics are
probably
> better here. Volatile acrylic monomers are blood toxins. If your
> folks get blued lips and/or fingernails, it's time to go home for the
> day - and don't do it again. Don't open yourself to O$HA terrorism.
> You may need positive ventilation masks in a production environment.
> It's generally cheaper to individually over-protect the workers than
> to rebuild the facility to minimum specs. Gloves, of couse -
> impermeable to acrylic monomer.
>
> 3) If outside safety certification comes your way, meet them at
the
> gate with your legal counsel and a videocam. Record every minute of
> the visit with credible witnesses present. Jackbooted State
> compassion is blunted by admissable evidence that survives
> cross-examination. A videotape cannot be cross-examined. You need
> trusted witnesses, too. "We are from the government. We are here to
> help ourselves to you."
Good tome on degassing, Uncle Al, all I would add is to preheat the two
components before separate degassing a little, it lowers viscosity and
helps the amine release dissolved CO2. You were right and I overlooked
the yellowing and shrinkage issues, thanks for the correction.
Your experience with the safety Nazis is consistent with mine, but
with the Feds lately I have seen they have less of a "gotcha" approach
and more of a cooperative, lets fix the problems approach. Also, in the
worst state, California, Gov. Terminator has called off the dogs, so to
speak, trying to save what little industry they have left, but this
last part is just what I've heard. What have others seen?-Jitney
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| | From: | jtnospam at yahoo.com | | Subject: | Re: Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | 17 Jan 2005 09:51:59 -0800 |
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grant wrote:
> I am currently trying to source an acrylic adhesive that fulfils the
> following requirements, and I would appreciate any product
suggestions.
> Thanks
> Grant
>
>
> Requirements:
>
> 1/ Must be structural, very high strength
> 2/ Must be gap filling
> 3/ Must be clear after setting (no colouration, no bubbles released
> from solvent evaporation)
> 4/ Must be unaffected by long term UV or Sunlight
> 5/ Must be permanently submersible in water (fresh and sea water)
> 6/ UV setting adhesives cannot be used due to nature of the join
> 7/ Must not give off extremely noxious vapours on setting
> 8/ Must be distributed in Europe
> 9/ Easily dispensed would be appreciated
>
>
> The product is intended to bond cast, extruded and formed acrylic
> together in a high-pressure, load bearing application. The intention
is
> to anneal the acrylic either before bonding or after. (Annealing and
> setting the adhesive at the same time - I would be interested to know
> some opinions on doing this together)
>
>
> I have currently tested some products, specific polymer adhesives
more
> than general adhesives. I have tested:
>
> IPS Weld-On #16 - seemed to fulfil the requirements except for the
> bubbles released from the solvent. I have tried cooling the
> solvent-based adhesives to 5deg =B0C before use to limit the bubbles
> formed, but the result was still unsatisfactory.
>
> IPS Weld-On #40/42 - has a yellow colour tinge.
>
> A 'self-mixed' adhesive of Bostik Extrufix with acrylic cuttings
> added to form a paste - seemed to fulfil the requirements except for
> the bubbles released from the solvent.
>
> Bostik Tensol #3 - From the specification it seemed this would fulfil
> the requirements perfectly, however in use it gives of the most
noxious
> vapours.
You need a solvent-free, two component system, try an epoxy. Google for
source, there are many compounders.-Jitney
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| | From: | Uncle Al | | Subject: | Re: Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | Tue, 18 Jan 2005 13:05:24 -0800 |
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| jtnospam@yahoo.com wrote:
>
> > >
> > > Bostik Tensol #3 - From the specification it seemed this would
> fulfil
> > > the requirements perfectly, however in use it gives of the most
> noxious
> > > vapours.
> >
> > Bubbling is often controllable by degassing. Solvent-containing
> > adhesives in spanning applications will give you shrinkage, bubbling,
> > and usually crazing. You need 100% reactive, filled with dissolved
> > polymer to limit shrinkage and boost viscosity.
> >
> > 1) Degassing. Stirred kettle under reduced pressure, preferably
> > with a viewport. Reduce pressure and you will foam out dissolved
> > air. The trick is to pulse the vacuum to control foaming and
> mimimize
> > loss of volatiles (the reactive monomer). Stir and reduce pressure.
> > When it foams, seal. If the foam breaks under stirring, pull vacuum
> > again until it foams. Seal, break foam, pull vacuum, seal... repeat
> a
> > few times.
