B100 Bonding Issue

B100 Bonding Issue

A customer called in and said that they were having issues with the Santoprene 8211-55B100 bonding to a polycarbonate substrate. The customer told me that there was no bond anywhere on the part, even at the gate. This was odd, as the expected bond strength (according to TL 01101 Injection Molding of Santoprene Thermoplastic Vulcanizate (TPV) 8211-55B100) is about 29.0 pli (5.1 kN/m). After discussing the processing parameters, I asked him to send in a sample part which was having the issues. The customer sent in a part. It looked as if there was a mix-up at the molder and Santoprene™ brand TPV 8211-55 was used. After some exams, I decided to cut off a piece of the elastomer and drop it in water, since the specific gravity of Santoprene™ brand TPV 8211-55 is 0.93 while the specific gravity of Santoprene™ brand TPV 8211-55B100 is 1.04, as seen in the product data sheets for these grades. The sample piece floated which showed that the elastomer was not Santoprene™ brand TPV 8211-55B100. The customer was able to order some bags of the correct material and have it shipped directly to the molder to fix the problem.

Posted on 2008-04-17 1:00 PM