Additive Manufacturing of Natural Rubber
Problem statement
As consumer trends shift to favor environmentally conscious products and manufacturing practices, there has been a considerable push to develop sustainable high performing photocurable polymers for additive manufacturing processes with various application fields¹. Natural rubber latex (NRL) is a natural occurring polymer solution with 35% dry rubber content and 65% serum that is not rheologically suitable for 3D printing in its virgin form. To attain the minimum required viscosity for digital light synthesis (DLS) 3D printing, the NRL must be creamed with additives such as Potassium Lauryl Sulfate, and Irgacure 1173, however these additives have only been tested and delivered promising results on basic pH NRL solutions². NRL is currently used in more traditional industrial manufacturing processes, however the well known advantages of DLS 3D printing, such as rapid prototyping of complex geometries, customization, low volatile organic solvents, and low energy consumption, present a novel opportunity to marry a sustainable material with a more environmentally conscious manufacturing technology¹ ³. The Polymer Engineering Center at UW Madison and the group at EAFIT University, has tasked NRAM to develop a natural rubber latex formulation to be used for VAT polymerization 3D printing processes. First, the team will identify creaming blends for natural rubber latex at various concentrations on acidic pH NRL solutions that achieve suitable viscosity for DLS and SLA 3D printing (~60% dry rubber content per weight). Furthermore, the team will elect which UV curing agent will perform best with liquid natural rubber latex, and determine the required UV ray curing dosage and optimal times for specific blend formulations. Finally, NRAM will evaluate the resulting mechanical performance of the cured latex products by DLS 3D printing type IV tensile bars and conducting tests.
Team members
Emma Ralfs – leader
Caleigh Monfils – communicator
Lina M Perez – accountant
Hannah Granetzke – admin
Client
Professor Mónica Alvarez, University of EAFIT (Medellín)