Transcript Dynamic Mechanical Analysis

Dynamic Mechanical Analysis
Duncan Price
IPTME, Loughborough University
© Copyright: [email protected] (2006)
mechanical testing
dynamic mechanical analysis
relationships
test configurations
typical behaviour
For purely crystalline
materials, Tg occurs
b transitions are often
related to the toughness
Tg is related to molecular mass
up to a limiting value
In semicrystalline polymers,
a crystal-crystal slip, Ta* occurs
Rubbery plateau (2)
Rubbery plateau is related
to Me between cross-links
or entanglements
Tll in some
amorphous
polymers
For thermosets,
no Tm occurs
Tm = melting (1)
polycaprolactone
impact resistance in nylon
material specification
thermoset cure
determination of Tg
effect of plasticiser
stress relief
PET
effect of frequency
frequency domain
frequency master curve
effect of molecular weight
gellation of polymer solution
thermoset curing
Gillham-Enns or TTT diagram
recommended reading
M. Reading and P.J. Haines; “Thermomechanical, dynamic mechanical and associated
methods” in; P. J. Haines; “Thermal methods of analysis: Principles, Applications and
Problems” Blackie, London (1995) pp.123-160.
K.P. Menard; “Dynamic Mechanical Analysis: A Practical Introduction to Techniques and
Applications”, CRC Press, Boca Raton (1999)
D. M. Price, “Thermomechanical and Thermoelectrical Methods”, in P.J. Haines (ed.)
Principles of Thermal Analysis & Calorimetry, ch. 4, Royal Society of Chemistry,
Cambridge (2002) pp. 94-128.