Thank You for Asking.

We often receive great questions about molding with Eastman medical grade polymers and are always glad to provide answers and more information. Here is a response to a recent query from our inbox:
“What is the heat deflection temperature for Eastman MXF221 copolyester?”
Heat deflection temperature (HDT) is the temperature at which a polymer or plastic deforms under a specified load. The HDT of our latest offering, Eastman MXF221 copolyester, is outlined here.
Thermal properties
Deflection temperature  
  0.455 MPa (66 psi) ASTM
D 648 
94°C (201°F)
  1.82 MPa (264 psi) ASTM
D 648
83°C (181°F)
MXF221 is a biocompatible, fully compounded medical grade polymer that is uniquely suited for medical devices and electronic device housings. Developed from Eastman Tritan copolyester, MXF221 offers superior chemical resistance to stringent disinfectants and drugs, improved durability, and greater longevity.
Thermal control is critical for injection molding. Keeping temperatures cooled below the HDT of MXF221 helps ensure successful demolding with no dragging or sticking of parts. Preparing a cooling strategy early in the tool design process can pay big dividends in cycle time and processability.
For more information on MXF221’s properties, check out its product data sheet.