scholarly journals Composites of Styrene-Butadiene Block Copolymer Reinforced with Waste Printed Circuit Boards (WPCB)

Proceedings ◽  
2019 ◽  
Vol 29 (1) ◽  
pp. 19
Author(s):  
Paul Ghioca ◽  
Madalina Elena David ◽  
Mircea Ioan Filipescu ◽  
Ramona Marina Grigorescu ◽  
Lorena Iancu ◽  
...  

The organic part of the waste printed circuit board (WPCB) contains mainly epoxy resin, fiberglass and brominated flame retardants, a composition that makes it quite difficult to reuse [1,2]. [...]

2010 ◽  
Vol 113-116 ◽  
pp. 730-734 ◽  
Author(s):  
Chen Long Duan ◽  
Yue Min Zhao ◽  
Jing Feng He ◽  
Nian Xin Zhou

The reutilization of waste Printed Circuit Boards (PCB) is a focused topic in the field of environment protection and resource recycling, and the crushing is the crucial process for recycling waste PCB. A hamper impacting crusher was used to achieve metals crushing liberation from non-metals, the liberation mechanism of PCB can be explained by dispersion liberation accompanied disengaging liberation. The Rosin-Rammler distribution model of crushed PCB particle was put forward. The evaluation indexes show that Rosin-Rammler function can accurately describe size distribution of PCB particles because the convergence property R2 is 0.99694 and fitting error E is 4.80658. The selective crushing is appearance with metals concentrated in coarser fraction and non-metals in finer size during comminution processing. The impact crushing is an effective method to metals liberation of PCB particles.


2015 ◽  
Vol 787 ◽  
pp. 18-21 ◽  
Author(s):  
A.G. Ganesh Kumar ◽  
G. Ranganath ◽  
S.N. Mani Varmaa ◽  
S. Shylin H. Jose ◽  
M. Sakthivel

Recycling of Printed Circuit Boards (PCB) has been carried out by powdering it into granular size of less than 10 microns. The properties of PCB reveal that it possesses density of 1.3 g/cm3 and Tensile Strength of 310 MPa which is comparatively high when compared to the Polycarbonate material which is normally used in the fabrication of Riot shield. The PCB material was subjected to SEM and EDAX analysis for determining their structure, porosity and material composition. Riot shield fabricated from PCB reduces the environmental effects of E-waste PCBs by the recycling technique, improves the material strength and reduces the weight and cost to a larger extent.


2021 ◽  
Author(s):  
Weifang Chen ◽  
Yongkai Shu ◽  
Yonglun Li ◽  
Yanjun Chen ◽  
Jianbo Wei

Abstract Waste printed circuit board was co-pyrolyzed with iron oxides and iron salts. Solid, liquid and gaseous products were collected and characterized. Co-pyrolysis with FeCl2, FeCl3 or FeSO4 was able to increase the yield of liquid product which was rich in phenol and its homologues. Also, the addition of co-pyrolysis reagents reduced the release of brominated organics to liquid as Br was either fixed as FeBr3 in solids or released as HBr. In particular, FeCl2 showed the best ability to reduce the release of Br-containing organics to liquid compared with FeCl3 and FeSO4. Solid residuals were rich in iron oxides, glass fibers and charred organics with surface areas of 20.6-26.5 m2/g. CO2 together with a small amount of CH4 and H2 were detected in the gaseous products. Overall, co-pyrolysis could improve the quantity and quality of liquid oil which could be reused as chemical or energy sources. Pyrolysis of waste printed circuit board was promising as a method for recycling.


2015 ◽  
Vol 4 (2) ◽  
pp. 70-75
Author(s):  
Şule Atasever ◽  
Pınar A. Bozkurt ◽  
Muammer Canel

Electrical and electronic apparatus and instruments which are obsolete value in use or completion of the life can be defined as e-waste. E-waste is one of the fastest growing types of hazardous waste. Printed circuit boards a major component of this waste. In this study, printed circuit board particles of mobile phone (MPCB) were used as electronic waste. MPCB waste was obtained from a local electronic waste factory. The elemental analysis and ICP-MS analysis were performed on these electronic wastes and thereafter pyrolysis runs were carried out between 500 and 900°C in a horizontal furnace. The liquid yields were determined and compared at different temperatures.


2020 ◽  
Author(s):  
V.M. Alexeenko ◽  
L.G. Ananieva ◽  
A.A. Zherlitsyn ◽  
S.S. Kondratiev ◽  
M.V. Korovkin ◽  
...  

