Journal articles on the topic 'Acetone smoothing'

Fused deposition modeling (FDM) is an additive manufacturing technology where three-dimensional physical models are manufactured by layer-by-layer deposition. However, the layered surface built with FDM suffers from poor surface quality and dimensional accuracy even for basic part geometries. This proves to be unacceptable and not satisfactory for most general purposes with the consequence of a decreased value of the final product. Several methods for post-processing were proposed to achieve fine surface of manufactured components. In particular, for components manufactured with polylactic acid (PLA) the chemical post-processing with dimethyl ketone (acetone), named vapor smoothing process, seems to be very promising to significantly improve the surface roughness. Moreover, acetone has the main advantage to have a low cost, low toxicity and high diffusion rate. However, this polishing procedure may dissolve the outer surface of the parts affecting the structural reliability of the part. In this work, a novel device, consisting of a cylindrical chamber in Pyrex, is set-up for the vapor smoothing process with acetone. The system is designed to permit the injection of a gas containing acetone at different concentrations and at different operating conditions (temperature, contact time). The samples used for the test are truncheon design manufactured using different printer settings; each truncheon is built at inclination angles varying from 0° to 45° in step of 5°. The variation of the surface roughness was investigated using a confocal microscope Leica DCM3D, equipped with the software LeicaScan and LeicaMap.

3D printing is an additive manufacturing method that turns digital design into an actual product. A 3D-printed part sometimes requires post-processing to enhance its physical and mechanical properties. Acetone vapor polishing is one of those techniques which is highly beneficial in smoothing ABS 3D-printed parts. Previously, an acetone vapor polishing device has been developed which uses a mist maker. However, for a more efficient polishing method, an optimized vapor polishing device using heat has been fabricated in this study. To assess the efficiency of this device, the researchers test the dimensional accuracy, surface roughness, tensile strength, and impact strength of polished and unpolished ABS 3D-printed specimens. The findings showed that the surface smoothness of the polished cube specimens did not significantly alter its physical geometry. The tensile test reveals that the overall elasticity of the polished tensile specimen has increased significantly while the impact test also shows that the polished specimens have the capacity to sustain a resistive impact from a swinging pendulum. Thus, all testing procedures indicated that post-processing using the optimized vapor polishing device has improved the overall physical and mechanical properties of the polished specimens.

Computer-generated synthetic single-beam spectra and interferograms provide a means of comparing signal processing strategies that are employed with passive Fourier transform infrared (FT-IR) sensors. With the use of appropriate radiance models and spectrometer characteristics, synthetic data are generated for one-, two-, and four-component mixtures of organic vapors (ethanol, methanol, acetone, and methyl ethyl ketone) in two passive FT-IR remote sensing scenarios. The single-beam spectra are processed by using Savitsky–Golay smoothing and first-derivative and second-derivative filters. Interferogram data are processed by Fourier filtering using Gaussian-shaped bandpass digital filters. Pattern recognition is performed with soft independent modeling of class analogy (SIMCA). Quantitative models for the target gas integrated concentration-path-length product are built by using either partial least-squares (PLS) regression or locally weighted regression (LWR). Pattern recognition and calibration models of the filtered spectra or interferograms produced comparable results. Discrimination of target analytes in complex mixtures requires a sufficiently large temperature differential between the infrared background source and analyte cloud. Quantitative analysis is found to be possible only when the temperature of the analyte cloud is stable or known and differs significantly from the background temperature. Net analyte signal (NAS) methods demonstrate that interferogram and spectral processing methods supply identical information for multivariate pattern recognition and calibration.

