Hard Squishy Material

[shoobaka1]

Looking for an "elastic" resin that is rigid. This material must be "hard" but compressable. After compression, this material must return to it's original shape. Injection molding grade. EtO sterilizable (3x). Radiopaque. Biocompatable.

Durometer > 80 Shore D.

TPE ?
TPU ?
TPV ?

 

[presso]

I think it might be hard to find a TPE or TPV with a hardness that high...

 

[TheAnswerGuy]

shoobaka1,

Check-out Santoprene by Advanced Elastomers
I believe that you will find most of the properties you seek within the material.

http://www.santoprene.com

It's your design and the type of compression set ("return to the original shape") that you experience or find acceptable, will be up to (you) the part designer.

Good Luck!

theanswerguy@tr-usa.com

 

[patprimmer]

I agree, "Santoprene" is the probably the best bet, but I thought it was a Thermo Plastic Vulcanate (TPV).

I think Advanced Elastomers have an exclusive on highly vulcanised TPVs (over 95% cross linked) due to patent protection, so they might be the only source.

Bayer and BASF could both supply info on PU, and Dupont and DSM could supply info on TPE.

I have no info on the EtO sterilizable (3x). Radiopaque. Biocompatable of any of these. You might need to get onto their technical departments to get this info. I expect most salesman will just give you a blank stare and platitudes.

You can enquire about the shore hardness from any salesman for these products or via the manufacturers websites as easily as I can. Your probably getting paid to do it. I'm not, so over to you.

Regards
pat

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[shoobaka1]

I am not the part designer. Solving this problem with a change in material properties would not be my approach.

I have sampled high Shore A TPE,TPU, and TPV. The customer would like something more rigid. My next step is to jump into the mid to high Shore D materials. I have only found this in a medical grade PSU. What is the breaking point between rigid and elastic ?

 

[patprimmer]

The difference between rigid and flexible is like difference between a mountain and a hill, or creek and river. There is no absolute value

Regards
pat

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[patprimmer]

Thermoplastic polyesters can be formulated from shore D high 30s to low 70s. It can be blended with PBT to give harder compounds.

TRY DSM and DUPONT AS SUGGESTED ABOVE

Regards
pat

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[shoobaka1]

"tecoplast" manufactured by Noveon seems to be getting close. Meets all of the criteria. High Shore D durometer.