PC and a PC/ABS Blend Measured by DSC

Sample

PC, Makrolon 2405;
PC/ABS Blend Bayblend T85

Conditions

Measuring cell: DSC20

Pan: Aluminum standard 40 µl, pierced lid

Sample preparation: Disk cut from pellet

DSC measurement: First run 30 to 250 °C at 20 K/min to eliminate the thermal history, cooling at 20 K/min
                                    Actual measurement: heating from 30 to 250 °C at 20 K/ min

Atmosphere: Nitrogen, 50 cm³/min

Evaluation

In the table the glass transition temperatures are given as midpoints at 50% transition. 

From the ratio of the step heights of the PC glass transition (Δc_ppure/Δc_pmixture), it can be estimated that the mixture consists of two thirds PC and on third ABS.

Conclusions

Polycarbonate and some of its blends can easily be measured by DSC. Certain PC films (e.g. Makrofol) are semicrystalline and exhibit a small fusion peak around 235 °C. 

^{PC and a PC/ABS Blend Measured by DSC | Thermal Analysis Handbook No.HB249 | Application published in METTLER TOLEDO TA Application Handbook Thermoplastics}