AbstractThis study presents an experimental and numerical investigation to characterize the plume pattern of a high-aspect-ratio rectangular convergent/divergent nozzle with an aft deck in under-expanded conditions. The function of an aft deck is to shield the infrared signal of an exhaust plume at its strongest intensity located at the immediate downstream region of the nozzle exit. However, this practice may cause undesirable plume deflection, which needs to be reduced as much as possible. The nozzle pressure ratios ranged from 2 to 4, and the effect of the nozzle exit aspect ratio was examined using wall static pressure measurements and schlieren visualization for cold flows. The experimental setup involved a 3D-printed aft deck nozzle made of acrylonitrile butadiene styrene material, which underwent surface smoothing using acetone vapor. Numerical simulations were conducted using the commercial STARCCM$$^{\mathrm {+}}$$ + software to analyze static pressure ratio variations at the aft deck. The investigation revealed that a nozzle pressure ratio of 3 induced a downward plume deflection at aspect ratio values of 6.77 and 7.54, while an increased aspect ratio of 8.35 resulted in the horizontal ejection of the plume. Moreover, at an aspect ratio of 8.35, the plume was ejected horizontally for nozzle pressure ratios ranging from 2 to 4. At a nozzle pressure ratio of 4, the flow separated from the deck without reattaching, and the plume moved horizontally with minimal deflection. The findings suggest that a combination of a high aspect ratio and sufficiently high nozzle pressure ratio can effectively reduce plume deflection.

Key aspects of developing effective systems for the external reinforcement of building structures, made of composite polymer materials containing carbon fibers and no-bake polymer binders, ensuring shape formation in the temperature range of 15 - 40 °С no more than 24 hours, characterized by operability in the temperature range from minus 45 ° C to plus 60 ° C.. PCM-based SVA has a number of advantages compared to clips and metal profiles traditionally used for repairing building structures: the load-bearing capacity of the rods increases, the cost of the strengthening of load-bearing structures is reduced, and the seismic resistance of engineering structures is increased. In relation to composite SVA building structures, the following types of construction chemicals are used: primer, putty, adhesive, protective coating. The production of unidirectional tapes was carried out on a Dornier double rapier loom, modernized for processing carbon fibers. The results of experimental studies of the developed polymer binders and carbon reinforcing fillers are presented. It is shown that the developed materials can be successfully used to strengthen and repair engineering structures. The technological features of strengthening and repairing building structures with composite external reinforcement systems using the contact molding method and ready-made lamellas are described. Installation of composite clamps on vertical surfaces is carried out by fixing the canvas in the extreme position, followed by laying, smoothing and rolling along its length. Rolling is done from the middle to the edges. Before gluing the blanks, the lamellas are laid out on a work table (workbench) and thoroughly wiped with a rag moistened with acetone. Results of the large-scale implementation of these new materials and technologies in the construction industry are presented.

Lecithin is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues which are amphiphilic – they attract both water and fatty substances, and are used for smoothing food textures, emulsifying, homogenizing liquid mixtures, and repelling sticking materials. Lecithin’s are mixtures of glycerophospholipids including phosphatidylcholine, phosphatidyl-ethanolamine, phosphatidylinositol, phosphatidylserine, and phosphatidic acid. Lecithin can easily be extracted chemically using solvents such as hexane, ethanol, acetone, petroleum ether or benzene; or extraction can be done mechanically. Common sources include egg yolk, marine foods, soybeans, milk, rapeseed, cottonseed, and sunflower oil. It has low solubility in water, but is an excellent emulsifier. In aqueous solution, its phospholipids can form either liposomes, bilayer sheets, micelles, or lamellar structures, depending on hydration and temperature. This results in a type of surfactant that usually is classified as amphipathic. Lecithin is sold as a food additive and dietary supplement. In cooking, it is sometimes used as an emulsifier and to prevent sticking, for example in non-stick cooking spray. Soy Lecithin Improves Cholesterol Levels, it serves as a source of Choline, helps body deal with physical and mental Stress, relieves Menopause Symptoms. It may Boost Immunity, improve Cognitive Function, prevent Osteoporosis, and help prevent Cancer, Present study deals with determination of Lecithin from Egg Yolk, Soyabean seed, milk and sunflower oil Colorimetrically and FTIR study of Soy-Lecithin. Determination of Lecithin from Egg Yolk, Soyabean seed, milk and sunflower oil Colorimetrically involves preparation of Soy lecithin solution, Egg Yolk solution, Soyabean seed solution, Milk solution and Sunflower Oil solution. Different systems were prepared. Absorbance of standard Soy lecithin system was taken at different wavelength using ethyl alcohol as blank. And λmax was found which is 420 nm. Absorbance of standard Soy lecithin systems were taken at 420 nm and Calibration plot was prepared. Then absorbance of systems of Egg Yolk solution, Soyabean seed solution, Milk solution and Sunflower Oil solution were taken at 420 nm and concentration of Lecithin present in Egg Yolk, Soyabean seed, milk and sunflower oil were calculated from calibration plot. The method is simple, rapid and precise. FTIR spectra of Soy-Lecithin is obtained at room temperature by using an FTIR Spectrophotometer – Perkin Elmer – Spectrum RX-IFTIR. The spectra is collected in a range from 400 to 4000 cm^-1. Interpretation of FTIR Spectra of soy lecithin shows Presence of various functional groups such as C-H bending – Alkane, Aromatic compound; O-H Stretching – Alcohol, Carboxylic acid; C=O stretching – Esters and O=C=O stretching - Carbon dioxide.

