Grinding and Separation of The Cellular Phone Housing

2005 ◽  
Vol 895 ◽  
Author(s):  
Woo-Hyuk Jung ◽  
Nathan Tortorella ◽  
Charles L. Beatty ◽  
Stephen P. McCarthy

AbstractThe front covers of Motorola cellular phone housings, which were composed of 62.2 wt% of polycarbonate (PC) /acrylonitrile-butadiene-styrene (ABS), were ground and separated from the undesired materials using sink-float methods. The sink-float methods in water and salt were used to remove the floating materials such as the adhesive strips and the foams, and to separate the metal parts where the recovery ratios were 92.8 and 40.5 %, respectively. The separation of residual wires and button rubbers, which could not be done by the sink-float process in water, was preformed using V-Stat Triboelectric Separator (Outokumpu Technology) of a roll separator that also provided the effective methods to separate the ground metals that had existed in the printed circuit boards where the recovery weight ratio of metal parts was 19 wt%. The separated PC/ABS’s could be compounded with the ground circuit boards or the thermoplastic elastomer called Engage®, or the reactive species of glycidyl methacrylate (GMA).

2005 ◽  
Vol 895 ◽  
Author(s):  
Woo-Hyuk Jung ◽  
Nathan Tortorella ◽  
Charles L. Beatty ◽  
Stephen P. McCarthy

AbstractThe front cover of Motorola cellular phone housings were ground to the same size as original particles prior to use by a knife mill. The mixtures contained 15.2 wt% metals, 1.9 wt% foams, 1.4 wt% rubbers and 81.4 wt% thermoplastics where the major component was a polycarbonate (PC)/acrylonitrile-butadiene-styrene (ABS) blend. The separation of the thermoplastic scraps was performed using the sink-float process in water and salt solution. The impact modification of all housing containing six thermoplastic parts was carried out by the addition of a polyolefin elastomer called as the functionalized polyethylene (PE). Unprinted glass fiber reinforced epoxy circuit boards were size reduced and pulverized using the knife mill and hammer mill. The ground epoxy circuit boards were then classified with a set of testing sieves using Gyro sifter, and their mean diameters were calculated by means of particle size distribution analysis. Izod impact strengths at two temperatures, tensile tests, scanning electron microscopy (SEM) on the fracture surfaces, and dynamic mechanical spectroscopy were performed to characterize the alloys and mixtures compounded by a batch mixer and a twin screw extruder.


2008 ◽  
Vol 128 (11) ◽  
pp. 657-662 ◽  
Author(s):  
Tsuyoshi Maeno ◽  
Yukihiko Sakurai ◽  
Takanori Unou ◽  
Kouji Ichikawa ◽  
Osamu Fujiwara

2018 ◽  
Vol 23 (2) ◽  
pp. 141-148
Author(s):  
S.Sh. Rekhviashvili ◽  
◽  
M.O. Mamchuev ◽  
V.V. Narozhnov ◽  
M.M. Oshkhunov ◽  
...  

2013 ◽  
Vol 61 (3) ◽  
pp. 731-735
Author(s):  
A.W. Stadler ◽  
Z. Zawiślak ◽  
W. Stęplewski ◽  
A. Dziedzic

Abstract. Noise studies of planar thin-film Ni-P resistors made in/on Printed Circuit Boards, both covered with two different types of cladding or uncladded have been described. The resistors have been made of the resistive-conductive-material (Ohmega-Ply©) of 100 Ώ/sq. Noise of the selected pairs of samples has been measured in the DC resistance bridge with a transformer as the first stage in a signal path. 1/f noise caused by resistance fluctuations has been found to be the main noise component. Parameters describing noise properties of the resistors have been calculated and then compared with the parameters of other previously studied thin- and thick-film resistive materials.


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