Measurement and Modelling of Chemical Shrinkage of Thermoset Composites


Article Preview

Knowledge of resin chemical shrinkage is crucial for the determination of residual strains, stresses and warpage of composite parts during curing. Shrinkage measurement is more accurate on several millimetre thick samples. However, in that case thermal properties of resin and the strong coupling between thermoset chemical reactions (generally rapid and strongly exothermal) and thermal fields lead to non-negligible thermal and curing gradients in the piece. It is then necessary to take these variations into account to have an accurate description of the shrinkage. In the present study, a home built device "PVT-α" mould is used to measure the volume variation of vinylester resin and associated composites during the curing and then shrinkage is identified by considering these gradients. The results demonstrate that a linear evolution of the shrinkage with conversion degree is a good model to describe the chemical effect on the global volume behavior of the piece. The contribution of chemical and thermal effects on volume curve is quantified.



Key Engineering Materials (Volumes 504-506)

Edited by:

M. Merklein and H. Hagenah






Y. Nawab et al., "Measurement and Modelling of Chemical Shrinkage of Thermoset Composites", Key Engineering Materials, Vols. 504-506, pp. 1129-1134, 2012

Online since:

February 2012




[1] C. Li, K. Potter, M.R. Wisnom, G. Stringer, In-situ measurement of chemical shrinkage of MY750 epoxy resin by a novel gravimetric method, Composites Science and Technology, 64 (2004) 55-64.

DOI: 10.1016/s0266-3538(03)00199-4

[2] N. Boyard, M. Vayer, C. Sinturel, R. Erre, D. Delaunay, Modeling PVTX diagrams: Application to various blends based on unsaturated polyester—Influence of thermoplastic additive, fillers, and reinforcements, Journal of Applied Polymer Science, 92 (2004).

DOI: 10.1002/app.20312

[3] J.V. Beck, B. Blackwell, C.S. Clair, Inverse Heat Conduction, Wiley–Interscience, New York (1985).

[4] S. David, Thermal conductivity of insulations using guarded hot plates, including recent developments and sources of reference materials, Measurement Science and Technology, 12 (2001) R89.

DOI: 10.1088/0957-0233/12/12/201

[5] J.L. Bailleul, D. Delaunay, Y. Jarny, Determination of Temperature Variable Properties of Composite Materials: Methodology and Experimental Results, Journal of Reinforced Plastics and Composites, 15 (1996) 479-496.

DOI: 10.1177/073168449601500503

[6] J. -P. Pascault, R.J.J. Williams, H. Sautereau, Thermosetting Polymers, 4th ed., Marcel Decker Inc., (2002).

[7] Y. Nawab, N. Boyard, V. Sobotka, P. Casari, F. Jacquemin, A Device to Measure the Shrinkage and Heat Transfers during the Curing Cycle of Thermoset Composites, Advanced Materials Research, 326 (2011) 19-28.

DOI: 10.4028/

[8] N. Boyard, A. Millischer, V. Sobotka, J.L. Bailleul, D. Delaunay, Behaviour of a moulded composite part: Modelling of dilatometric curve (constant pressure) or pressure (constant volume) with temperature and conversion degree gradients, Composites Science and Technology, 67 (2007).

DOI: 10.1016/j.compscitech.2006.07.004

[9] J. l. Bailleul, Optimisation du cycle du cuisson de pièces épaisses en matériau composite. Application a un préimprégné résine époxide/ fibres de verre, in, PhD thesis, Université de Nantes, (1997).

[10] C.S. Chern, G.W. Poehlein, A kinetic model for curing reactions of epoxides with amines, Polymer Engineering & Science, 27 (1987) 788-795.

DOI: 10.1002/pen.760271104

In order to see related information, you need to Login.