The results of the electric discharge crushing of PCB (printed circuit boards) to millimeter-sized fractions suitable for separation of the metal from the dielectric are presented. The crushing was performed on a high-voltage repetitively pulsed generator with varying the number of pulses. It was determined the dependences of the fractional composition of crushing products on the number of pulses in the cycle. Crushing products were studied for definition separation of metal from the dielectric with optical microscope. The results of the work confirm the possibility of electric discharge crushing various types of PCB, including fiberglass PCB with four layers. Keywords: high voltage fragmentation, waste printed circuit board, recycling


2019 ◽  
Vol 37 (6) ◽  
pp. 569-577 ◽  
Author(s):  
Rajesha K Das ◽  
Omdeo K Gohatre ◽  
Manoranjan Biswal ◽  
Smita Mohanty ◽  
SK Nayak

Extreme complexity in the range of metallic and non-metallic parts present in waste printed circuit boards leads to incineration for collecting valuable metals. The non-metallic parts of the printed circuit board can be used effectively without affecting the environment. In this study, the non-metallic parts of the printed circuit board, which is made up by cross-linked resin and fibre, was used as a filler in recycled plasticised polyvinyl chloride collected from waste wires and cables. The properties of the plasticised polyvinyl chloride matrix and plasticised polyvinyl chloride–non-metallic parts of printed circuit board composite were compared with each other by means of mechanical properties and thermal properties. Both mechanical and thermal properties results indicated that incorporation of non-metallic parts of printed circuit board significantly improved the hardness, stiffness, abrasion resistance and thermal stability of plasticised polyvinyl chloride–non-metallic parts of printed circuit board composite; however, the tensile strength of the composite material is not improved because of poor adhesion between the plasticised polyvinyl chloride matrix and non-metallic parts of printed circuit board filler. The poor chemical interaction is also observed from Fourier transform infrared spectroscopy results. This plasticised polyvinyl chloride–non-metallic parts of printed circuit board composite can reduce the leaching of a hazardous element from the printed circuit board with effective utilisation of plastics fraction from waste wires and cables.


Author(s):  
P. Singh ◽  
G.T. Galyon ◽  
J. Obrzut ◽  
W.A. Alpaugh

Abstract A time delayed dielectric breakdown in printed circuit boards, operating at temperatures below the epoxy resin insulation thermo-electrical limits, is reported. The safe temperature-voltage operating regime was estimated and related to the glass-rubber transition (To) of printed circuit board dielectric. The TG was measured using DSC and compared with that determined from electrical conductivity of the laminate in the glassy and rubbery state. A failure model was developed and fitted to the experimental data matching a localized thermal degradation of the dielectric and time dependency. The model is based on localized heating of an insulation resistance defect that under certain voltage bias can exceed the TG, thus, initiating thermal degradation of the resin. The model agrees well with the experimental data and indicates that the failure rate and truncation time beyond which the probability of failure becomes insignificant, decreases with increasing glass-rubber transition temperature.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
P. Sivakumar ◽  
D. Prabhakaran ◽  
M. Thirumarimurugan

The aim of the study was to recover copper and lead metal from waste printed circuit boards (PCBs). The electrowinning method is found to be an effective recycling process to recover copper and lead metal from printed circuit board wastes. In order to simplify the process with affordable equipment, a simple ammonical leaching operation method was adopted. The selected PCBs were incinerated into fine ash powder at 500°C for 1 hour in the pyrolysis reactor. Then, the fine ash powder was subjected to acid-leaching process to recover the metals with varying conditions like acid-base concentration, electrode combination, and leaching time. The relative electrolysis solution of 0.1 M lead nitrate for lead and 0.1 M copper sulphate for copper was used to extract metals from PCBs at room temperature. The amount of lead and copper extracted from the process was determined by an atomic absorption spectrophotometer, and results found were 73.29% and 82.17%, respectively. Further, the optimum conditions for the recovery of metals were determined by using RSM software. The results showed that the percentage of lead and copper recovery were 78.25% and 89.1% should be 4 hrs 10 A/dm2.


2018 ◽  
Vol 10 (2) ◽  
pp. 179-186 ◽  
Author(s):  
Alexander Fricke ◽  
Mounir Achir ◽  
Philippe Le Bars ◽  
Thomas Kürner

AbstractBased on vector network analyzer Measurements, a model for the specular reflection behavior of printed circuit boards in the Terahertz range has been derived. It has been calibrated to suit the behavior of the measurements using a simulated annealing algorithm. The model has been tailored for integration to ray-tracing-based propagation modeling.


Cryptography ◽  
2020 ◽  
Vol 4 (2) ◽  
pp. 11
Author(s):  
Mitchell Martin ◽  
Jim Plusquellic

Physical Unclonable Functions (PUFs) are primitives that are designed to leverage naturally occurring variations to produce a random bitstring. Current PUF designs are typically implemented in silicon or utilize variations found in commercial off-the-shelf (COTS) parts. Because of this, existing designs are insufficient for the authentication of Printed Circuit Boards (PCBs). In this paper, we propose a novel PUF design that leverages board variations in a manufactured PCB to generate unique and stable IDs for each PCB. In particular, a single copper trace is used as a source of randomness for bitstring generation. The trace connects three notch filter structures in series, each of which is designed to reject specific but separate frequencies. The bitstrings generated using data measured from a set of PCBs are analyzed using statistical tests to illustrate that high levels of uniqueness and randomness are achievable.


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