PPs versus shear rate and temperature

Melt flow Index (MFI), melt flow rate (MFR) [Pg.171]

Dynamic mechanical testers apply a small sinusoidal stress or strain to a small sample of the polymer to be examined and measure resonant frequency and damping versus temperature and forced frequency. Instrument software computes dynamic storage modulus (G ), dynamic loss modulus (G ) and tan delta or damping factor. Measurements over a wide range of frequency and temperature provide a fingerprint of the polymer with sensitivity highly superior to DSC. [Pg.171]

One must remember that static methods like DSC and dynamic methods such as DMTA lead to very different data for the same characteristics, such as glass transition. [Pg.171]

Thermal analysis techniques (DSC,TGA, DMTA...) operating on mini or micro samples can detect pinpoint heterogeneities in final parts that bulk analysis methods such as rheom-etry are unable to do. Transient variations of moulding parameters, local design mistakes, internal stresses that influence the properties of the final product, notably impact behaviour, dimensional stability, warpage. .. can be displayed. [Pg.171]

The TPEs are often tested with elastomer standards some thermoplastics and TPEs are used as adhesives. Sometimes PE and more rarely PVC are crosslinked. Consequently, the following standards, while mainly concerning thermoplastics and composites, also include adhesives and elastomers. [Pg.172]

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