AbstractThe understanding of the complex biomechanics of the knee is a key for an optimal implant design. To easily investigate the influence of prosthetic designs on knee biomechanics a rapid prototyping workflow for knee implants has been developed and evaluated. Therefore, different manufacturing technologies and post-treatment methods have been examined and overall seven different replica knee implants were manufactured. For evaluation, the manufacturing properties such as surface accuracy and roughness were determined and kinematic behaviour was investigated in a novel knee testing rig. It was carried out that PolyJet-Modelling with a sanded surface resulted in changed kinematic patterns compared to a usual CoCr-UHMWPE implant. However, fused deposition modelling using ABS and subsequent surface smoothening with acetone vapor showed the lowest roughness of the manufactured implants and only minor kinematic differences. For this reason this method constitutes a promising approach towards an optimal implant design for improved patient-satisfaction and long lifetime of the implant. Finally the workflow is not only limited to the knee.

The number, shape and position of NMR spectral lines depend on dynamic processes, and this creates certain difficulties in identification of pharmaceutical substances by NMR spectroscopy. The aim of the paper was to study instances of manifestation of intramolecular dynamic processes that affect identification of organic compounds by NMR, and to illustrate the potential of the methods used for their reduction, as well as associated problems.Materials and methods: 1H and 13C spectra of the following pharmaceutical substances: «buserelin acetate», «valsartan», «goserelin acetate», «iopromide», «clopidogrel hydrogensulfate», «omeprazole», «proroxan», «risperidone», «triptorelin acetate», and «enalapril maleate» were used to demonstrate negative effects of dynamic processes. The spatial structures of conformers were established by 1H-1H ROESY experiments. The quantum-chemical calculation of geometric and thermodynamic characteristics of different conformers was carried out by the PM3 method, and electronic characteristics—by the AM1 method with the help of the HyperChem software.Results: the authors analysed intramolecular dynamic processes which are most commonly encountered in expert work: pyramidal inversion of nitrogen in a heterocyclic compound (risperidone, proroxan, clopidogrel), rotation of molecular fragments around the amide bond (valsartan, iopromide, enalapril), prototropic rearrangements (buserelin, goserelin, omeprazole, triptorelin). The change in exchange rates was explained from the perspective of the change in the system of intra- and intermolecular nonvalent interactions.Conclusions: the use of traditional methods for increasing the rate of dynamic processes (increasing the temperature and changing the solvent) does not always eliminate the negative effects of intramolecular transformations. Methods of smoothing the spectral manifestations of dynamic processes have limited application due to strong intramolecular nonvalent interactions which prevent the conversion of the dynamic process rate into fast exchange. Experts and manufacturers should take into account the manifestation of dynamic processes during identification of pharmaceutical substances by NMR spectroscopy.

