Composite manhole covers prepared with recycled printed circuit boards as a reinforcing filler

Abstract

Waste circuit boards particles (CBPs) were utilized as a reinforcing filler to prepare bulk molding composites (BMCs) for the manufacture of composite manhole covers (CMCs) without reinforcing ribs. The effects of CBPs and conventional CaCO 3 on the mechanical properties of the BMCs were comparatively determined. Compared to CaCO 3 , CBPs showed a higher compatibility with unsaturated polyester resin (UPR) while effectively improving the fluidity of premix and the mechanical properties of the BMC. To enhance the interfacial adhesion between the glass fiber (GF) and UPR, three kinds of amine, epoxy, and vinyl modified silanes (namely KH-550, KH-560, and KH-570, respectively) were used. The surface tension (c) of the GF significantly decreased upon modification with the coupling agents. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) characterizations revealed a strong adhesion between the GF and UPR, thereby enhancing the mechanical properties of the composite material. The BMC material showed optimal flexural strengths upon addition of KH-560 and KH-570 coupling agents at 4 wt%. With the aim of evaluating its mechanical performance, a constant loading test combined with an ANSYS finite element analysis was performed over the prepared CMC. According to the constant loading test, the CMC material showed a stress loading of 7.8 tons, which was close to the value obtained by ANSYS simulation. POLYM. COMPOS., 00:000-000, 2017. V C 2017 Society of Plastics Engineers

Polypropylene Composites Reinforced by Nonmetallic from Waste Printed Circuit Boards Using Spout-Fluid Bed Coating with PP Particles Enhance Fluidization

“…New reticular membranes or organic long chains on the surface of the modified particles were formed from the associated reaction of hydrolyzed KH-550. A reticular membrane led to an organic surface of the N-WPCBs and decreased the polarity of the N-WPCBs, which enhanced the compatibility of the PP matrix and N-WPCB particles [ 10 ]. Interfacial bonding between the PP matrix and N-WPCB particles was enhanced through the organic long chains.…”

“…Luo et al reported that N-WPCBs were used as reinforcing fillers in rubbers. The tensile strength of rubber composites sharply increases to 18 MPa with the use of grafted polymers, which also significantly improves the thermal oxidation resistance [ 10 ]. Grigorescu et al used N-WPCBs as fillers to improve the fire resistance of thermoplastic composites based on recycled polypropylene and diene block copolymers, and the impact strength was observed [ 11 ].…”

Damage Evaluation of the Paving around Manholes under Vehicle Dynamic Load

“…At present, research on manholes and the paving around manholes mostly focuses on manhole settlement mechanisms [6], new manhole structures [7][8][9], damage analysis of the paving around manholes [10], and treatment technology for pavement damage [11,12], and the control of damage to paving around manholes has improved to some extent.…”

Reutilization of waste printed circuit boards nonmetallic powders in elastomer composites: Significant improvements of curing and mechanical properties

“…Printed circuit boards as fundamental building blocks for electronic device have been increasingly applied in all sorts of areas of electronic industry . With the continuous renewal of electronic products, the resulting waste printed circuit boards (WPCB) including off‐cuts during manufacturing and end‐of‐life components are extensively stacking up, the proper deposal of WPCB therefore has been the issue of common concern from scientific and industrial researchers .…”