Modified natural rubber glove with spent coffee grounds for prothesis arm cover

Abstract

In this research, we developed modified rubber gloves that could cover prosthetic arms manufactured from Fused Deposition Modeling (FDM) 3D printing. FDM can produce customized prosthetic arms that are lightweight and fit the individual needs of patients. Currently, the gloves used to cover prosthetic arms are made from flexible and soft material such as silicone or polyurethane. In these studies, were use natural rubber latex (NR) to produce rubber gloves, that enhance the physical appearance of the prosthetic arm, producing a similar color and detail to the patients arm. The glove color was improved by mixing with spent coffee grounds (SCG) to produce a similar color to that of natural human skin. Moreover, SCG was not only used as a color pigment, it also contains coffee oil that creates a glossy textured on the surface similar to silicone oil. The modification process of NR used a SCG dispersion solution mixed with NR. Rubber gloves were prepared by a dipping process and use sulfur vulcanization at 75 °C, for 2 h in a hot air oven. The specimens were characterization by physical (morphology, color parameter, and %swelling), mechanical (tensile test) and thermal properties. Furthermore, the SCG can be used as a filler in natural rubber due to rubber-filler interactions that improve the tensile strength of the rubber glove with the SCG particles having a good distribution in the rubber phase. The SCG can improve the ageing stability (under 70 °C and Fluorescent light) of the rubber gloves as represented by the color parameter and tensile properties. After ageing showed a small difference in color parameter and a slight decrease in the tensile properties when greater amounts of SCG was presented in the rubber phase. Moreover, this can increase the economic value of natural rubber and spent coffee grounds in Thailand.