Alloyed Plastic

Since the first plastic cellulosic was produced in 1868, there has been an evergrowing demand for specially compounded plastics. Using a post-reactor technique, plastics can be compounded by alloying or blending polymers in addition to using additives such as colorants, flame retardants, heat or light stabilizers, lubricants, fillers, and/or reinforcements (Fig. 6-6). With reinforcements the resulting reinforced compounds are usually referred to as reinforced plastics (RPs). 

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Liquids. Liquids usually are moved through pipelines (qv) by pumps. Special alloys, plastic pipe and liners, glass, and ceramics are widely employed in the chemical industry for transport of corrosive hquids. Care is required in making the connections, to prevent exposure of unprotected metal such as flanges and bolts to the corrosive material inside the piping. 

The development of new polymer alloys has caused a lot of excitement in recent years but in fact the concept has been around for a long time. Indeed one of the major commercial successes of today, ABS, is in fact an alloy of acrylonitrile, butadiene and styrene. The principle of alloying plastics is similar to that of alloying metals - to achieve in one material the advantages possessed by several others. The recent increased interest and activity in the field of polymer alloys has occurred as a result of several new factors. One is the development of more sophisticated techniques for combining plastics which were previously considered to be incompatible. Another is the keen competition for a share of new market areas such as automobile bumpers, body panels etc. These applications call for combinations of properties not previously available in a single plastic and it has been found that it is less expensive to combine existing plastics than to develop a new monomer on which to base the new plastic. 

Chemicals and materials are vital components of today s technological world, which has slowly evolved from the use of stone axes and bearskins to the development of satellites, antibiotics, alloys, plastics, and composites. This development is impressive but required thousands of years. If the frontiers of chemistry can expand far enough to include material design, the coming progression of technology will be much more rapid. 

There are also colloidal "sols in which dispersed and dispersion mediums are solids (Eg alloys, plastics, glass, some minerals, etc) Refs 1)J. Alexander, "Colloid Chemistry, Theoretical and Applied , 6 volumes, Van Nostrand, NY (1926-1946) 2)W.K.Lewis, L.Squires G.Broughton, "Industrial Chemistry of Colloidal and Amorphous Materials , Macmillan, NY (1943) 3)H.B.Weiser, "Colloid Chemistry , A Textbook, Wiley, NY (1949) 4)A.E. Alexander St P.John-... 

Because of the extremely wide variety of reactions, educts, products, and process conditions, a sufficiently broad spectrum of materials is required to realize suitable microdevices for chemical processes. Metals and metal alloys, plastics, glass, ceramic materials, semiconductor materials like silicon, and various auxiliary materials for sealing, surface treatment, etc. have been successfully applied for realizing microreaction devices. 

A promising area is the design of modem ceramic and glass ceramic materials based on high purity elementorganic compounds Si(OR)4, Al(OR)3, B(OR)3, etc.), because traditional materials (metals, metal-based alloys, plastics, etc.) do not meet contemporaiy technical requirements to products designed to operate under extreme conditions. 

Battelle Pacific Northwest National Laboratories (PNNL, Richland, WA) are developing microreactors that produce synthesis gas. These reactors can be mass-produced to yield efficient, compact and cost-effective systems, and they have been made from copper, aluminum, stainless steel, high-temperature alloys, plastics and ceramics. Conventional technologies cannot take full advantage of the intrinsically rapid surface reactions involved in the catalytic conversion of hydrocarbon fuels, but microreactors with integrated catalyst structures can61. 

Kydex [Rohm Haas]. TM for a thermo-formed acrylic polyvinyl chloride alloy plastic sheet. 

The (C)RM has to fulfil a defined task. Therefore, the material must be accurately chosen. The selection of the material itself is easy when pure substances for calibration or identification purposes are considered. For artificial materials such as manufactured products e.g. steel, alloys, plastics, ceramics etc., the manufacturing process may be the defining tool. Where natural matrix materials are concerned, the selection of the (C)RM passes through a careful study of the objective of the method to be validated. A method for contaminated soil analysis has to cover soils of various origin, the CRM(s) to validate... 

CHEMICAL PROPERTIES Polymerizes in sunlight incompatible with copper, alloys, plastics and oxidizing agents FP (5°C) LFL (9%) UFL (15%) AT (986 C). 

Stainless steel can be supplied with a batch-specific material certificate that details the exact composition of the alloy. Plastics and rubber components cannot be so easily defined. For this reason, certification of particular polymers is rarely provided on a batch-by-batch basis, but by generic assurance that relates to a particular grade of material from a particular supplier. 

A variety of materials are used in food processing such as stainless steels and aluminum alloys. Plastics and other materials such as brass and bronze may be used. Plastics and other metals may be used. Lead and cadmiiun plated materials impart toxicity to foods. Food contact surfaces must be smooth, no-adsorbent, nonleaching, and insoluble in the food. 

Coatings for buildings are solvent- or waterborne. They include coatings that can protect all materials used in building and construction work (e.g., wood, steel, light metals and alloys, plastics, concrete, plaster) against corrosion and decomposition they can also give a decorative appearance. 

P-group (plastic) long chip building ferrous materials, steel K-group nonferrous metals, cast iron, AlSi alloys, plastics, wood... 

In Chapter 17, we vnll look more dosely at materials that commonly are used in various engineering applications. We will also discuss some of the basic physical characteristics of materials that are considered in design. We will examine the application and properties of common solid materials such as metals and their alloys, plastics, glass, and wood and those that solidify over time such as concrete. We will also investigate in more detail basic fluids such as air andvrater. 

Goodloe is available most commonly in 316 stainless steel, but also in carbon steel, aluminum, alloys, plastic, Kynar, and Teflon. Good-loe is avEiilable from Glitsch Inc. and from ACS. 

Data for polyester blends and alloys plastics are found in Figures 4.143—4.158. 

Nipol Polyblends NBR/PVC (30-50 %) elastomeric alloys plasticized or not Nippon Zeon Co., Ltd. 

Super Samson Alloy, Plastic mold steel with high-mechanical properties. Carpenter Technology Corp. 

Biomaterials Substances, including metal alloys, plastic polymers, and living tissues, used to replace body tissues or as implants. 

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