Fabricating products major families

Of this family of products, triaryl phosphates (TAP) and alkyl diaryl phosphates (ADP) are the two important categories of FR plasticizers for PVC. Trialkyl phosphates are considered too volatile for most vinyl processes, and are more commonly found in other applications, such as leveling agents or antifoam additives. In vinyl, TAP and ADP plasticizers are used to flame-retard thin films and laminates for articles such as wall covering, tarpaulins (transportation), and vinyl-coated furniture fabric. Another major application area is in vinyl for electrical insulation in wire and cable. In addition to these applications, phosphate esters are used as functional fluids for hydraulic equipment (metal industries, power generation, and aircraft hydraulic systems) and as additives in formulated lubricant systems. As flexible vinyl composites are usually defined by their additives, when formulated correctly, phosphate esters can help produce a very cost-efficient vinyl composite capable of very low smoke and flammabihty. In nearly all markets, phosphate esters are valued primarily for their FR properties, and the distinction from function and plasticization is sometimes obscured. 

Advanced composites represent another major growth market. It is expected to reach 10 billion by the end of the next decade. Du Pont recently announced the formation of a new composites division to consolidate operations and business-planning functions. The company intends to participate in every step of the composites process, from the manufacture of reinforcing fibers and resins to the design and fabrication of finished products to replace metals in aeronautic, aerospace, and automative applications. Du Pont s families of engineering resins and industrial fibers give it an excellent springboard for this opportunity. 

Plastics are families of materials each with their own special advantages. An example is polyethylene (PE) with its many types include low density PE (LDPE), high density PE (HDPE), High molecular weight PE (HMWPE), etc. The major consideration for a designer and/or fabricator is to analyze what is required as regards to product performances and develop a logical selection procedure from what is available. 

The family of PKs, also called polyaryletherketones (PAEKs), consists of polyetheretherketone (PEEK), polyetheretherketone-ketone (PEEKK), polyetherketone (PEK), and polyetherketone-etherketone-ketone (PEKEKK). They share similar molecular structures based upon repeating ether and ketone groups in various ratios. Cost of the resins is high but, in RPs with high-performance fibers, there are many appfications in the aerospace and defense industries, electrical and atomic installations, and industrial and electronics products. Compoimds for injection molding are available, but the major area of apphcation is with thermoplastic prepreg materials, using mats, fabrics and/or continuous fiber. 

Fabrication of an enzyme-modified electrode, and indeed any biosensor, requires stepwise selection and integration of a number of complex components. First, the redox enzyme chosen must have the required selectivity for the analyte as well as a product that is detectable at the signal transducer (in this case the electrode surface). A search of the literature reveals that a relatively small number of enzymes have been reported as functional on biosensors, and two classes of enzymes (oxido-reductase and dehydrogenase) predominate. Notably, the oxido-reductase family, and glucose oxidase in particular, account for the majority of all reports in the literature. Other factors that complicate the choice of enzyme include the necessity for a derivatization procedure that does not destroy the active site of the enzyme. In some cases, proper orientation of the enzyme s active site must also be considered. Glutamate dehydrogenase, a protein whose conformation (and therefore activity) is dependent on electrostatic forces, has been... 

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