Poly wastes

Other Plastics. A relatively small amount of poly(vinyl chloride) goes into packagiag appHcations and appears in municipal soHd waste (25). 

Cationic monomers are used to enhance adsorption on waste soHds and faciHtate flocculation (31). One of the first used in water treatment processes (10) is obtained by the cyclization of dimethyldiallylammonium chloride in 60—70 wt % aqueous solution (43) (see Water). Another cationic water-soluble polymer, poly(dimethylarnine-fi9-epichlorohydrin) (11), prepared by the step-growth... 

There are numerous misconceptions about the sources of various chemical elements in waste, particularly those that are potential acid formers when the waste is incinerated or mechanically converted and used as a refuse-derived fuel. For example, it is often mistakenly stated that the source of chlorine in waste, hence a potential source of HCl emissions, is poly(vinyl chloride). The relative contents of selected, potentially acid-forming elements in the organic portion of a sample of waste collected from various households in one U.S. East Coast city is given in Table 2 (17). In this city, a chief source of chlorine in the waste is NaCl, probably from food waste. 

Gutcho, Waste Treatment with Poly electrolytes Noyes Data Corp., Park Ridge, NJ, 1972. 

Substantial quantities of UPVC are also used for blow moulded containers for such diverse materials as consumable liquids such as fruit squashes, liquids for household use such as detergents and disinfectants, cosmetics and toiletries, and pharmaceuticals. For most of these applications UPVC is in competition with at least one other polymer, particularly poly(ethylene) terephthalate (Chapter 25), polyethylene (Chapter 10), polypropylene (Chapter 11) and, to a small extent, the nitrile resins (Chapter 15). The net result is that in recent years there has been some replacement of PPVC in these areas, in part because of problems of waste disposal. 

In America there are promising signs for certain polymers. For example, poly(ethylene terephthalate) drinks bottles can be cleaned and recycled to give an acceptable grade of PET resin in a process that is economically viable. The recycled polymer is used as carpet fibre, furniture stuffing, or insulation. Waste nylon can also be recycled profitably. 

The quantity of these materials is relatively small compared with the amount of waste high-density poly(ethylene) produced each year. Containers made from HDPE are widely used for detergents, oil, and antifreeze, and enormous amounts of material are used in disposable applications aimually. In principle recycled poly(ethylene) could be used for drain pipes, flower pots, dustbins, and plastic crates. The problem remains, however, that economics do not favour recycling of these polymers and in the absence of Government intervention little or nothing can be done to alter commercial attitudes towards recycling. 

On land, too, there are changes in the way plastics are disposed of. In the UK some local authorities are actively promoting recycling of plastic bottles and poly(styrene) containers, for example by schemes where local residents place recyclable materials in designated boxes for refuse collectors. These boxes are taken to a Materials Reclamation Facility for final sorting of the plastics waste. 

Macromolecular Materials and Engineering 286, No.ll, 30thNov.2001, p.695-704 UV CURABILITY AND MECHANICAL PROPERTIES OF NOVEL BINDER SYSTEMS DERIVED FROM POLY(ETHYLENE TEREPHTHALATE)(PET) WASTE FOR SOLVENTLESS MAGNETIC TAPE MANUFACTURING. I. ACRYLATED OLIGOESTERS Farahat M S Nikles D E Alabama,University... 

Macromolecular Materials and Engineering 286, No.9, 28th Sept.2001, p.513-5 SYNTHESIS OE URETHANE OIL VARNISHES EROM WASTE POLY(ETHYLENE TEREPHTHALATE)... 

Polymer Recycling 3,No.3, 1997/98, p.173-80 UNSATURATED POLYESTER RESINS FROM POLY(ETHYLENE TEREPHTHALATE) WASTE SYNTHESIS AND CHARACTERISATION Abdel-Azim AA Mekewi M A Gouda S R Egyptian Petroleum Research Institute Ain Shams,University Egypt,Military Technical College... 

