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SEM micrograph of ABS (1); PVC (2); PVC/ABS 20/80 blends (3); PVC/ABS 40/60 blends (4); and PVC/ABS 60/40 blends surface (5): no etching (a), etched for 5 min (b), and etched for 15 min (c), in sulfochromic solution (350 g/L chromic acid and 400 g/L sulfuric acid), and at 70 8C.
Source publication
As replacement for acrylonitrile-butadiene-styrene (ABS), which is commonly used in the manufacture of chrome parts, polyvinyl chloride (PVC) and PVC/ABS blend parts were produced by injection process, etched in sulfochromic solution in different concentrations, immersion time, and temperature, and they were subsequently chrome-plated by convention...
Contexts in source publication
Context 1
... acid (300 g/L) and Sulfuric acid (400 g/L) Surface Morphology of ABS, PVC, and PVC/ABS Blends Figure 2 shows the SEM images of ABS, PVC, and PVC/ABS blend surfaces before and after etching in sulfochromic solution (350 g/L chromic acid and 400 g/L sulfuric acid), for an immer- sion time of 5 and 15 min, and at 70 8C. ABS samples without chemical conditioning are fairly uniform structures, with the lines from imperfections in the injection mold being visible. ...
Context 2
... and PVC/ABS blends with higher ABS (PVC/ABS20/80) content were more susceptible to attack by sulfochromic solution than PVC samples when treated for 5 min. Changes in surface morphology, such as irregularly shaped pores, cavities and micro holes can be observed in Figure 2(3b). However, only the ABS sample was approved in the adhesion test for this etching time. ...
Context 3
... sulfochromic solution causes removal of ABS surface components, mainly the butadiene by oxidation, while the PVC is more chemically resistant. Longer treatment time of 15 min promoted more significant changes on the surface samples, as observed in Figure 2(3c), and PVC/ ABS20/80 blend was approved in the metal adhesion test. PVC and PVC/ABS blends with higher contents of PVC, conditioned for 15 min, caused different changes on the surface of these samples such as a less rough appearance, presence of pores, and more defined undulations, as observed in Figure 2(4c and 5c). ...
Context 4
... treatment time of 15 min promoted more significant changes on the surface samples, as observed in Figure 2(3c), and PVC/ ABS20/80 blend was approved in the metal adhesion test. PVC and PVC/ABS blends with higher contents of PVC, conditioned for 15 min, caused different changes on the surface of these samples such as a less rough appearance, presence of pores, and more defined undulations, as observed in Figure 2(4c and 5c). In this case, although the sulfochromic solution presented a less aggressive attack on the surface, it was, nevertheless, sufficient to cause the metal adhesion in the PVC and PVC/ABS40/60 blend. ...
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Citations
... There is some dust as a result of chamber cleaning, but it creates no disposal issues. [39]. ...
Chromium plating process is the most effective way of protecting the base material against hostile environment or improving surface properties of base material. There are several problems with traditional chrome plating. Traditional process uses toxic acid baths and may cause various health conditions. The baths employed contain chromic acid in which the chromium is in the hexavalent state. Hexavalent chromium has been proved to have toxic, mutagenic and cancerogenic effects for human health. As a result, In Europe, the implementation of the reach initiative will increase fees on companies still using Cr (VI) in 2017 and will require action plans to phase out Cr (VI) in the future. This has left the plating industry in a very delicate position with dark future prospects unless new solutions that are both effective and environmentally friendly are discovered. Superchrome Physical Vapor Deposition coating ahead of looming industry regulatory actions that will drive towards the removal of hazardous hexavalent chromium compounds. These new sputtered chromium coatings do not require a protective paint top coat to pass exterior automotive trim specifications. Visually the chromium coatings match those of electroplated decorative chromium in color and appearance.
... Tape test is indeed a popular adhesion test in industry and academia as it is currently the simplest and low-cost technique available for measuring the adhesion characteristics of metal-polymer interface [25,42,44,45]. Nonetheless, as stated in ASTM D3359-17 [38], the tape test has several inherent limitations. ...