Polycrystalline ZnO thin films were prepared on silicon substrates using electrospray method with vertical setup. Water and ethanol were used as solvents for zinc acetate dehydrate and no postdeposition annealing was required for formation of ZnO. The influence of substrate temperature in the range of 150–250°C on surface morphology and roughness was studied by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and optical profilometry. An improvement of surface quality and smoothing of the films with temperature were obtained. X-ray diffraction measurements revealed that, at all investigated substrate temperatures, the films were polycrystalline with crystallites’ sizes decreasing with temperature. Besides, the preferred crystal orientation varies with the substrate temperature. The analysis of surface chemical composition and oxidation state was performed with X-ray photoelectron spectroscopy (XPS). It was shown that, at substrate temperature of 200°C, the deposited ZnO films were closest to the stoichiometric ones. In general, the films at 150°C were oxygen-deficient, while at other studied temperatures, the films had excess of oxygen more pronouncedly at 200°C. Spectral ellipsometric measurements confirmed that the structural disorder is the highest at 150°C and improves with temperature. Refractive indexes for films at 200°C and 250°C are almost the same, 1.97 and 1.93, respectively, at wavelength of 600 nm, while for the sample deposited at 150°C, the refractive index is substantially lower, 1.67. The optical band gap is slightly influenced by the substrate temperature: 3.27 eV at 150°C and 3.32 eV at 200°C.

Polycrystalline PbS thin films are being potentially used in different optical applications. Optimization of their optical response is always an area of interest. In the current paper, we report on the effect of deposition parameters such as concentration of reactants, dipping time and post deposition heat treatment on the grain size, structure, resistivity and optical response. Spontaneous reaction of lead acetate and thiourea in aqueous hydrazine hydrate was used for depositing PbS thin films on glass substrates. The deposition temperature was kept close to 100°C. Deposition of PbS films at such a high temperature and strong reactant concentrations has not been much emphasized in literature. The characterization of physical and optical properties was done by using XRD, SEM, DSC, dual beam spectrophotometer and two probe methods for resistivity measurement. Mean grain size and surface disorder increased with increasing reactant concentrations and dipping time. However, the effect was less prominent with increasing concentration of reactants than the deposition time. The structural features such as crystallite size, structure and film thickness directly correspond to photosensitivity and optical properties of thin films. Annealing affected the electronic properties considerably and lowered the band gap of material but did not cause any appreciable change in structure except smoothening of the grain boundaries to certain extent.

Purpose This study aims to present the optimization of parameters and effects of annealing and vapor smoothing post-processing treatments on the surface roughness and tensile mechanical properties of fused deposition modeling (FDM) printed acrylonitrile butadiene styrene (ABS). Design/methodology/approach Full-factorial test matrices were designed to determine the most effective treatment parameters for post-processing. The parameters for annealing were temperature and time, whereas the parameters for the vapor smoothing were volume of acetone and time. Analysis of surface roughness and tensile test results determined influences of the levels of parameters to find an ideal balance between mechanical properties and roughness. Findings Optimal parameters for vapor smoothing and annealing were determined. Vapor smoothing resulted in significantly higher improvements to surface roughness than annealing. Both treatments generally resulted in decreased mechanical properties. Of all treatments tested, annealing at 100 °C for 60 min provided the greatest benefit to tensile properties and vapor smoothing with 20 mL of acetone for 15 min provided the greatest benefit to surface roughness while balancing effects on properties. Originality/value Vapor smoothing and annealing of FDM ABS have typically been studied independently for their effects on surface roughness and material properties, respectively, with varying materials and manufacturing methods. This study objectively compares the effects of each treatment on both characteristics simultaneously to recommend ideal treatments for maximizing the balance between the final quality and performance of FDM components. The significance of the input variables for each treatment have also been analyzed. These findings should provide value to end-users of 3D printed components seeking to balance these critical aspects of manufacturing.

