Design of Polymers for 3D Printing via Non-equilibrium Molecular Dynamics Simulation
Abstract
3D printing has recently become commonly employed as a versatile method of manufacturing complex and customizable components. It has widespread importance to the development of complex and specialised structures on scales from single-part synthesis to large-scale manufacturing. Key to the success of 3D printing for a particular application relies on selection of optimal materials and method of printing. Polymers form highly versatile, low density materials that are commonly used in 3D printing. Their use in fused deposition modeling will be the focus of this project. During the 3D printing process, the applied temperature and resultant temperature gradients, nozzle shape and size, extrusion pressure, and melt polymer flow rate and flow-dependent viscosity will be important. These conditions and the properties of the polymer, with any additives need to be optimized simultaneously to provide desired results. Experimental study of such properties can be expensive and time-consuming, computer simulations can offer a versatile and cost-effective way. Standard equilibrium simulation methods are ill-suited when highly non-equilibrium processing conditions lead to long relaxation times, making determination of key properties such as viscosity prohibitively computationally expensive. In addition, properties of non-Newtonian melts vary with driving force placed on them, and equilibrium results cannot provide good estimates under those conditions. We propose using non-equilibrium molecular dynamics simulation methods to determine polymer melt properties that are anticipated to be suitable for printing. Equilibrium and nonequilibrium methodologies will be compared and developed for polymers of various structure and degree of cross-linking. The change in extruded polymer properties will be quantified and used to enhance understanding of structure-property relationships and assist in determining the best approach for optimisation of 3D printing conditions.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 28, 2017
- Source ID
- FA23861714005
Entities
People
- Debra Searles
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Queensland