... At the same time PVC interacts more with SAN than with rubber. It follows that the interaction between SAN and PVC is decisive in the creation of PVC/ABS blends [30][31][32][33]. ...
The work is devoted to the development of formulations intended for the production of profiled molding products of various functional purposes. Polymer mixtures based on polyvinyl chloride were widely used for production of profiles. Different concentrations (from 7 to 40 parts per hundred parts of polyvinyl chloride resin) of acrylonitrile butadiene styrene copolymer were used as an additive polymer. Experimental samples were made in the form of flat profiles by extrusion. The technological and structural parameters of the polymer mixture based on polyvinyl chloride were considered. It was found that the presence of acrylonitrile butadiene styrene in the entire concentration range leads to easier recyclability, which is confirmed by high melt flowability. In the region of low concentrations of elastomer (7 and 10 parts per hundred parts of polyvinyl chloride resin) a synergistic effect on expanding is observed, and increase of acrylonitrile butadiene styrene concentration up to 40 parts per hundred parts of polyvinyl chloride resin results in higher elasticity, thermal stability and decrease of microhardness. To explain the results obtained, the supramolecular structure of the composites was evaluated by scanning electron microscopy.KeywordsPVCABSModificationPolymer blendsMoulded parts
... При этом ПВХ больше взаимодействует с САН, чем с бутадиеном. Из этого следует, что взаимодействие между САН и ПВХ является определяющей при создании смесей ПВХ/АБС [14][15][16][17]. ...
The work is devoted to the filling of PVC (polyvinyl chloride) compositions modified with ABS (acrylonitrile-butadiene styrene) in a wide concentration range, intended for the production of profiles and moldings of various functional purposes, with short-fiber basalt fiber. Powdered samples were made by extrusion (in the form of flat profiles) and by thermoplasticizing on rolls (in the form of films). Introduction of 10-40 phr ABS in PVC formulation makes it easier to recycle the composition. Similar situation is observed when these compositions are filled with basalt fiber, which leads to insignificant decrease of MFR (melt flow index) and thermal stability, which in general does not reflect negatively on melt flow conditions, at the same time extrudate swelling index decreases by 10-15%, which indicates possibility to provide products with more precise geometric dimensions. The change in the supramolecular structure was evaluated by thermomechanical tests and by energy dispersive analysis using electron microscopy data. Thermomechanical analysis showed that the presence of large doses of ABS has a positive effect on the technological properties, leading to an earlier development of highly elastic deformations and a decrease in the yield point of the compositions. Basalt fiber contributes to an insignificant decrease in the value of high elastic deformations and an increase in the density index of meshing knots. Energy dispersion analysis has shown that introduction of basalt fiber leads to formation of homogeneous structure of PVC at lower concentrations of ABS in the composition, influencing on increase of melt flowability and thermal stability. Improved technological properties of PVC compositions filled with short-fiber basalt fiber, modified with different concentrations of ABS, allow to recommend them for production of a wide range of profile and molded products.
... In addition, PVC/ABS blends are of interest due to the compatibility of the styrene-acrylonitrile phase in the block copolymer of ABS and PVC depending on the phase structure of the blend. Therefore, PVC is often used to improve process properties [25][26][27][28]. ...
The work is devoted to the development of rigid polyvinyl chloride (PVC) compositions for obtaining materials for construction with new properties. Acrylonitrile-butadiene styrene copolymer (ABS) was added to the mixed composition in different concentrations (from 10 to 40 parts per 100 parts of PVC resin). The performance and structural parameters of the extruded flat profiles were considered. Increasing the concentration of ABS leads to changes in the technological and operational properties of the composites. This work shows the influence of the features of the supramolecular structure of composites on the properties when the concentration of copolymer is increased: weight reduction of samples, increase of high elastic deformation, hardness and bending strength, as well as increase of heat resistance and decrease of the flowing temperature.
