Plastics developments since

The rapid rise of the plastics industry since World War II may be attributed to a number of factors. Foremost has been the fact that whilst many materials of construction have been subjected to continual increases in their price, the development of the petrochemicals industry and economies of scale have, for most of the time, led to reductions in the prices of plastics materials. With the passage of time more and more products constructed from traditional materials have become cheaper to produce from plastics. Whilst economies of scale have probably almost reached their limits, and whilst the low profitability of many plastics-producing plants may cause companies to retard increases in plant and production, the trend of increased plastics usage seems bound to continue. 

Electric road vehicles have been reduced to insignificance, as mentioned already by, vehicles with combustion engines. Another electric vehicle — the electrically driven submarine — presented a continuous challenge to lead-acid battery separator development since the 1930s and 1940s. The wood veneers originally used in electric vehicles proved too difficult to handle, especially if tall cells had to be manufactured. Therefore much intense effort took place to develop the first plastic separators. In this respect the microporous hard rubber separator, still available today in a more advanced version, and a micro-porous PVC separator (Porvic I) merit special mention 28]. For the latter a molten blend of PVC, plasticizer and starch was rolled into a flat product. In a lengthy pro-... 

When a plastic material is subjected to an external force, a part of the work done is elastically stored and the rest is irreversibly (or viscously) dissipated hence a viscoelastic material exists. The relative magnitudes of such elastic and viscous responses depend, among other things, on how fast the body is being deformed. It can be seen via tensile stress-strain curves that the faster the material is deformed, the greater will be the stress developed since less of the work done can be dissipated in the shorter time. 

Over the years innovations in aircraft have given rise to more new plastic developments and have kept the plastics industry profits at a higher level than any other major market principally since they can meet different environmental and load conditions. Virtually all plastics have received the benefit of the aircraft industry s uplifting influence. Practically all conceivable top quality plastics are used to provide cost advantages and improvements... 

Starch-plastic composites contain a mixture of two very different types of materials (/) hydrophobic, petrochemical-derived polymers (PE, EAA) known to be highly resistant to degradation by living organisms, and (i7) a hydrophilic, natural polymer (starch) that is easily broken down by a wide array of organisms. In the process developed by Otey (3), these fundamentally incompatible materials are forced into an intimate mixture during production of the plastic film. Since... 

Polymer bonded explosives (PBXs) were developed to reduce the sensitivity of the newly-synthesized explosive crystals by embedding the explosive crystals in a rubber-like polymeric matrix. The first PBX composition was developed at the Los Alamos Scientific Laboratories in USA in 1952. The composition consisted of RDX crystals embedded in plasticized polystyrene. Since 1952, Lawrence Livermore Laboratories, the US Navy and many other organizations have developed a series of PBX formulations, some of which are listed in Table 1.2. 

The properties of polymers need constant refinement in order to meet the constantly increasing demands on plastic parts. Since the development of new polymers is steadily decreasing [1], deliberate modification of the properties of a base polymer by means of additives and/or blending with other polymers is becoming increasingly important. Herein lies the primary task of compounding. 

Wei Mon Industry Co. was established in 1987 to manufacturing concrete piping materials as well as contracting major civil infrastructure projects such as water supply pipelines, sewerage systems, and land developments. Since 1996, Wei Mon started to research and develop natural and environmentally-friendly products, including Biodegradable Plastic Products. 

Immunochemical methods for low molecular weight (<1000 D) environmental compounds, such as pesticides, nitro aromatics, and PAHs (polycyclic aromatic hydrocarbons) have been developed since more than 25 years (e.g. Hammock and Mumma, 1980 Hammock et al., 1990 Dankwardt, 2000). The most common method is the immunoassay, which is either carried out with (heterogeneous) or without (homogenous) separation steps. Heterogeneous formats that use microtitre plates, plastic tubes and/or membranes as solid supports are more commonly used. 

Electrical and electronic products such as computers, cell phones, TVs, and stereos are becoming a more visible part of the MSW. Some of the resins used in electronic products are PS, HIPS, ABS, PC, PP, PU, PV, PVC, polyamides, phenol formaldehyde, and blends of some of these polymers. Several technologies are being developed for the separation of different plastic types. Since the electronic parts are made from many engineering plastics, and with many different additives, it is more difficult to identify and separate the individual resins. 

This chapter first gives an overview of cellulose raw materials and their molecular and supermolecular structures. The principles of shaping cellulose into fibres, films, and nonwovens by means of solution techniques are then outlined followed by a section on properties and market applications of these materials. Derivatives of cellulose are presented with special emphasis on thermoplastic cellulose esters, typical plasticizers, and promising reinforcing materials. Finally, recent developments and future prospects of cellulose materials are reviewed as far as the above applications are concerned. This book does not cover the important applications of cellulose and ligno cellulose fibres for reinforcing thermoplastics, like wood plastic composites (WPC) and natural fibre reinforced plastics (NFRP), since in these cases cellulose does not substitute a thermoplastic. 

Industries) in Cheshire, came across the same white, waxy substance when they were heating ethene with another compound, called benzaldehyde, under high pressure. Eventually, chemists worked out how to produce the white solid, known as polyethylene , on demand. During the Second World War it was used secretly to insulate cables. The process of making poly(ethene) (its formal, systematic name) has developed since, making the plastic an extremely common and versatile substance. 

Moves to harmonise fire safety assessment for building products in Europe has sparked a major shake-up in the flammability testing and classification of polymer materials [2]. As far back as 1998, over 30 tests were in use and more have been developed since then. The most radical change will be the introduction of the Single Burning Item for class B, C and D materials of intermediate combustibility, including most plastics. 

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