Molecular- and domain-level microstructure-dependent material model for nano-segregated polyurea
Multidiscipline Modeling in Materials and Structures
ISSN: 1573-6105
Article publication date: 18 November 2013
Abstract
Purpose
Polyurea is an elastomeric two-phase co-polymer consisting of nanometer-sized discrete hard (i.e. high glass transition temperature) domains distributed randomly within a soft (i.e. low glass transition temperature) matrix. A number of experimental investigations reported in the open literature clearly demonstrated that the use of polyurea external coatings and/or internal linings can significantly increase blast survivability and ballistic penetration resistance of target structures, such as vehicles, buildings and field/laboratory test-plates. When designing blast/ballistic-threat survivable polyurea-coated structures, advanced computational methods and tools are being increasingly utilized. A critical aspect of this computational approach is the availability of physically based, high-fidelity polyurea material models. The paper aims to discuss these issues.
Design/methodology/approach
In the present work, an attempt is made to develop a material model for polyurea which will include the effects of soft-matrix chain-segment molecular weight and the extent and morphology of hard-domain nano-segregation. Since these aspects of polyurea microstructure can be controlled through the selection of polyurea chemistry and synthesis conditions, and the present material model enables the prediction of polyurea blast-mitigation capacity and ballistic resistance, the model offers the potential for the “material-by-design” approach.
Findings
The model is validated by comparing its predictions with the corresponding experimental data.
Originality/value
The work clearly demonstrated that, in order to maximize shock-mitigation effects offered by polyurea, chemistry and processing/synthesis route of this material should be optimized.
Keywords
Acknowledgements
The material presented in this paper is based on work supported by the Office of Naval Research (ONR) research contract entitled “Elastomeric Polymer-By-Design to Protect the Warfighter Against Traumatic Brain Injury by Diverting the Blast Induced Shock Waves from the Head”, Contract Number 4036-CU-ONR-1125 as funded through the Pennsylvania State University. The authors are indebted to Dr Roshdy Barsoum of ONR for his continuing support and interest in the present work, and also to Professor G. Settles for stimulating discussions and friendship.
Citation
Grujicic, M., Snipes, J., Ramaswami, S., Galgalikar, R., Runt, J. and Tarter, J. (2013), "Molecular- and domain-level microstructure-dependent material model for nano-segregated polyurea", Multidiscipline Modeling in Materials and Structures, Vol. 9 No. 4, pp. 548-578. https://doi.org/10.1108/MMMS-10-2012-0014
Publisher
:Emerald Group Publishing Limited
Copyright © 2013, Emerald Group Publishing Limited