metalman8357
Materials
Hi everyone,
Quick question here. I work for a company that owns a coating company used for construction. One of the products we offer is aliphatic polyurea, which can be painted onto concrete or steel as a sealant. We've had problems with the material failing on job sites, and we've sent out samples of our product to a third party lab to test tensile strength and % elongation. We report 450% elongation and 3200 psi on our spec. sheet, but the third party testing found 12% and a tensile strength of 3200 psi. Clearly something isn't right here so I have a few questions:
1.) My understanding is that aliphatic polyurea is a very flexible material and is considered an elastomer. 450% elongation seems more correct than 12%. I called the test lab and he said the material he received was already cured and very hard like a plastic. This doesn't seem right, but the tensile strength was there. Also, we test this to ASTM D2370 instead of ASTM D412...which one is more correct? Also, if we had a test sample that was 40 mils thick and pulled at 20 in/min vs. a 0.125" thick sample pulled at 2 in/min, should our % elongation still be pretty much the same value?
2.) Is aliphatic polyurea considered an thermoset elastomer or a thermoplastic elastomer?
3.) If we did in fact supply the correct material, how could it be possible to see 12% elongation. Is it possible for something to go wrong with the reaction to produce these results?
Any help would be much appreciated!
Quick question here. I work for a company that owns a coating company used for construction. One of the products we offer is aliphatic polyurea, which can be painted onto concrete or steel as a sealant. We've had problems with the material failing on job sites, and we've sent out samples of our product to a third party lab to test tensile strength and % elongation. We report 450% elongation and 3200 psi on our spec. sheet, but the third party testing found 12% and a tensile strength of 3200 psi. Clearly something isn't right here so I have a few questions:
1.) My understanding is that aliphatic polyurea is a very flexible material and is considered an elastomer. 450% elongation seems more correct than 12%. I called the test lab and he said the material he received was already cured and very hard like a plastic. This doesn't seem right, but the tensile strength was there. Also, we test this to ASTM D2370 instead of ASTM D412...which one is more correct? Also, if we had a test sample that was 40 mils thick and pulled at 20 in/min vs. a 0.125" thick sample pulled at 2 in/min, should our % elongation still be pretty much the same value?
2.) Is aliphatic polyurea considered an thermoset elastomer or a thermoplastic elastomer?
3.) If we did in fact supply the correct material, how could it be possible to see 12% elongation. Is it possible for something to go wrong with the reaction to produce these results?
Any help would be much appreciated!
