Two deliveries of black handles, said to be made of PA66
Measuring cell: DSC20
Pan: Aluminum standard 40 μl, pierced lid
Sample preparation: Disk cut from the center of the handles. Shipment A: 6.2 mg, shipment B: 8.3
DSC measurement: Heating from 50 to 300 C at 10 K/min
Atmosphere: Nitrogen, 50 cm3/min
In this particular case it was sufficient to check the peak temperatures: Shipment A: 271.8 C, therefore PA66; shipment B:231.7 C, therefore PA6.
The DSC melting peaks immediately showed that only shipment A was made of PA66. The high peak temperature indicates that it could be Bergamid A70B30. Shipment B is clearly made of PA6 and was therefore rejected.
The different types of polyamide can be distinguished by measuring their DSC peak temperatures. Checking the raw materials by DSC avoids complaints later on from the end user of the finished product. The time needed for a DSC run could be reduced to less than 10 minutes by using a higher heating rate, e.g. 20 K/min
PA6 and PA66, Mistaken Identity | Thermal Analysis Handbook No.HB230| Application published in METTLER TOLEDO TA Application Handbook Thermoplastics