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Polymer selection

Polymer selection

Polymer selection

(OP)
Dear Forum memeber,

I have two questions:

1. Can one suggest me two polymers with known young's modulus between 2GPa - 15 GPa. And procedure or source to make it.

2. I am planning to make PMMA but not able to find the right curing temp. or procedure on internet. I have PMMA powder and toluene. I know I have to first disolve the PMMA in toluene, but, don't know the right curing tempreture.

Any comments??

Best,

Dhwajal

RE: Polymer selection

Yikes!

You can search all polymers by modulus for free at www.matweb.com

Unfilled polymers tend to top out around 3 GPa (polystyrene and SAN are two). For higher than that you're looking at adding fillers in most cases.

Making PMMA is usually a two step process because if you do it in one step the heat build up is too high and dangerous. First you make a prepolymer, then let it cool, then do the rest of the cure. I don't know the details though. You will have a lot of work to do in order to remove all that toluene.

Chris DeArmitt PhD FRSC CChem

www.phantomplastics.com
Consultant to the plastics industry

RE: Polymer selection

This sounds very academic. Are you a student.

As stated by others, PMMA can be cast from pre-polymers. That is how they make cast PMMA sheet. It must be carefully controlled as to little heat will not fully cure and to much will boil the pre-polymer and cause at least the pre-polymer to boil and create bubbles and at worst a fire or explosion.

 

Regards
Pat
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RE: Polymer selection

(OP)
Thanks..for replies and alerts!! I will be carefull. I will look for suitable fillers in to match desired modulus.

P.S. Well ...I am mechanical engineer (and not specialist of this field) and want to test some polymers. Hence posted on this forum.  

RE: Polymer selection

If you an engineer, do not attempt to make PMMA. That's a chemist's job for safety reasons.

You'd be better off curing some epoxy prepreg for example. Less likely to explode or gas yourself.

Chris DeArmitt PhD FRSC CChem

www.phantomplastics.com
Consultant to the plastics industry

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