transparent plastic with high yield 1

[metallergies]

What type of transparent or semi-transparent plastic/polycarbonate has the highest yield strength? Any and all answers appreciated!

 

[Demon3]

SAN and PMMA have the highest tensile strength at over 70MPa.

Chris DeArmitt PhD FRSC CChem

 

[metallergies]

Thank you Demon but i am looking for something with a higher fracture point than acrylic. Any more suggestions?

 

[patprimmer]

Yes

Tell us what you actually want then we can stop playing 20 guesses.

Regards
Pat
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[metallergies]

I want a transparent plastic with breaking strength as close as i can get to steel. imagine a hook w/ the diameter of a pencil. it needs to support around three-four hundred lbs. without fracturing. thank you

 

[patprimmer]

Without looking up datasheets polysulphone springs to mind as does Ultem. Both are very expensive and carry some yellow tint.

Can we have a clue as to the environment of use, hot, cold, humid, chemicals, food contact, etc etc.

Regards
Pat
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[Demon3]

Glass fiber will help your strength hugely. If you match the refractive index to that of your polymer then transparency will be retained.

Chris DeArmitt PhD FRSC CChem

 

[patprimmer]

I have seen successful meat hooks moulded in acetal. They will carry a pigs carcase at greater than the weights you state, but acetal is not transparent and the section was about twice as big as a pencil and had a T type cross section with all corners very well rounded off. For that project acetal was the only affordable plastic that had sufficient tensile, impact, food contact, creep and bearing properties in cool room conditions.

Chris. I am not convinced that there are glass fibres available that are suitable o reinforce a clear plastic that also have a similar RI. I would be very interested to find such a thing if it does exist.

Regards
Pat
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[Demon3]

Not sure either but I do know that glass has similar RI to common plastics, i.e. it's the same as PVC.

Chris DeArmitt PhD FRSC CChem

 

[cloa]

There is quite a lot of transparent FRP

http://www.eplastics.com/Plastic/Co...d-fiberglass-panels-2-1-2-corrugation-26-x-96

the first page of google is all roof panels but no reason it couldn't be other forms.

 

[metallergies]

The plastic will be used as a support hook, like the one in the link below. At 20 gauge, the support will need to hold around forty lbs. but the stronger the better. What is the best clear plastic/glass for this application?

http://www.solutioninn.com/engineer...s-are-applied-as-shown-to-hook-support.-using

 

[patprimmer]

metallergies

My Trend Micro Antivirus software blocked your site as dangerous.

Can you post pics on a safe site.

Without doing sums, I expect an amorphous grade of PET should do it.



Regards
Pat
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[metallergies]

Thank you, Pat. Here is another link. If i'm not mistaken, they use PET in plastic bottles. Do you believe that PET might "bend" too much for a support hook application?

http://www.google.com/products/cata...X&ei=5xSfTpufG4Xw0gHx_sGXCQ&ved=0CKMBEPMCMAk#

 

[btrueblood]

Can you post why the previous suggestions don't work?

 

[patprimmer]

Certainly the design you show in the latest link will be prone to bending in any plastic. A design more like the barb on a spear will work better as it keeps things much more in direct tension with much lower bending tendencies.

The design you now show requires exceptional tensile and flex mod as well as good impact.

Frankly that design is not really suited to plastics, especially the threaded part.

Regards
Pat
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[metallergies]

I'm having trouble finding the perfect mixture of brittleness and load bearing capability.
Pat, do you believe it's possible to add fibers w/ the same RI as a high quality grade of PMMA to negate the bending but still remain clear, as demon said?

 

[patprimmer]

It would seem possible, but I have never seen anyone actually do it and I cant imagine it has not been tried as the RI of various grades of glass strongly overlaps the RI of various plastics.

To successfully reinforce plastics several things need to happen

1) The matrix resin has to wet the fibre.
2) The matrix resin has to bond to the fibre.
3) The interface between the matrix resin and the glass must be durable in the environment of use.
4) The glass fibre needs to be strong and to have a high aspect ratio to be an effective reinforcment.

To obtain all four, coatings are normally used, so it requires a combination of a glass that can be drawn to a very fine fibre, is strong, will accept the correct coatings, is clear and has the same RI as the plastic and the same deal for the coating and all three components need to be durable in the application.

To begin an investigation would require a sizable market to justify commercially. I will make some inquiries. They might also involve Chris.

I doubt acrylic can be made to withstand more shock loading by the addition of glass.

Just how clear do you need this re discoloration and re haze and refraction as these will make a big difference.

Can you indicate the size of the market in tonnes per year.

Can you identify at least what continent or region you are in.

Regards
Pat
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