Reprocessing of chromed ABS parts with chemical pickling and new chrome plating

Abstract

In this work, chrome-plated acrylonitrile-butadiene-styrene (ABS) parts containing defects in the deposited metal layer were pickled up to two times in hydrochloric and nitric acid under different immersion times. The influence of pickling on the properties of ABS was evaluated by thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopyattenuated total reflection (FTIR-ATR), scanning electron microscopy, atomic force microscopy, and roughness. The pickled parts were again chromed and evaluated by visual inspection and adhesion. The metallic layer was removed and a slight yellowing of the samples surface with the increase of pickling time. There were no significant changes in the thermal behavior of the material. Some of the components of ABS were removed, as evidenced by the reduction of the absorption peaks intensity in FTIR-ATR, by the increase of roughness and presence of pores on the surface. With the increase of the immersion time and the number of pickling, there was the formation of pores with larger sizes and decrease in roughness, making metal-polymer adhesion difficult. Only one pickling, under immersion time of 30 min, was adequate for the removal of the metallic layer, allowing new chrome plating. V C 2017Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46131.

Effect of Swelling of Chemical Reagents and the Sulfuric-Chromic Acid Bath on Surface Texturizing of Poly(Acrylonitrile-Butadiene-Styrene)

“…ABS metallized pieces even can be reprocessed by chemical pickling. 5 The surface of the piece has to be conditioned so that an excellent adherence exists between the foil and the substrate. With this purpose, in the Electroless process, there is the etching stage, which creates favorable conditions to carry on the surface metallization in a correct way and has the desired adhesion.…”

Recycling by injection and chrome plating of acrylonitrile–butadiene–styrene parts pickled in hydrochloric and nitric acids

“…1,5,7,8 Usually, due to inadequate operational control and the presence of impurities in the baths of chemical and rinsing solutions, defects can occur in the deposited metal layer, generating a scrap index of approximately 10%. 9,10 The most recurring defect of the chroming plating is the incomplete deposition of the metal layer, followed by scratches, water spots, porosity, oxidation, and bubbles. 10 The presence of defects leads to the reprobation of the parts in quality control, because they do not present a uniform surface finish on the surface, according to requirements of the customers and standards specified by the galvanic companies.…”

“…9,10 The most recurring defect of the chroming plating is the incomplete deposition of the metal layer, followed by scratches, water spots, porosity, oxidation, and bubbles. 10 The presence of defects leads to the reprobation of the parts in quality control, because they do not present a uniform surface finish on the surface, according to requirements of the customers and standards specified by the galvanic companies. Usually, the refuse parts are subjected to physical blasting by sandblasting or chemical pickling by immersion in hydrochloric and nitric acids (sulfochromic solution) to remove the metallic layers.…”

KMnO4‐system etching process and electroless nickel plating on ABS

“…Conventional electroless plating on ABS process can be divided into two important steps: pretreatment and metal plating. The available process for pretreating ABS involves etching, neutralization, and activation . The traditional chromic anhydride‐sulfuric acid etching system can produce plating layers with excellent surface quality in industrial production; however, using hexavalent chromium causes environmental pollution.…”

“…The available process for pretreating ABS involves etching, neutralization, and activation. [15,16] The traditional chromic anhydride-sulfuric acid etching system can produce plating layers with excellent surface quality in industrial production; [17] however, using hexavalent chromium causes environmental pollution. Thus, studies on economical processes have been the subject of interest for researchers over many years.…”