Moldability

Large quantities of zinc are used to produce die castings, which are used extensively by the automotive, electrical, and hardware industries. An alloy called Prestal(R), consisting of 78 percent zinc and 22 percent aluminum, is reported to be almost as strong as steel and as easy to mold as plastic. The alloy said to be so moldable that it can be molded into form using inexpensive ceramics or cement die casts. 

Copper, with its high heat conductivity, resists frictional heat during service and is readily moldable. It is generally used as a base metal, at 60—75 wt %, whereas tin or zinc powders are present at 5—10 wt %. Tin and zinc are soluble in the copper, and strengthen the matrix through the formation of a soHd solution during sintering. 

Impression Waxes. Impression waxes include those waxes used to obtain a negative cast of the mouth stmcture (impression waxes), waxes used to estabhsh tooth articulation (bite-registration waxes), and waxes used to detect tooth interference and high spots or improper fit of denture bases (disclosing waxes). They must be plastic and moldable at mouth temperatures, and chill to a stiU nonplastic mass upon cooling within a few degrees below mouth temperature. 

Amalgam restorations are prepared by mixing a powdered alloy with mercury to form a plastic moldable mass that is packed or condensed iato the prepared cavity. The cavity is designed to provide mechanical retention, maximum marginal mass, support to absorb the functional stresses transmitted through the restoration, and maximum protection to the remaining tooth stmcture. The restoration reestabUshes the normal tooth anatomical form and function. 

The PAI resin is utilized for small, simple parts. Because of its stiff melt flow, the resin is available in compression moldable powder. Grades include neat, filled, and glass-reinforced resins it is also available in solution for use as an enamel. Because of high prices ( 33—44/kg) the market is limited, estimated at 150—300 tons for the mol ding resin. Resins competing with PAI include PEI, polyethersulfones, and thermoset resins. 

Thermoplastic Condensation Polyimides. These include General Electric s Ultem Resin and Amoco s Todon polyamideimide although the latter is no longer offered as injection moldable pellets, but as compression moldable powder and in solution. Another resin, P-84, originally developed by Upjohn but now made by Lenzing (Austria), is based on benzoquinone dianhydride and aromatic isocyanates. 

Moldable with inserts like the organic plastics... 

Moldable holes and inserts can complicate molding and may require extra postmolding operations. Thus, the most economical designs are those that minimize the number of holes. With many plastics, both external and internal threads can be molded, but sharp V threads should be avoided because they can cause the plastic to bridge, resulting in incomplete thread fill. Rounded or modified buttress threads will allow improved thread fill. 

The ease and economy of manufacturing gears, cams, bearings, slides, ratchets, and so on with injection-moldable TPs have... 

Major shape Hollow Simple Moldable Constant Structure Few Moldable Hollow Moldable Simple Moldable... 

Shape limitations None Flexibility of the bag Surface of revolution Constant cross-section Moldable Moldable... 

Purchase Description for Explosive, Plastic Bonded, Injection Moldable, PBXC-303 (PBXN-301) , NAVORD WS 12612 (1972) 92) B.M. 

Such soft-touch materials are usually TP Vs or thermoplastic elastomers (TPEs) which combine the moldability of thermoplastics in the melt state with elasticity, lower hardness, fracture resistance, and surface characteristics of elastomers. However, plastics and elastomers respond differently to mechanical stress. Hence, both rheological behavior and mechanical strength will to a large extent depend on the morphology of the blend which may change with change in the composition. 

Uses Ethylbenzene is used primarily to make styrene. Styrene is used to make polystyrene, a low-cost and versatile polymer. It is also copolymerized with other vinyl monomers to make rubber (SBR) and moldable plastics (ABS). 

Acrylic textile fibers are primarily polymers of acrylonitrile. It is copolymerized with styrene and butadiene to make moldable plastics known as SA and ABS resins, respectively. Solutia and others electrolytically dimerize it to adiponitrile, a compound used to make a nylon intermediate. Reaction with water produces a chemical (acrylamide), which is an intermediate for the production of polyacrylamide used in water treatment and oil recovery. 

The low thermal stability of many poly(iminocarbonates) limits the use of melt fabrication techniques such as injection molding or extrusion. For example, among all six polymers tested, only poly-(Dat-Tyr-Hex) and poly(CTTH) had low enough softening points to be compression moldable without a significant degree of thermal decomposition. ... 

The PBE dendron has a glass transition at about 40 °C and is soluble in various organic solvents (e.g., THF, acetone, toluene). It is therefore a moldable, thermoplastic, film-forming material. This practical feature is maintained for the lanthanide-cored dendrimer complexes. The complexes are partially miscible with poly(methyl methacrylate), affording transparent luminescence compositions by mixing in solvent. 

Poly(HASCL) (i.e. PHB and poly(3HB-co-3HV)) are typical thermoplastic polymers, which become fluid and moldable above their melting points, whereas poly(HAMCL)s generally are elastomers with low melting points. PHB has been reported to show a relatively high melting temperature of about 180°C, while the Tg of this polymer is approximately 9 °C [21,52,53]. Incorporation of 3HV-comonomer units into PHB decreases both the Tm as well as the Tg significantly. Poly(3HB-co-3HV), containing up to 28 mol% 3HV, has a Tm of about 102°C and a Tg of -8°C, respectively [21,52,53]. 

Chiechi RC, Weiss EA, Dickey MD, Whitesides GM (2008) Eutectic gallium-indium (EGaln) a moldable liquid metal for electrical characterization of self-assembled monolayers. Angew Chem Int Ed 47(1)442-144... 

Klajn, R. Bishop, K. J. M. Fialkowski, M. Paszewski, M. Campbell, C. I Gray, T. E Grzybowski, B. A. 2007. Plastic and moldable metals by self-assembly of sticky nanoparticle aggregates. Science 316 261-264. 

The Augusta facility produced plastics, including Amodel, a hard but moldable high-performance nylon. Amodel is manufactured by passing a solution of diamines and dicarboxylic acids through a series of reactors. The reaction is completed in an extruder, and the material is then formed and cooled into solid pellets. 

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