Techniques for chemical recycling of waste saturated polyesters, mainly poly(ethylene terephthalate) and of waste polyurethanes to produce polyurethanes are reviewed. 29 refs. Articles from this journal can be... 

The purpose of the study was to determine the optimum conditions of operation of pyrolysis equipment by the combined solution of equations relating to the technological and economic analysis of the process. The material considered was poly(methyl methacrylate) one of the most popular types of plastic waste. Articles from this journal can be requested for translation by subscribers to the Rapra produced International Polymer Science and Technology. 

Polymers for Advanced Technologies 6, No. 11, Nov. 1995, p.688-92 MAKING POLYMER CONCRETE AND POLYMER MORTAR USING SYNTHESISED UNSATURATED POLYESTER RESINS FROM POLY(ETHYLENE TEREPHTHALATE) WASTE Abdel-Azim A AA Attia IA Egyptian Petroleum Research Institute Carro,Ain Shams University... 

Reactive compatibilization is also carried out by adding a monomer which in the presence of a catalyst can react with one or both phases providing a graft copolymer in situ that acts as a compatibilizer. Beaty and coworkers added methyl methacrylate and peroxide to waste plastics (containing polyethylene [PE], polypropylene [PP], PS, and poly(ethylene terephthalate) [PET]). The graft copolymer formed in situ homogenized the blend very effectively [19]. 

Tipanna, M. and Kale, D.D., Composites of waste, ground rubber particles and poly(vinyl chloride). Rubber Chem. Technol., 70, 815, 1997. 

Anandhan, S., De, P.P., De, S.K., Swayajith, S., and Bhowmick, A.K., Thermorheological properties of thermoplastic elastomeric blends of nitrile rubber and poly(styrene-co-acrylonitrile) containing waste nitrile rubber vulcanizate powder, Kautsch. Gummi Kunst., 11, 2004. 

Perhaps the most interesting finding of our synthetic studies was that the interfacial preparation of poly(iminocarbonates) is possible in spite of the pronounced hydrolytic instability of the cyanate moiety (see Illustrative Procedure 3). Hydrolysis of the chemically reactive monomer is usually a highly undesirable side reaction during interfacial polymerizations. During the preparation of nylons, for example, the hydrolysis of the acid chloride component to an inert carboxylic acid represents a wasteful loss. 

In Japan the amount of waste poly(vinyl chloride) (PVC) has been sharply increasing since disposal of building materials such as pipe and roof liners with long service life has been started recently. It was estimated to be approximately one million tons in FY 2000, and it is predicted to increase further to approximately 1.8 million tons in FY 2020. Since the landfill sites run short and the incineration to reduce its volume produces dioxins and corrodes boiler tube by hydrogen chloride, development of a safe and inexpensive technology for the recycling of waste PVC is one of the most urgent issues. 

Poly(L-lysine) has also been suggested as a carrier for pepstatin, a specific inhibitor of the lysosomal proteinase cathepsin D, responsible for causing muscle-wasting diseases, such as muscular dystrophy [257],... 

Finally, a novel process has been described for efficient photoconversion of low-grade organic materials such as waste biomass into polyesters. In this process, dry biomass has been thermally gasified which resulted in gas mixtures composed primarily of CO and H2. Photosynthetic bacteria photoassimilated components of the synthesized gas into new cell mass. Under unbalanced culture conditions, when growth was limited by several nutrients, up to 28 % of the new biomass was found to be poly(3HB) [37]. 

When comparing fed-batch operated cultures it can be seen that the main difference between poly(3HB) and poly(3HAMCL) production that affect the process parameters is the lower cellular poly(3HAMCL) content, compared to the cellular poly(3HB) content. Not surprisingly, it has been reported that a low poly(3HAMCL) content decreases the productivity and yield and increases the costs for downstream processing and waste disposal [102]. 

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