> >
> > Many viscous liquids won't break foam with stirring. You can chance
> > adding a breaker like Surfynol - *after* qualifying the bond in bench
> > testing. Unless your engineers are really most sincerely absolutely
> > positive the bond won't be compromised, silicone antifoams are risky.
>
> > A good way to break tough foam is to stop stirring and crack to air.
> > Slam it. Then pump down and stir (in that order - don't beat in more
> > air) and do it again. When the dissolved gas gets lean the foam
> won't
> > support itself. 100 ml is easy. A gallon is no big deal. When you
> > get big it can get slow and nasty.
> >
> > If it is a two-part system, degas separately, mix under reduced
> > pressure, dispense. Atmospheric pressure is 760 torr. Water
> > aspirator will pull 20 torr or less (cold water!). That is good
> > enough if you can move enough gas volume. A mechanical pump will do
> > the trick, of course, but you must trap the acrylic vapors or you
> will
> > seize the pump. Gas conductance varies as the *fourth* power of
> > tubing radius. Evey tubing elbow and valve is a punch to the gut.
> > Acrylic monomer is a fantastic plastic solvent. If you use plastic
> > gas plumbing over long times, be able to inspect a section internally
> > for degradation and deposition.
> >
> > 2) Standard amine cure epoxy turns yellow in light and with age.
> > There are hydrogenated epoxies used in museum restoration that resist
> > yellowing. Epoxies can craze acrylic. Reactive acrylics are
> probably
> > better here. Volatile acrylic monomers are blood toxins. If your
> > folks get blued lips and/or fingernails, it's time to go home for the
> > day - and don't do it again. Don't open yourself to O$HA terrorism.
> > You may need positive ventilation masks in a production environment.
> > It's generally cheaper to individually over-protect the workers than
> > to rebuild the facility to minimum specs. Gloves, of couse -
> > impermeable to acrylic monomer.
> >
> > 3) If outside safety certification comes your way, meet them at
> the
> > gate with your legal counsel and a videocam. Record every minute of
> > the visit with credible witnesses present. Jackbooted State
> > compassion is blunted by admissable evidence that survives
> > cross-examination. A videotape cannot be cross-examined. You need
> > trusted witnesses, too. "We are from the government. We are here to
> > help ourselves to you."
>
> Good tome on degassing, Uncle Al, all I would add is to preheat the two
> components before separate degassing a little, it lowers viscosity and
> helps the amine release dissolved CO2. You were right and I overlooked
> the yellowing and shrinkage issues, thanks for the correction.
> Your experience with the safety Nazis is consistent with mine, but
> with the Feds lately I have seen they have less of a "gotcha" approach
> and more of a cooperative, lets fix the problems approach. Also, in the
> worst state, California, Gov. Terminator has called off the dogs, so to
> speak, trying to save what little industry they have left, but this
> last part is just what I've heard. What have others seen?-Jitney
The Left and the Right alternate excesses. Overall the country is a
miracle as long as it can both slosh and equilibrate. Alas, life is
about point values not averages. Our Gubernator is a gem, but he
can't be everywhere. I've never seen a soldier criticized for killing
enemy. Only the survivors can getcha. No survivors - combatants or
hostile witnesses. If you do not generate waste you need not dispose
of it afterward.
Choice starts at the lowest levels. Product is manufacture as well as
manufactured. Design for overall success starting at the start.
There will be more than enough surprises to keep you entertained as
the project matures to market - and warranty claims thereafter. "8^>)
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
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| | From: | David Zopf | | Subject: | Re: Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | Mon, 17 Jan 2005 17:26:09 GMT |
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"grant" wrote in message
news:1105978428.730047.7600@c13g2000cwb.googlegroups.com...
I am currently trying to source an acrylic adhesive that fulfils the
following requirements, and I would appreciate any product suggestions.
Thanks
Grant
Grant,
Speak with the fine technical service follks at Holdtite;
http://www.holdtite.com
sales@holdtite.com
Phone: (+44) 0191 491 4433
Good Luck,
R. David Zopf
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| | From: | Uncle Al | | Subject: | Re: Sourcing an Acrylic / Plexiglas / Perspex / PMMA adhesive | | Date: | Mon, 17 Jan 2005 10:12:14 -0800 |
|
|
| grant wrote:
>
> I am currently trying to source an acrylic adhesive that fulfils the
> following requirements, and I would appreciate any product suggestions.
