Rigid polyurethane foams reinforced with ultrafine powder from automotive shredder residue

Abstract

With the booming of the abandoned cars, automobile shredding residual (ASR) increase sharply in recent years. ASRs contain complex components that are difficult to separate and recycle, causing serious environmental impacts. Herein, we report a new strategy for ASR recycling to prepare high value‐added rigid polyurethane foams (RPUFs) with excellent mechanical and thermal properties. Ultrafine ASR powder with homogeneous domain size and activated functional groups, added to the precursor of RPUFs as reinforcing fillers, was fabricated through solid‐state shear milling (S3M) technology. As a nucleating agent, ASR particles can participate in the foaming procedure of RPUFs, which decreased the cell size to ~0.2 mm. Owing to the strong interaction between the ASR and polyurethane matrix, the thermal degradation temperature increased to 246.7°C, 42.4°C higher than the neat one. Inspiringly, the ASR particles can act as reinforcing elements in the cell walls, which can not only increase the compressive strength and modulus to 1.79 and 0.1 MPa respectively, 81% and 71% higher than the neat sample, but also enhance the long‐term fatigue resistance of the foam. This strategy achieves the recycling and utilization of ASR, and expands the application scope of RPUFs as well.

A Review on Mechanochemistry: Approaching Advanced Energy Materials with Greener Force

“…The effect of ultrafine pulverization and mixing enables S 3 M processes to recycle waste polymer materials that are difficult to separate, blend, and process at room temperature. [79,80] On the one hand, for solid wastes with complicated constituents that are difficult to separate, S 3 M can weaken the effect of compatibility and matched viscosities by controlling the domain size of multiple phases via the particle size and distribution of the resulting composite powder, thus controlling the performance of the products obtained from recycled automobile shredder residual, [81] printed circuit board waste, [82] and aluminum plastic packaging [83] (Figure 3d). On the other hand, the powerful squeezing and shearing action that occurs during S 3 M processing can destroy the cross-linked bonds in cross-linked waste such as cross-linked polyethylene, [81] rubber, [84] and solid leather waste, [68,85] endowing these materials with better processability.…”

“…[79,80] On the one hand, for solid wastes with complicated constituents that are difficult to separate, S 3 M can weaken the effect of compatibility and matched viscosities by controlling the domain size of multiple phases via the particle size and distribution of the resulting composite powder, thus controlling the performance of the products obtained from recycled automobile shredder residual, [81] printed circuit board waste, [82] and aluminum plastic packaging [83] (Figure 3d). On the other hand, the powerful squeezing and shearing action that occurs during S 3 M processing can destroy the cross-linked bonds in cross-linked waste such as cross-linked polyethylene, [81] rubber, [84] and solid leather waste, [68,85] endowing these materials with better processability. It is worth mentioning that because S 3 M treatment results in the retention of a small amount of microcross-linked structures, the mechanical properties of recycled products can be enhanced.…”

Practicality of physical recycling method for waste polymer composites exampled via high density polyethylene/automobile shredder residue composites

“…1,2 Automobile shredder residue (ASR) is the remaining part after dismantling, crushing and sorting the abandoned cars, featuring extremely complex composition, such as polymers, inorganics (the glass, sand stone) as well as metals. [3][4][5][6][7] Although polymeric materials account for its major component, the mismatch of viscosity and melting point makes ASR impossible for conventional melt processing. 8 Therefore, landfill and incineration were mainly used for disposal.…”

Flame‐retarded rigid polyurethane foam conferred by an amino trimethylphosphonate iron and expandable graphite compound flame retardant

“…Song et al prepared high value‐added RPUFs with excellent mechanical and thermal properties from automobile shredding residual. [ 12 ] Gong et al synthesized a phosphaphenanthrene groups containing soybean oil based polyol (DSBP) and soybean oil based polyol (HSBP). [ 13 ] Then, the corresponding RPUFs were prepared by mixing DSBP with HSBP.…”