Novel Plasticizers

The insulating value and mechanical properties of rigid plastic foams have led to the development of several novel methods of buUding constmction. Polyurethane foam panels may be used as unit stmctural components (220) and expanded polystyrene is employed as a concrete base in thin-sheU constmction (221). 

Other. Because a foam consists of many small, trapped gas bubbles, it can be very effective as a thermal insulator. Usually soHd foams are used for insulation purposes, but there are some instances where Hquid foams also find uses for insulation (see Eoamed plastics Insulation, thermal). Eor example, it is possible to apply and remove the insulation simply by forming or coUapsing the foam, providing additional control of the insulation process. Another novel use that is being explored is the potential of absorbing much of the pressure produced by an explosion. The energy in the shock wave is first partially absorbed by breaking the bubbles into very small droplets, and then further absorbed as the droplets are evaporated (53). 

An extremely wide range of surface finishes is possible which may not only simulate non-plastics materials but in addition produce novel effects. 

On his return home in 1911, Honda was appointed professor of physies at the new Tohoku Imperial University in Sendai, in the north of Japan this institution had been established only in 1906, when the finance minister twisted the arm of an industrialist who had made himself unpopular because of pollution eaused by his copper mines and extracted the necessary funds to build the new university. A provisional institute of physical and chemical research was initiated in 1916, divided into a part devoted to novel plastics and another to metals. This proved to be Honda s lifetime domain he assembled a lively team of young physicists and chemists. In the same year, Honda invented a high-cobalt steel also containing tungsten and chromium, which had by far the highest coercivity of any permanent-magnet material then known. He called it KS steel, for K. Sumitomo, one of his sponsors, and it made Honda famous. 

The preparation and properties of a novel, commercially viable Li-ion battery based on a gel electrolyte has recently been disclosed by Bellcore (USA) [124]. The technology has, to date, been licensed to six companies and full commercial production is imminent. The polymer membrane is a copolymer based on PVdF copolymerized with hexafluoropropylene (HFP). HFP helps to decrease the crystallinity of the PVdF component, enhancing its ability to absorb liquid. Optimizing the liquid absorption ability, mechanical strength, and processability requires optimized amorphous/crystalline-phase distribution. The PVdF-HFP membrane can absorb plasticizer up to 200 percent of its original volume, especially when a pore former (fumed silica) is added. The liquid electrolyte is typically a solution of LiPF6 in 2 1 ethylene carbonate dimethyl car-... 

Worldwide suppliers with bioengineering capabilities are displacing established polymers with cost-effective and higher performing plastics. An explosion of novel polymers has been made by enzymatic control. The use of enzymes for polymerization has drastically altered the landscape of polymer chemistry. Processors can request specific properties for each application as opposed to the usual making do with what is available. The supplier can deliver to the processor desired properties requested. 

Because melts have different properties and there are many ways to control processes, detailed factual predictions of final output are difficult to arrive. Research and hands-on operation have been directed mainly at explaining the behavior of melts or plastics like with other materials (steel, glass, and so on). Modem equipment and controls are overcoming some of this unpredictability. Ideally, processes and equipment should be designed to take advantage of the novel properties of plastics rather than to overcome them. 

These novel organic polymers were not developed solely for the CW or BW treatment market but are for much wider application. These same value-adding process additives are regularly incorporated into products for industrial and domestic cleaning, concrete, pulp and paper, metal finishing, paints and surface coatings, wastewater, seawater distillation, drilling muds, secondary oil-recovery, plastics extrusion, fibers, rubbers, and a host of other areas. 

A novel non-petroleum based biodegradable plastic produced from sugar based agricultural raw materials as sweet sorghum, sugarcane and molasses, having potential properties comparable with conventional or synthetic plastics, is under development and could lower the contribution of plastic wastes to municipal landfills at about 20% of the total waste by volume and 10% by weight and can achieve a satisfactory for the environmental imperative. 

TPEs prepared from rubber-plastic blends usually show poor high-temperature properties. This problem could be solved by using high-melting plastics like polyamides and polyesters. But, often they impart processing problems to the blends. Jha and Bhowmick [49] and Jha et al. [50] have reported the development and properties of novel heat and oil-resistant TPEs from reactive blends of nylon-6 and acrylate rubber (ACM). The properties of various thermoplastic compositions are shown in Table 5.4. In this kind of blend, the plastic phase forms the continuous phase, whereas... 

Jha A., Dutta B., and Bhowmick A.K., Effect of fillers and plasticizers on the performance of novel heat and oil-resistant thermoplastic elastomers from nylon-6 and acrylate rubber blends, J. Appl. Polym. Sci., 74, 1490, 1999. 

Experience with chlorofluorocarbons (CFCs), insecticides such as DDT, herbicides and fertilizers has taught us that extended stability of these products may lead to unexpected harmfiil results. An important challenge will be to develop novel products that have a limited stable life and then decompose so that they do not persist in this environment. Examples are the development of plastic packages that decompose and degrade with time and of agricultural chemicals that do not harm unintended targets and are not overly persistent. 

To realize micro reactors with sensing and surface-control structures, the underlying fabrication methods have to go beyond MEMS and classical micro machining [75]. Plastic and glass manufacture and also novel innovative methods such as soft lithography have to be developed further and applied. 

The structure and the formation of foams are discussed from a theoretical point of view. The conditions for foam stability are stressed and a novel hypothesis is presented on the action of hydrocolloids as plasticizers of the walls of foams. 

G. Pritchard, Novel and Traditional Fillers for Plastics Technology and Market Developments, Rapra Technology Industry Analysis Report, Rapra Technology Ltd, Shaw-bury (1999). 

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