Styrene-acrylonitrile etching

Sodium etch Sodium hydroxide Sanitizing melamine or urea polymer, polyolefin, polyethylene oxide, polystyrene, polysulfone, and styrene-acrylonitrile (SAN) Fluoroplastics and some polyesters Polystyrene, polyesters, polyamide, and polysulfone Homopolymer polyacetal Developed by... 

Effect of different components in multicomponent blends based on polyamide 6 (PA 6) and styrenic polymers. Addition of a reactive compatibilizer maleic anhydride grafted styrene acrylonitrile (SANMA) changed the matrix-dispersed particle structure of PA6/styrene acrylonitrile (SAN) to a cocontinuous one. Replacement of part of SAN by polybutadiene particles led to a coarse cocontinuous structure (PA6/acrylobutadiene styrene [ABS]), which was refined after compatibUizer addition. SEM of cut surfaces etched in different solvents. (A) PA6/SAN = 50/50 wt%, SAN etched in tetrahydrofurane (B) PA6/ABS = 50/50 wt%, PA6 etched in formic add (C) PA6/ABS = 50/50 wt%, SAN etched in tetrahydrofurane (D) PA6/SAN+SANMA, PA6 etched in formic add (E) PA6/ABS+ SANMA, PA6 etched in formic add and (F) PA6/ABS = 50/50 wt%, PA6 etched in formic add. (From S. H. Jafari, P. Potschke, M. Stephan, G. Pompe, H. Warth, and H. Alberts, Polymer 43,6985-6922,2002. With permission.)... 

Isopropanol vapor was used to dissolve the matrix in polymer blends [245]. Williams and Hudson [246] etched microtomed blocks of high impact polystyrene so that the rubber particles protruded from the matrix. Later, Kesskula and Traylor [130] removed rubber particles from Hire and ABS polymers by dissolving the matrix in a cyclohexane solution of osmium tetroxide and extracting the dispersed phase for SEM. Olefin particles were removed from impact modified nylon and polyester [6]. Selective etching of the polycarbonate phase with triethyl-amine in a mixture with styrene-acrylonitrile copolymer (SAN) revealed the nature of the blend [247]. 

Chemical reduction is used extensively nowadays for the deposition of nickel or copper as the first stage in the electroplating of plastics. The most widely used plastic as a basis for electroplating is acrylonitrile-butadiene-styrene co-polymer (ABS). Immersion of the plastic in a chromic acid-sulphuric acid mixture causes the butadiene particles to be attacked and oxidised, whilst making the material hydrophilic at the same time. The activation process which follows is necessary to enable the subsequent electroless nickel or copper to be deposited, since this will only take place in the presence of certain catalytic metals (especially silver and palladium), which are adsorbed on to the surface of the plastic. The adsorbed metallic film is produced by a prior immersion in a stannous chloride solution, which reduces the palladium or silver ions to the metallic state. The solutions mostly employed are acid palladium chloride or ammoniacal silver nitrate. The etched plastic can also be immersed first in acidified palladium chloride and then in an alkylamine borane, which likewise form metallic palladium catalytic nuclei. Colloidal copper catalysts are of some interest, as they are cheaper and are also claimed to promote better coverage of electroless copper. 

Acrylonitrile butadiene styrene Acetone 1. Abrasion. Grit or vapor blast, or 220-grit emery cloth, followed by solvent degreasing. 2. Etch in chromic acid solution for 20 min at 60°C. Recipe 2 for methyl pentene... 

Acidic, Cifvi) solutions may be used as cleaners or etchants for metals (e.g. Cu) and plastics, e.g. ABS acrylonitrile/butadiene/styrene. In the case of metals, the Cffvi) may be used in order simply to clean the metal, etch the surface or completely remove a metal coating. The etching of plastic substrates is a key step prior to metallizing epoxy based laminates during the production of printed circuit boards. 

Table 7.5 Composition of Etching Solution for Acrylonitrile—Butadiene—Styrene...

The choice of substrate can impact the chemical and etch resistance of a coated plastic part. Thin layers of paint (especially when thin) can be influenced by the hardness of the substrate. However, this does not generally impact the chemical resistance of clear-coated parts as measured in testing such as Jacksonville. Substrates that are sensitive to solvents such as acrylonitrile butadiene styrene (ABS) and polycarbonate/polybutylene terephthalate (PC/PBT) can be rapidly or slowly degraded when attacked with certain solvents or even basic materials. 

Among the various plastic materials used for chrome-plated parts, ABS (copolymer of acrylonitrile-butadiene-styrene) and PC/ABS (blends of ABS with polycarbonate) are most common. Nearly 85% of the total plated plastic surface area is based on ABS or PC/ABS. The technology for etching out the rubber particles from the ABS phase using an oxidative mixture of sulfuric and chromic acid has been widely used in the industry for nearly 40 years. The etched surface is subsequently activated using precious metal species, which is then followed by an electroless deposition of a thin layer of nickel or copper. In this marmer, the smface of the otherwise non-conductive plastic is rendered electrically conductive. Subsequently, multiple layers of different... 

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