Semester of Graduation
Master of Science (MS)
Acrylonitrile-butadiene-styrene (ABS) is a polymer that is widely used in many plastic products and is receiving new attention due to its use as a filament for fused deposition modelling (FDM) 3D printers. It has been shown to emit potentially dangerous volatile organic compounds (VOCs) when heated at temperatures used in the 3D printing process. Many new products are becoming available that contain various additives to the polymer matrix, which have an unknown effect on the emission profiles and rates. In this study a method is developed using a modified system for thermal diagnostic studies (STDS) to evaluate VOC emission from ABS polymer at low temperature 3D printing conditions. Samples of pure ABS and ABS filament containing carbon nanotubes (CNTs) were analyzed by this instrument at 200°C, 230°C, and 300°C, for 1-minute and 3-minute heating times, under pure nitrogen and 4% O2 carrier gases. The primary product detected for all reaction conditions was styrene. The majority of other detected VOCs were similar breakdown products of the polymer chain, such as ethylbenzene, α-methylstyrene, and isopropylbenzene, and their oxidized counterparts. The data suggests that the major effects of CNTs in the filament are to reduce emissions of styrene through the adsorption of monomers and to lower the amount of available matrix adsorbed oxygen. Oxygen in the carrier gas was shown to increase the proportion of oxidized products in the emission profile and decrease emissions of those without oxygen. The measured emission rates are consistent with studies that have analyzed VOC emissions from operating 3D printers, and do not identify significant risk associated with home use of the devices.
Lay, Dean, "VOC Emission Factors from 3D Printers - ABS (Acrylonitrile-Butadiene-Styrene) Type Filaments" (2019). LSU Master's Theses. 4850.