... These products may undergo corrosive oxidation when in contact with body fluids, such as sweat and saliva, and thus part of the chromium can be released into the aqueous environment (body fluids) in the form of ions. In laboratory and industrial processes, sulfuric acid acidified potassium dichromate solution (also known as sulfochromic mixture) is usually used for pretreatment of polymer electroless plating, SiO 2 coating and glassware washing (Barhoumi et al., 2005;Peris Vicente et al., 2005;Kurek et al., 2017). The wastewater from these processes, when improperly treated or discharged, may cause serious environmental pollution. ...
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The peel‐off strength of the electroplated specimens exhibits corresponding increase, particularly pronounced in ABS‐rich blends. However, it is observed that the interface displays incomplete contact between the metal and polymer. We suggest a new parameter, the Sdr ratio (Sdr,polymer/Sdr,plating), which provides the prediction of the adhesion strength of the physically interlocked metal‐polymer interface. The change in Sdr ratio effectively reflects the change of peel‐off strength, which is more efficient for phases with increasing ABS content. By examining the relationship between surface morphology and adhesion strength, our research provides the insights into optimizing the adhesion properties of electroplated metal‐polymer interfaces for PC/ABS blend. image
Electroplating of metals on polymer materials is one of the best decorative processes for achieving low cost and light weight. However, low interfacial adhesion often limits practical utilization due to the potential peel-off behavior of metal layers. The interface between the metal layers and acrylonitrile-butadiene-styrene (ABS) substrate and its peeling mechanism are investigated as a function of etching time. Sa, the arithmetic average roughness of the unit area, and Sdr, the interfacial area ratio, are adopted instead of linear roughness, Ra, to quantify the surface profile. As the etching time increases, both Sa and Sdr for the etched ABS and corresponding metal side increase. The failure mode changes from adhesive to cohesive as the etching time increases, and the peel-off strength of the electroplated ABS exhibits a dependence on the tensile strength of the substrate. The peel-off strength of the electroplated ABS specimens increases to 8.46 N/cm after 30 min of etching time, but the interface degrades, forming inner voids. The Sdr ratio (Sdr, polymer / Sdr, plating) is proposed as a surface parameter to predict the peel-off strength of electroplated ABS and represents a new attempt to quantitatively correlate the interfacial morphology with the adhesion strength.
In this study, we applied a clean, effective and low-cost modification method using light-activated chlorine dioxide radical (ClO2•) to oxidize the surface of ABS resin. An increase in the amount of surface polar groups resulting from the incorporation of oxygen-containing groups into polybutadiene (PB) and improvement in the surface hydrophilicity of ABS resin were observed after oxidation. The oxidized ABS resin exhibited good adhesion to the metal layer after electroless metal plating. This method could be applied as an effective approach for electroless plating. The investigation of the effects of oxidation time and temperature on surface modification and electroless plating shows that the mild conditions of oxidation for 10 min at room temperature is optimal. In addition, as light irradiation was not required for the modification of plastics via this process, this modification method was successfully used for ABS resin with complex shapes, which broadened its practical applicability.
One of the barriers to the recycling of chrome plated acrylonitrile–butadiene–styrene (ABS) is the degradation caused by the solution containing nitric acid used in the pickling of the metal layer. In this study, defective chrome plated ABS parts were pickled in a solution composed of lactic and sulfuric acids and hydrogen peroxide, and recycled by injection molding with different proportions of virgin ABS. The influence of pickled ABS on the chemical composition, thermal and mechanical properties of the samples was evaluated. The samples were chrome plated and characterized by visual inspection and adhesion tests. A slight yellowing of the virgin ABS/pickled ABS samples was observed due to the degradation of butadiene component. The thermal and mechanical properties were similar to those of virgin ABS. After the new chrome plating, all samples were approved in the adhesion tests, demonstrating that pickled ABS can be recycled by injection molding and chrome plating.