Abstract Additive manufacturing offers many benefits, yet it is confronted with the challenge of rough surfaces resulting from the appearance of seam lines on the printed parts due to the layer-by-layer printing process. This study investigates the effect of ultrasonic-assisted vapor smoothing on the surface roughness of 3D-printed ABS samples. The ABS samples were printed with an open-source FDM printer. The vapour smoothing process was conducted by applying acetone and altering the ultrasonic frequencies and times to 0 kHz, 10 kHz, and 20 kHz for the frequencies and 10 minutes, 20 minutes, and 30 minutes for the times. The surface roughness measurements were performed using a Mitutoyo SJ-301 surface roughness tester. The findings demonstrated enhancements in the quality of the surface, reduction in the visibility of layer lines, and improved surface smoothness for all the samples. From the ANOVA analysis, the average value of Ra for 30 kHz frequency is 2.57μm, which is better than 3.19μm for 10 kHz frequency. The manipulation of ultrasonic frequencies and exposure durations decreased surface roughness parameters, suggesting enhancement of the time to attain smoother surfaces. This work demonstrates the effectiveness of ultrasonic-assisted vapour smoothing as a feasible post-processing technique for enhancing surface quality in 3D-printed ABS-printed parts.

The surface roughness assessment of 3D printed parts with Fused Deposition Modelling (FDM) has been performed on Acrylonitrile Butadiene Styrene, Poly Lactic Acid, Polycarbonate, Nylon, Polypropylene, Co-polyester. Three different geometries were selected i.e., Cube, Cone and Strip to evaluate the effect of build geometry and material on the surface roughness of 3D printed parts of FDM technology. It has been revealed from the roughness measurements of cube and cone samples, that roughness values are higher as compared to strip sample and in almost the same range in the build direction irrespective of the shape. The variation of surface roughness as a function of nozzle temperature has also shown that it is also dependent on the nozzle temperature while keeping other parameters constant. The experiments on the improvement in the surface quality of FDM parts was also performed using chemical and physical methods. Tetrahydrofuran, Dichloromethane and Acetone were found compatible with polycarbonate to improve surface without compromising the geometrical shape. Similarly Acrylonitrile Butadiene Styrene had excellent response to Acetone vapour smoothing both in terms of surface roughness and part symmetry. The surface roughness of PLA was also improved after treatment with Tetrahydrofuran. Co-Polyester, although had good surface after treatment with Tetrahydrofuran and Dichloromethane, but the part symmetry was disturbed.

AbstractThis study aimed to identify and classify the type of plants used for tanning historical leathers using cost-effective Fourier transform infrared (FTIR) spectroscopy. The investigation was carried out on five plants (oak bark, sumac, valonia, tara, and gallnut) and four historical leather samples from book bindings dating back to the Qajar period. Tannin extraction from both plants and leathers was performed using acetone–water solvent, and the samples were then subjected to FTIR spectroscopy. Pre-processing of the spectra included baseline correction, smoothing, and normalization. Principal component analysis (PCA) was used to identify the source of tannins based on FTIR results. FTIR was found to provide a good separation of condensed tannins from hydrolysable ones. However, PCA analysis allowed for the separation and identification of the type of plant used for tannin extraction. The examination of historical leather samples revealed that the primary classification based on the type of tannin is possible, but accurate identification faces challenges due to structural changes and degradation over time. Graphical abstract

