Plasticizer production figures

Waste plastics are con osed primarily of low-density polyethylene (LDPE) and high-density polyethylene (HOPE) products. These two types make up nearly 60% of aU plastic production. Figure 6.9 denotes the (Ustribution of waste plastics by type [42]. Because plastics are made from hydrocarbons, they tend to have very high energy values as noted in Table 6.11. These values conq>are well with fuel oil and are considerably higher than most coals and TDF [42,43]. 

In addition to polystyrene and high-impact polystyrene there are other important styrene-based plastics. Most important of these is ABS, with a global capacity of about 5 X 10 t.p.a. and production of about 3 X 10 t.p.a. The styrenic PPO materials reviewed in Chapter 21 have capaeity and production figures about one-tenth those for ABS. Data for the more specialised styrene-acrylonitrile copolymers are difficult to obtain but consumption estimates for Western Europe in the early 1990s were a little over 60000 t.p.a. 

Figure 2-5A. Lined-steel pipe and fittings for corrosive service. By permission. Performance Plastics Products.

From ships to submarines to mining the sea floor, certain plastics can survive sea environments, which are considered more hostile than those on earth or in space. For water-surface vehicles many different plastic products have been designed and used successfully in both fresh and the more hostile seawater. Figure 2-55 is an example where extensive use is made using unreinforced and reinforced plastics meeting structural and nonstructural product requirements. Included are compartments, electronic scanners, radomes, optically transparent devices, food storage and dispensing containers, medical products, buoyant devices, temperature insulators, and many more. 

The flexibility of some plastics can be improved by the addition of small molecules called plasticizers. For example, pure PVC turns brittle and cracks too easily to make useful flexible plastic products. With an added plasticizer, however, PVC can be used to make seat covers for automobiles, raincoats, garden hoses, and other flexible plastic objects. Plasticizers must be liquids that mix readily with the pol Tner. In addition, they must have low volatility so that they do not escape rapidly from the plastic. Dioctylphthalate is a liquid plasticizer that is formed by condensing two alcohol molecules with one molecule of phthalic acid, as illustrated in Figure 13-10. 

Figure 18.4. Example of technology analysis, e.g., 5% in rubber and plastic products means that 5% of the investments in a central electrolyser are produced in the rubber and plastic products sector in economic terms.

Possible Roles of insoluble Carbohydrates in Texture Development. Based on data obtained frcm soy isolate-soy hull blend texturization experiments, insoluble carbohydrates and crude fiber play an important role in modulating the morphology of final texturized products (Figures 11-14). Insoluble carbohydrates, because of their plastic response to deformation, control the type of alveolation developed during processing. 

In order to select materials that will maintain acceptable mechanical characteristics and dimensional stability one must be aware of both the normal and extreme thermal operating environments to which a product will be subjected. TS plastics have specific thermal conditions when compared to TPs that have various factors to consider which influence the product s performance and processing capabilities. TPs properties and processes are influenced by their thermal characteristics such as melt temperature (Tm), glass-transition temperature (Tg), dimensional stability, thermal conductivity, specific heat, thermal diffusivity, heat capacity, coefficient of thermal expansion, and decomposition (Td) Table 1.2 also provides some of these data on different plastics. There is a maximum temperature or, to be more precise, a maximum time-to-temperature relationship for all materials preceding loss of performance or decomposition. Data presented for different plastics in Figure 1.5 show 50% retention of mechanical and physical properties obtainable at room temperature, with plastics exposure and testing at elevated temperatures. 

DeMan and Beers (1987) have reviewed the factors that influence the formation of three-dimensional fat crystal networks. The fat crystal networks in plastic fats (Figure 8-44) are highly thixotropic, and mechanical action on these products will result in a drastic reduction of hardness. 

The Italian association for plastics processors, Unionplast, has been collecting figures for many years with the aim of devising a feasible recovery and recycling system for end-of-life plastic products, and has carried out a market survey specifically regarding PVC pipes and pipe-fittings. This article provides details of the association s findings. UNIONPLAST... 

About 50% of the present world-wide plastics production (>200 Mt/a) is based on polyethylene and polypropylene. When polystyrene is included, this percentage rises to 60%. With regard to their total production volumes, polyolefin materials thus are among the top 10 of all products generated in chemical industry. Major producers of polyethylene and polypropylene are shown, together with their production capacities, in Figure 4. 

FIGURE 1-9 Growth of US plastics production (with approximate dates of the commercial introduction of... 

The amount of plastic waste generated is still considerably less than that of plastics produced in numerous applications (building, furniture, appliances) plastics meet longterm requirements before their disposal and therefore do not yet occur in the waste stream in big quantities. The majority of plastic wastes are found in municipal solid waste (MSW), as well as in waste streams arising in distribution, agriculture, construction and demolition, furniture and household ware, automotive, electronic and electrical, or medical applications. For a number of years the APME has ordered studies to be made that compile inventories of on the one hand production figures, on the other waste arising, by resin, country, and application and activity. 

While the relatively young polymer industry was learning much from the modification of natural polymers, production figures were small. As the purely synthetic polymers came on stream, the range of valuable applications for plastic materials rapidly increased. Today, the annual mass of polymeric... 

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