Reprocessed plastic

The Japan Small Business Corp. has developed a waste plastics reprocessing system to convert plastics in domestic waste into fuel oil. The system uses an oil... 

Mixed phosphate ester-titanium complexes, 25 92 Mixed plastics, reprocessing of,... 

Plastics reprocessing is carried out in modem large scale plants strategically located near centres of population density where reasonable quantities of feedstock exist. As a result, one finds plastics reprocessors in Vancouver British Columbia, near Calgary, Alberta, the Toronto- Ontario area and in proximity to Montreal Quebec. Facilities are lacking in the prairie provinces and in Atlantic Canada. Atlantic Canada however does have some material reprocessed in the Eastern United States. 

The amount of plastics recycled in 1998 was 260,000 tons from durable goods, and 950,000 tons from containers and packaging, for a total of 1.2 million tons. Plastics News reported sales of North American plastics recyclers and brokers totaled 1.74 billion in 2000, with 29 percent of that post-consumer plastics and the remainder post-industrial and brokered plastics. The total amount of plastics reprocessed was 5.54 biUion pounds. ... 

Commonly accepted practice restricts the term to plastics that serve engineering purposes and can be processed and reprocessed by injection and extmsion methods. This excludes the so-called specialty plastics, eg, fluorocarbon polymers and infusible film products such as Kapton and Updex polyimide film, and thermosets including phenoHcs, epoxies, urea—formaldehydes, and sdicones, some of which have been termed engineering plastics by other authors (4) (see Elastol rs, synthetic-fluorocarbon elastol rs Eluorine compounds, organic-tdtrafluoroethylenecopolyt rs with ethylene Phenolic resins Epoxy resins Amino resins and plastics). 

Thermoplastic elastomers have now been available for over 30 years and the writer recalls organising a conference on these materials in 1969. In spite of considerable publicity since that time these materials still only comprise about 5-10% of the rubber market (equivalent to about 1-2% of total plastics consumption). It is important to appreciate that simply being a thermoplastic material (and hence being processed and reprocessed like a thermoplastic plastics material) is not enough to ensure widespread application. Crucially the material must have acceptable properties for a potential end-use and at a finished product price advantageous over other materials. 

Plastics are long chain, high molecular weight polymers which can be formed under application of heat and pressure into desired shapes and contours by a variety of processing techniques. Plastic resins are classified either as thermoplastics, if the material can be reprocessed under heat and pressure, or as thermosets if the material, once formed, cannot be reprocessed. 

Since the system is processed as thermoplastics are processed, its reprocessability was studied under repeated cycles of extrusion in the MPT. Results of reprocessability studies are shown in Table 5. It is evident that after the first cycle viscosity increased slightly, which may be due to the orientation effect. In the subsequent cycles viscosity remained almost constant. Therefore, it is concluded that the zinc stearate plasticized zinc salt of m-EPDM is melt processable just as thermoplastics. 

Brief details are given of two proposed resolutions on the subject of pyrolysis of waste plastic. The first states that pyrolysis and other methods of chemically reprocessing post-consumer plastics is a suitable way of diverting waste from landfills. The second resolution, supported by environmentalists, states that pyrolysis only recovers plastic s energy value, and should not be viewed as recycling. 

Uses Plasticizer for lacquers, plastics, cellulose esters, and vinyl resins heat-exchange liquid carbonless copy paper systems in aircraft hydraulic fluids solvent extraction of metal ions from solution of reactor products uranium extraction and nuclear fuel reprocessing pigment grinding assistant antifoaming agent solvent for nitrocellulose and cellulose acetate. 

Thermoplastics, which account for 87% of plastics sold, are the most recyclable form of plastics because they can be remelted and reprocessed usually with only minor changes in their properties. Five resins are commonly used in consumer packaging applications. 

Since about 1990 plastics recycling has been a growing and developing business. It is here to stay in one form or another. Collection and separation are the main problems. PET and HDPE by far are the main plastics that are most easily recycled. These two polymers are used as containers and easily reprocessed. Plastic films (especially LDPE) have a potential for recycling increases, but this form of plastic material is not as easily collected and stored. 

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