Figure S1: Laser microscope (x10) of the neck formation in the PP filament during the tensile test. Figure S2: Profile tensile force vs extension of the white ABS filament and the dumbbell shaped specimen prepared following the British Standard EN ISO 527-2:2012 (test conditions for molding and extrusion). Figure S3: Lose threads that can be seen in the filament made of 50 % virgin HDPE and 50 % virgin ABS upon rupture in the tensile testing. Figure S4: Tensile testing profiles for: (a) Commercial black ABS (8 replicates), (b) acetone smoothen white ABS (8 replicates), (c) virgin ABS (9 replicates), and (d) 10% white ABS + 90 % virgin ABS (10 replicates). Figure S5: Tensile testing profiles for: (a) 18 % white ABS + 82 % virgin ABS (10 replicates), (b) 35 % white ABS + 65 % virgin ABS (10 replicates), (c) 40 % white ABS + 60 % virgin ABS (15 replicates), and (d) 70 % white ABS + 30 % virgin ABS (10 replicates). Figure S6: Tensile testing profiles for: (a) 90 % white ABS + 10 % virgin ABS (10 replicates), (b) clogging ABS (10 replicates), (c) 50 % white ABS + 50 % black ABS (11 replicates), and (d) 50 % ABS+PC + 50 % black ABS (17 replicates). Figure S7: Tensile testing profiles for: (a) 50 % black ABS + 50 % HDPE (13 replicates), (b) 50 % virgin ABS + 50 % HDPE (10 replicates), (c) 50 % PP + 50 % PLA (21 replicates), and (d) 10 % PP + 90 % PLA (21 replicates). Figure S8: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for the white ABS: (a) unprocessed waste and (b) the 1.75-mm filament obtained with the melt-blend extrusion. Figure S9: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for the black ABS: (a) unprocessed waste and (b) the 1.75-mm filament obtained with the melt-blend extrusion. Figure S10: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for the ABS+PC: (a) unprocessed waste and in (b) the 1.75-mm filament obtained with the melt-blend extrusion. Figure S11: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for the PP: (a) unprocessed waste and in (b) the 1.75-mm filament obtained with the melt-blend extrusion. Figure S12: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for the virgin ABS: (a) unprocessed pellet and in (b) the 1.75-mm filament obtained with the melt-blend extrusion. Figure S13: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed at the temperature informed by the red line for: (a) white ABS filament @ 800 ºC; (b) commercial black ABS filament @ 800 ºC; (c) commercial black ABS filament @ 600 ºC; (d) commercial green ABS @ 600 ºC. Figure S14: Thermogravimetric analysis (green line) and differencing scanning calorimetry (blue line) performed up to 600 ºC (red line) for: (a) fresh HDPE; (b) HDPE stored at room condition for a year; (c) MidTemp purge; (d) PLA filament. Figure S15: Comparisons of the FTIR spectra of the HDPE and the Devoclean MidTemp purge. Figure S16: Laser microscope images (x5) of the rupture of the filaments of Commercial black ABS filament in the tensile test. Figure S17: Laser microscope images (x5) of the failure of the filaments of 50 % white ABS 50 % Black ABS in the tensile test. Figure S18: Laser microscope images (x5) of the failure of the filaments of10 % white ABS 90 % virgin ABS in the tensile test. Figure S19: Laser microscope images (x5) of the rupture of the filaments of 18 % white ABS 88 % virgin ABS in the tensile test. Figure S20. Laser microscope images (x5) of the failure of the filaments of 25 % white ABS 75 % virgin ABS in the tensile test. Figure S21: Laser microscope images (x5) of the failure of the filaments of 35 % white ABS 65 % virgin ABS in the tensile test. Figure S22: Neck formation in the filaments of 35 % white ABS 65 % virgin ABS during the tensile test. Figure S23: Laser microscope images (x5) of the rupture of the filaments of 40 % white ABS 60 % virgin ABS in the tensile test. Figure S24: Neck formation in the filaments of 40 % white ABS 60 % virgin ABS in the tensile test. Figure S25: Laser microscope images (x5) of the rupture of the filaments of 70 % white ABS 30 % virgin ABS in the tensile test. Figure S26: Laser microscope images (x5) of the failure of the filaments of 70 % white ABS 30 % virgin ABS in the tensile test. Figure S27: Laser microscope images (x5) of the rupture of the filaments of 90 % white ABS 10 % virgin ABS in the tensile test. Figure S28: Laser microscope images (x5) of the failure of the filaments of virgin ABS in the tensile test. Figure S29: Laser microscope images (x5) of the rupture of the filaments of 50 % HDPE and 50 % Black ABS in the tensile test. Figure S30: Laser microscope images (x5) of the failure of the filaments of 50 % HDPE 50 % Black ABS in the tensile test. Figure S31: Laser microscope images (x5) of the rupture of the striations of the filament of ABS+PC. Figure S32: Laser microscope (x10) of the formation of 2 fibers in the PP filament during the tensile test. Figure S33: Laser microscope images (x5) of the neck formation in the filaments of 50 % PP + 50 % PLA during the tensile test. Figure S34: Laser microscope images (x5) of the failure of the filaments of 10 % PP 90 % PLA in the tensile test. Figure S35: Laser microscope images (x5) of the neck formation in the filaments of 10 % PP 90 % PLA during the tensile test. Figure S36: Laser microscope images (x5) of the rupture of the filaments of PLA. Figure S37: Laser microscope images (x5) of the failure of the filaments of PLA (with neck formation). Figure S38: TGA/DSC profiles of the fraction of white ABS isolated with the acetone extraction: (a) 1^st supernatant, (b) 2^nd supernatant, (c) 3^rd supernatant, and (d) 4^th supernatant. Figure S39: TGA/DSC profiles of the fraction of white ABS isolated with the acetone extraction: (a) 1^st pellet, (b) 2^nd pellet, (c) 3^rd pellet, and (d) 4^th pellet. Figure S40: TGA/DSC profiles of the fraction of the white ABS soaked for 2 weeks in nitric acid (70 wt.%) with intermittent shaking. Figure S41: TGA/DSC profiles of the fraction of black ABS isolated with the acetone extraction: (a) 1^st supernatant, (b) 2^nd supernatant, and (c) 3^rd supernatant. Figure S42: TGA/DSC profiles of the fraction of black ABS isolated with the acetone extraction: (a) 1^st pellet, (b) 2^nd pellet, and (c) 3^rd pellet. Figure S43: TGA/DSC profiles of the fraction of ABS+PC isolated with the acetone extraction: (a) 1^st supernatant, (b) 2^nd supernatant, (c) 3^rd supernatant, and (d) 4^th supernatant. Figure S44: TGA/DSC profiles of the fraction of ABS+PC isolated with the acetone extraction: (a) 1^st pellet, (b) 2^nd pellet, (c) 3^rd pellet, and (d) 4^th pellet. Table S1: Extraction of the white ABS with nitric acid (70 wt. %) conducted for 2 weeks with intermittent shaking. Table S2: Extraction of the black ABS with nitric acid (70 wt. %) conducted for 2 weeks with intermittent shaking. Figure S45: (a) Material that was found among the plastic e-waste. (b) Metal parts that remained inside the melt-blend extruder and they needed to be purged with Devoclean MidTemp (polyethylene). Figure S46: Laser microscope images (x5) of the rupture of the filaments of clogging ABS 100 % in the tensile test. Figure S47: Laser microscope images (x10) of the failure of the filaments of Clogging ABS 100 % in the tensile test. Figure S48: (a) UltiMaker Cura visualization of the supportive material (blue color) that will be required to print the hard drive caddies with ABS. (b) Printed hard drive caddies with ABS. (c) Removal of the supportive material (30 % of the total ABS) from the hard drive caddies printed with ABS. (d) Proof that the small hard drive caddy fits for purpose. (e) Proof that the big hard drive caddy fits for purpose.

Fused Deposition Modeling (FDM) is one of the most commonly used Additive Manufacturing (AM) methods for converting 3D designs into physical models. The printing head melts the thermoplastic material and then extrudes the melted material through the extrusion nozzle layer by layer until the final 3D object is obtained. The build material used here is acrylonitrile butadiene styrene (ABS). The layer by layer addition of the material results in an uneven surface finish of the final product. Studies have shown that the post processing techniques like coating will have a positive impact on the surface finish as well as hardness. In this study, the specimen for the coating processes were printed as per the ASTM standards (ASTM D2240, ASTM D256) needed for mechanical tests. Different post processing techniques involving sputtering, spray painting and acetone dipping were carried out with a negligible change in specimen thickness. The samples were either coated with Copper, or dipped in acetone to smoothen the surface. These coated specimens were then tested for roughness & hardness and the results showed significant improvements. A comparison has been made between the results of different post processing techniques in order to determine the most suitable process.