Nonreactive Processing of Recycled Polycarbonate/Acrylonitrile–Butadiene–Styrene

Abstract

Front covers of Motorola cellular phones, ground by a knife mill, contain 15.2 wt% metals, 1.9 wt% foams, 1.4 wt% rubbers, and 81.4 wt% thermoplastics with polycarbonate=acrylonitrile-butadiene-styrene blends. Separation of the thermoplastic scraps was performed using sink-float processes in water and salt solutions and electrostatic processes such as free-fall methods and roll separations. Impact modification of all housing containing six thermoplastic parts was carried out by the addition of a polyolefin elastomer. Unprinted and printed glass fiber-reinforced epoxy circuit boards were finely pulverized using a knife mill and a hammer mill. Ground printed circuit boards, separated by a roll separator, were compounded with desired thermoplastic mixtures. Izod impact strengths at various temperatures, tensile tests, scanning electron microscopy on fracture surfaces, and dynamic mechanical spectroscopy were performed to characterize the alloys and mixtures compounded by a batch mixer and twin screw extruder. Impact strength of the pure housing materials was almost twice higher than that of all housing materials compounded by the batch mixer. The polymer alloys compounded by the twin screw extruder showed lower impact strengths but higher tensile properties than those by the batch mixer because of the break-up of the interfacial instability.

Polymer Recovery from Auto Shredder Residue by Projectile Separation Method

“…If polymers have very close specific gravities, it is possible to add a swelling agent to increase the volume of either one of the targeted polymers, thus effectively reducing its density [24]. A major drawback of this method is that it is a wet separation process and thus requires drying of the recovered polymers, often overnight in a drying oven at 45 °C, this process cannot be hastened by increasing the temperature of the oven as the polymers could soften should the temperature be set too high [25]. Another drawback is the fact that it takes a fair amount of time for the polymeric particles in the mixture to settle and it also requires one separation step for each polymer, making this a multi-stage system which is a very slow process.…”

On 3D printing of electro-active PVDF-Graphene and Mn-doped ZnO nanoparticle-based composite as a self-healing repair solution for heritage structures

“…[6][7][8][9][10][11] Some studies reported on biomedical applications and thermal conductivity of PVDF highlighted that such special polymers with phase changing and chemical stability capabilities can be investigated intensely for many other aspects. 12,13 Based upon reported literature it has been observed that large-scale applications of 3D printing in construction are being explored by the researchers to reduce the cost and time of construction, its repair, and maintenance. [12][13][14][15] Many studies have been reported on the use of solid plastic waste, mortarpolymer mixture, and sulfoaluminate high activity material for constructional 3D printing, and investigations were performed on self-healing hydrogels-based composites.…”

“…12,13 Based upon reported literature it has been observed that large-scale applications of 3D printing in construction are being explored by the researchers to reduce the cost and time of construction, its repair, and maintenance. [12][13][14][15] Many studies have been reported on the use of solid plastic waste, mortarpolymer mixture, and sulfoaluminate high activity material for constructional 3D printing, and investigations were performed on self-healing hydrogels-based composites. [14][15][16][17][18] Further, some work has been reported on smart polymer materials, geo-polymer, PVDF, Gr, smart composites for civil constructional applications of 3D printing for maintenance and repair of cultural heritage structures.…”