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Polyurethane (PU) foams were recovered from European and U.S. shredder residues, which typically come from automobiles and other sources of durable goods, such as appliances, furniture, construction, etc. PU foams were characterized and glycolyzed. Glycolysis products were successfully treated for the removal of select substances of concern, heavy metals, and bromine-containing compounds and propoxylated into polyols for polyurethanes with 171 and 355 average equivalent weights. Properties of the glycolysis product and corresponding propoxylated polyols were evaluated, including their molecular weight distribution via gel permeation chromatography (GPC). The polydispersity index decreased from 5.8 to 2.1 by reaction of glycolysis product with 50 wt% of propylene oxide based on a total amount of the initiator. The recycled polyol of an average equivalent weight of 171 was evaluated in rigid polyurethane and urethane-modified isocyanurate foam formulations.

Using automated separation, a mixed plastic stream can be recovered from shredder residue (SR). However, the mixed plastics may be contaminated with dirt, oils, heavy metals, and substances of concern (SOCs). To remove these contaminates from the mixed plastics, the plastics must be washed and cleaned. According to the U.S. Environmental Protection Agency (U.S. EPA), the recovered mixed plastic needs to contain less than 2 ppm of Polychlorinated Biphenyls to be introduced into commerce, thereby setting the performance criteria for the washing systems. This paper describes the performance and safety criteria for the washing systems, the selected washing processes, and the factors contributing to the economy of mixed plastics washing.

Tons of shredder residue (SR), a complex mixture of plastics, foams, rubber, metals, and glass, are generated each year as a by-product from the recycling of obsolete vehicles. The Vehicle Recycling Partnership (VRP), along with our CRADA partners, is investigating ways to enable the optimum recovery and recycling of these materials. This study investigates the feasibility of recycling (PU) foam using a new chemical process by glycolysing [1, 2] two types of polyurethane (PU) foams, “dirty” and “clean”, which were recovered from SR via an industrial scale process specifically designed to separate PU foams from SR [3, 4]. In stage one of this process, the polyurethane foam is subjected to glycolysis, followed by filtration of the liquid glycolyzed product. In stage two, the glycolyzed products are used as initiators in reaction with propylene oxide to prepare novel polyurethane polyols.

Shredder residue is a complex mix of many different materials that includes plastics, rubber, polyurethane (PU) foams, glass, metals and other materials such as rocks and dirt. The metal recyclers create this shredder residue mix as part of a recycling process to recover metals. The actual input stream for metal recycling is end-of-life automobiles, white goods and a variety of other metal-intensive parts including industrial scrap waste. This shredder residue is currently landfilled, and the European Union has implemented laws to reduce the amount of shredder residue from automobiles that can go into landfills. The Vehicle Recycling Partnership (VRP) is working with different collaborators to evaluate different technologies, including automated plastic recovery, as a means to reduce the amount of plastics that go to landfill in shredder residue.

The Vehicle Recycling Partnership (VRP) initiated feasibility studies to evaluate the use of automated separation processes to recover plastics and polyurethane (PU) foams from shredder residue. One of the prevailing issues impeding the commercial success of these processes is contamination of the shredder materials. The contaminants include dirt, oils, glass, metal fines, polychlorinated biphenyls (PCBs) and heavy metals. The presence of PCBs and heavy metals was determined in a number of mixed plastics and PU foam samples separated using an automated separation process. An aqueous cleaning approach was investigated using various commercial surfactants to determine their effectiveness for removing oils, PCBs, and heavy metals. Mass balances of processed and cleaned materials were calculated to determine the cleaning efficiencies of the various surfactants.

About 11 million vehicles are scrapped each year in the United States. Most of these vehicles are recycled by automotive dismantlers and shredders. Presently, about 95% of the ferrous and non-ferrous metals present in vehicles (75% of the total vehicle weight) are recovered. The remainder of the scrapped vehicles (non-metal portion known as automotive shredder residue-ASR) is landfilled, generating up to 3 million tons of waste per year. In order to increase the efficiency of recovery of both ferrous and non-ferrous metals from the shredded vehicles, numerous developments have been made by the shredders in separation technology recently. This paper is an update of our previous paper and contains in-depth characterization of the various ASR streams.

A number of prototype automotive interior trim products were developed from polyurethane-cored headliner scrap by utilization of isocyanate-based binders: 1) rear-seat-to-back-window trim panels (Deville and Eldorado Chimsl covers), 2) package trays (Neon PL-tray, Buick/Oldsmobile G-trays), and 3) sun-shades (Accord/Acura sun-shades). The technology for the manufacture of these products is outlined in this paper as well as their mechanical, acoustical, and other properties relevant to the automotive interior trim applications.

Most studies on the properties and recycling of automotive shredder residue (ASR) have been carried out without fully understanding the composition of the input scrap. Equally important is understanding the type of shredding process, and types of processes utilized for separation of ferrous and non-ferrous metals from the shredded material. The Vehicle Recycling Partnership (VRP) has been conducting a project:“Study of Plastic Material Recovery From Automotive Shredder Residue” [1]. One of the objectives of this VRP project is to determine the relationship between the shredder input and ASR properties. A 1995 Dodge Stratus was dismantled in detail to obtain information necessary for the project, such as material usage in the vehicle [2]. Then, under tightly controlled conditions, 14 late model Chrysler Cirrus and Dodge Stratus automobiles were shredded and processed.

A method for recycling of mixed color automotive thermoplastic scrap into appearance automotive interior parts has been developed and shown to satisfy the following three requirements: 1) material performance 2) color appearance, and 3) economically sound. The technique developed is based on minimal separation of the colors into hues (groups of similar colors) and repigmenting to the desired color. The studies included computer formulations, laboratory verifications and plant runs. Plant runs were carried out to produce automotive interior doors (base level S-truck) with polypropylene (PP) regrind and B-pillar 325 parts with acrylonitrile-butadiene-styrene (ABS) regrind at the Delphi - Adrian plant. Two colors, ruby red and medium gray, were selected because they are the most difficult colors to match. The results of the plant runs demonstrated that color matching can be successfully achieved.

Recycling of automotive headliners has been carried out by grinding them and forming composites with isocyanate-based binders. Rear-seat-to-back-window trim panels have been prepared. Composites with 80-90 wt.% of scrap manufactured in plant runs exhibited mechanical properties comparable to the existing products. The rear-seat-to-back-window trim panel composites were produced by compression molding ground scrap-binder pre-preg sheets for 30 seconds at moderate temperatures, with no postcuring. This is the best indication that the utilization of the scrap headliners is both technically and economically sound. The plant runs have confirmed the feasibility of production of large parts with relatively complex shapes such as headliners. The adhesion of decorative materials to the composite substrates was excellent. More importantly, the decorative materials can be applied to the substrate during compression molding without any additional adhesive.