Different applications require different materials. Dymax works on creating model formulas for rigid, tough, and flexible 3D printing resins that can assist users in all kinds of applications. Specific mechanical properties must be determined in order to mimic those of thermoplastic materials in multiple categories. It is important to determine physical requirements for the specific resin so model formulas for rigid, tough, and/or flexible materials can be identified. For example, in order to print successfully and with a good resolution, a low viscosity is a very important property.
Through the developments of model 3D printing formulas, there has been further research into manipulating the properties 3D printing materials provide. A new white paper by Dymax features a study that targets superior impact and temperature resistance properties in photopolymer-based 3D printing resins. The goal is to create resins that meet or exceed the capabilities of thermoplastic materials. Improvements in impact strength while maintaining a high Heat Deflection Temperature (HDT) can provide insight about how to replicate thermoplastic properties in 3D-printed materials. The data gathered in this white paper allowed for new developments in light-curing 3D printing processes. This information proves that it’s possible to improve both HDT and impact resistance simultaneously, rather than sacrificing one for the other.
Printability
Printability was a large part of this white paper study, as there are many limitations to the 3D printing process. Limitations include low formulation viscosities, limited light source intensities, and cure dynamics of the 3D printing process. To identify the best options for 3D printing oligomer development, the study explored improving impact resistance by modifying hard, highly crosslinked networks with flexible impact-modifying resins. A few experimental hard resins were tested both alone and together with several impact modifying materials in a model formula. These materials were categorized by functionality and molecular weight and included a range of backbone chemistries. The hard resin and impact modifier formulations with the best balance of HDT and impact resistant properties were subjected to additional testing to identify potential relationships to tensile strength and elongation.
The results have allowed Dymax to expand their knowledge of light-curing 3D printing processes and gain powerful insight into improving both HDT and impact resistance concurrently.