Dymax is creating solutions that allow photopolymer-based 3D printing resins to meet or exceed the capabilities of thermoplastic materials such as polycarbonate or ABS, targeting superior impact and temperature resistance properties. The goal is improvements in impact strength while maintaining a high Heat Deflection Temperature (HDT).
Stronger UV-curable materials with high HDTs are generally low in impact resistance, being more inflexible or brittle due to a high degree of cross-linking in their molecular composition. On the other hand, high molecular weight materials with low crosslink density typically have a low HDT or are too high in viscosity to properly 3D print. To solve this persistent problem and achieve advancement in balancing these properties, chemists need to determine the best formulation approach to attain this balance of properties within a UV-cured polymer network.
To identify the best options for 3D printing oligomer development, Dymax explored one concept for improving impact resistance by modifying hard, highly crosslinked networks with flexible impact-modifying resins. Dymax tested three experimental Hard Resins (HR) both alone and together with several Impact Modifying (IM) materials in a model formula. These materials were categorized by functionality and molecular weight, and included a range of backbone chemistries.
As Dymax researches and develops materials that balance HDT and impact resistance, we also must consider the limitations of the 3D printing process, including low formulation viscosities, limited light-source intensities, and cure dynamics of the 3D printing process. Formulators must also balance the need to achieve fast cure speed with the desire to minimize part shrinkage in order to achieve excellent print resolution and dimensional stability.
The formulations of HR/IM combinations with the best balance of impact resistance and HDT properties were subjected to additional testing to identify potential relationships to tensile strength and elongation. Materials with lower functionalities and molecular weight showed higher tensile strengths and somewhat reduced elongation. In some cases, the HR materials are able to be toughened through the IM modification with an increase in elongation as well as a constant or increased tensile strength.
The data gathered in testing several urethane (meth)acrylate resins has allowed Dymax to expand the reach of light-curing 3D printing processes and gain powerful insight into improving both HDT and IM simultaneously, rather than simply sacrificing one for the other. As industry leaders in the chemistry, mechanical systems, and formulation expertise needed to provide total solutions to our 3D printing clients, Dymax will apply these learnings to continue to push our understanding and development even further. Download our new white paper.
Discuss this article and more on the 3DPrintBoard or comment below to tell us what you think.
You May Also Like
3D Printing for Nerve Regeneration: Gelatin Methacrylate-Based Nerve Guidance Conduits
Chinese researchers delve deeply into tissue engineering, releasing the findings of their recent study in ‘3D printing of gelatin methacrylate-based nerve guidance conduits with multiple channels.’ While there have been...
3D Printing: Successful Scaffolds in Bone Regeneration
In ‘Comprehensive Review on Full Bone Regeneration through 3D Printing Approaches,’ the authors review new developments and solutions in tissue engineering for the formation of cells, as well as proposing...
3D Bioprinting Soft Actuators: Multiple Materials & Topology Optimization
In the recently published ‘Effects of Topology Optimization in Multimaterial 3D Bioprinting of Soft Actuators,’ international researchers delve further into the fabrication of soft robotics, bordering on the 4D as...
3D Printing News Briefs, May 14, 2020: DP Technology, Danish Healthtech, ORNL
We’re starting with software in today’s 3D Printing News Briefs, then moving on to a healthcare webinar and a 3D printed nuclear reactor. DP Technology is releasing new AM software...
View our broad assortment of in house and third party products.