BS ISO 6721-11:2019

What is ISO 6721-11 – Glass transition temperature of plastic about?  

The glass transition temperature (Tg) is an indicator of the transition from a hard and relatively brittle glassy state to a rubbery or viscous liquid state in an amorphous polymer or in amorphous regions of a partially crystalline polymer. Measured Tg values using instrumentation can vary because of material characteristics and/or the test set-up. 

ISO 6721 is a series of plastics which focuses on determination of dynamic mechanical properties. ISO 6721-11 specifies methods for determining a value of the glass transition temperature (Tg) from the dynamic mechanical properties measured during a linear temperature scan under heating conditions.  

Who is ISO 6721-11 – Glass transition temperature of plastic for? 

ISO 6721-11 on glass transition temperature of plastic is useful for: 

• Plastic manufacturing industries 
• Plastic testing laboratories 
• Plastic industries 
• Quality control personnel 

Why should you use ISO 6721-11 – Glass transition temperature of plastic?  

Dynamic mechanical analysis is used to determine the variation of the storage modulus, loss modulus and loss factor as a function of temperature and frequency. From these data, a value for the glass transition temperature is determined. 

ISO 6721-11 covers the use of dynamic mechanical analysis procedures, in the temperature scanning mode, to determine a value for the glass transition temperature of plastics. ISO 6721-11 provides you with an alternative procedure to the use of differential scanning calorimetry for this measurement.  

ISO 6721-11 specifications helps to determine the accurate value of glass transition temperature form the dynamic mechanical properties of plastic.  

What’s changed since the last update?  

BS ISO 6721-11:2019 supersedes BS ISO 6721-11:2012 which has been withdrawn. BS ISO 6721-11:2019 includes some technical changes with respect to BS ISO 6721-11:2012. These include: 

• The scope has been revised to specify suitable materials more accurately 
• Definitions of specific points in DMA curves have been extended 
• Reference to quality assurance purposes has been deleted 
• Several methods have been introduced for evaluation of the glass transition temperature 
• The procedure for the determination of heat dependent results has been revised 
• Curves of storage modulus, loss modulus, and loss factor have been added to the test report 
• The temperature calibration procedure has been revised 
• Additional temperature reference specimen for different loading modes has been introduced