> Thanks
> Grant
>
> Requirements:
>
> 1/ Must be structural, very high strength
> 2/ Must be gap filling
> 3/ Must be clear after setting (no colouration, no bubbles released
> from solvent evaporation)
> 4/ Must be unaffected by long term UV or Sunlight
> 5/ Must be permanently submersible in water (fresh and sea water)
> 6/ UV setting adhesives cannot be used due to nature of the join
> 7/ Must not give off extremely noxious vapours on setting
> 8/ Must be distributed in Europe
> 9/ Easily dispensed would be appreciated
>
> The product is intended to bond cast, extruded and formed acrylic
> together in a high-pressure, load bearing application. The intention is
> to anneal the acrylic either before bonding or after. (Annealing and
> setting the adhesive at the same time - I would be interested to know
> some opinions on doing this together)
>
> I have currently tested some products, specific polymer adhesives more
> than general adhesives. I have tested:
>
> IPS Weld-On #16 - seemed to fulfil the requirements except for the
> bubbles released from the solvent. I have tried cooling the
> solvent-based adhesives to 5deg °C before use to limit the bubbles
> formed, but the result was still unsatisfactory.
>
> IPS Weld-On #40/42 - has a yellow colour tinge.
>
> A 'self-mixed' adhesive of Bostik Extrufix with acrylic cuttings
> added to form a paste - seemed to fulfil the requirements except for
> the bubbles released from the solvent.
>
> Bostik Tensol #3 - From the specification it seemed this would fulfil
> the requirements perfectly, however in use it gives of the most noxious
> vapours.
Bubbling is often controllable by degassing. Solvent-containing
adhesives in spanning applications will give you shrinkage, bubbling,
and usually crazing. You need 100% reactive, filled with dissolved
polymer to limit shrinkage and boost viscosity.
1) Degassing. Stirred kettle under reduced pressure, preferably
with a viewport. Reduce pressure and you will foam out dissolved
air. The trick is to pulse the vacuum to control foaming and mimimize
loss of volatiles (the reactive monomer). Stir and reduce pressure.
When it foams, seal. If the foam breaks under stirring, pull vacuum
again until it foams. Seal, break foam, pull vacuum, seal... repeat a
few times.
Many viscous liquids won't break foam with stirring. You can chance
adding a breaker like Surfynol - *after* qualifying the bond in bench
testing. Unless your engineers are really most sincerely absolutely
positive the bond won't be compromised, silicone antifoams are risky.
A good way to break tough foam is to stop stirring and crack to air.
Slam it. Then pump down and stir (in that order - don't beat in more
air) and do it again. When the dissolved gas gets lean the foam won't
support itself. 100 ml is easy. A gallon is no big deal. When you
get big it can get slow and nasty.
If it is a two-part system, degas separately, mix under reduced
pressure, dispense. Atmospheric pressure is 760 torr. Water
aspirator will pull 20 torr or less (cold water!). That is good
enough if you can move enough gas volume. A mechanical pump will do
the trick, of course, but you must trap the acrylic vapors or you will
seize the pump. Gas conductance varies as the *fourth* power of
tubing radius. Evey tubing elbow and valve is a punch to the gut.
Acrylic monomer is a fantastic plastic solvent. If you use plastic
gas plumbing over long times, be able to inspect a section internally
for degradation and deposition.
2) Standard amine cure epoxy turns yellow in light and with age.
There are hydrogenated epoxies used in museum restoration that resist
yellowing. Epoxies can craze acrylic. Reactive acrylics are probably
better here. Volatile acrylic monomers are blood toxins. If your
folks get blued lips and/or fingernails, it's time to go home for the
day - and don't do it again. Don't open yourself to O$HA terrorism.
You may need positive ventilation masks in a production environment.
It's generally cheaper to individually over-protect the workers than
to rebuild the facility to minimum specs. Gloves, of couse -
impermeable to acrylic monomer.
3) If outside safety certification comes your way, meet them at the
gate with your legal counsel and a videocam. Record every minute of
the visit with credible witnesses present. Jackbooted State
compassion is blunted by admissable evidence that survives
cross-examination. A videotape cannot be cross-examined. You need
trusted witnesses, too. "We are from the government. We are here to
help ourselves to you."
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
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