Dynamic Mechanical Analysis Duncan Price IPTME, Loughborough University © Copyright:...

Dynamic Mechanical Analysis

Duncan PriceIPTME, Loughborough University© Copyright: D.M.Price@lboro.ac.uk (2006)

mechanical testing

dynamic mechanical analysis

relationships

test configurations

Rubbery plateau is related to Me between cross-links or entanglements

Tll in some amorphous polymers

Tm = melting (1)

For thermosets, no Tm occurs

Rubbery plateau (2)

In semicrystalline polymers,a crystal-crystal slip, T* occurs

For purely crystalline materials, Tg occurs

Tg is related to molecular mass up to a limiting value

transitions are often related to the toughness

typical behaviour

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.