An Exploratory Study on the Development of Sargassum Algae-Based Biodegradable Polymer Composites Via Selective Laser Sintering
Board Location: #93
Discipline: Nanoscience or Materials Science
Subcategory: Materials Science
Session: 1
Stephanie Garcia - Polytechnic University of Puerto Rico
As a direct effect of climate change and agricultural runoff seeping into the Amazon River, tons of brown macroalgae known as Sargassum, have been accumulating on shores throughout the South Coast of North America and the Caribbean region since 2011. These unprecedented annual events have been detrimental not only to marine ecosystems but also to the human health and economy of coastal communities located in some U.S. territories and states. Despite the negative impact of the brown tide, Sargassum has the potential of being a valuable source for multiple industries including among others, cosmetics, fertilizers, and civil construction materials. However, the whole Sargassum biomass has not been explored as a biomaterial for applications in additive manufacturing (AM), a growing technological field that (1) is changing the way how things are made, and (2) is expected to be an engine of America’s economy and national security in the near future. Therefore, the main goal of this research project is to explore the use of Sargassum/biopolymer composite micro-powders for selective laser sintering (SLS) 3D printing, one of the most promising techniques in the AM field. If successful, this work could help expand the range of materials suitable for processing by SLS, which is very much dominated by polyamide 12 (nylon PA12). Unfortunately, nylon has been the subject of debate at times, especially as concerns its sustainability.To achieve the project goal, the team has established three main objectives: (1) fabricate Sargassum/biopolymer composite micro-powders having algal biomass contents ≥ 30wt%, and excellent flowability for SLS, (2) fabricate Sargassum/biopolymer composite specimens via SLS using the obtained powders, and (3) study the effects of Sargassum content and key SLS printing parameters on the microstructure and mechanical properties of the specimens.Regarding the first objective, Sargassum/biopolymer composite micro-powders are fabricated via wet granulation as follows: Firstly, a suitable amount of dried Sargassum is pulverized via ball milling and then incorporated into an aqueous biopolymer/binder dispersion using a planetary mixer. The resulting brown paste is then dried in an oven overnight to obtain a cake. Next, this dried cake is cut into pieces, which are then fed into an oscillating granulator to obtain a fine powder. Lastly, the fine powders are characterized via optical microscopy, and angle of repose.To fabricate the 3D printed specimens, the powders are fed into a SLS machine from Sintratec®, where the printing process takes place under controlled conditions. In addition, the team plans to evaluate the effect of some key parameters on the mechanical properties and microstructure of the specimens. The printing parameters to be changed are the laser scan speed, layer thickness, and hatching spacing. In the case of the specimens’ properties, these will be evaluated via tensile and flexural tests, optical microscopy, and SEM.Acknowledgement – This work was supported by an NSF award from the Division of Undergraduate Education No. 2224801.
Funder Acknowledgement(s): NSF - Division of Undergraduate Education
Faculty Advisor: Dr. Omar Movil, omovil@pupr.edu
Role: It was an independent research. My tasks included: assembling and calibrating the Sintratec® SLS equipment, mixing and granulating the powder mixtures, characterizing the powder's flowability and morphology, and printing the specimens for future work on SEM microstructure characterization and mechanical property testing.