Melting molding system

As mentioned previously, the drug may be present in one of several forms in the final product. The advantages and disadvantages of each form have been discussed in both injection molding and melt extrusion systems. Solid dispersion systems may be more stable and more easily processed than solid solution systems, but solid solution systems may be produced that are transparent and have increased bioavailability of poorly soluble compounds. Figs. 3 and 4 show the X-ray diffraction patterns for a polymer film containing lidocaine. The absence of the lidocaine peaks in the extruded samples, and the reported... 

Ehnax, Stainless mold steel, Uddeholm EHesol, Catalysts, Albright Wilson Americas Elvaloy, Ethylene/ester/CO terpolymers, DuPont Elvamide, Nylon multipolymer resins, DuPont Elvanol, Polyvinyl alcohol, DuPont Elvax, EVA resins, DuPont Emamelt, Electromagnetic hot melts, Emabond Systems, Ashland Chemical Co. 

These improvement possibilities are not restricted to injection molds. Thus, in addition to the mold cavities for thermoplastic, thermoset, and elastomer processing, also extrusion molds, slides and jaws, ejector systems, melt control systems and return valves are treated with success. Also for the treatable types of mold materials, the frontiers have been pushed back in recent years. In addition to typical mold steels, nonferrous metals like aluminum or copper alloys can be optimized through different surface and coating technologies. 

Injection Mold Melt Delivery System (Runners and Gates)... 

These ahoys are used as fuses, sprinkler system ahoys, foundry pattern ahoys, molds, dies, punches, cores, and mandrels where the low melting ahoy is often melted out of a mold. The ahoys are also used as solders, for the repHcation of human body parts (see Prosthetic devices), and as filler for tube bending. Lead—iadium ahoys are often used to joia metals to glass. 

An iajection mol ding machine is operated by hydrauHc power and equipped with an electric motor and hydrauHc pump. The maximum hydrauHc oil pressure is ca 14 MPa (2000 psi). A hydrauHc cylinder opens and closes the mold and holds the mold closed duriag iajection another cylinder forces the screw forward, thereby injecting the melt iato the mold. A separate hydrauHc motor turns the screw to plasticate, homogenize, and pressurize the melt. Control of these movements is a combined function of the hydrauHc and electrical systems (35—37). 

As reviewed in other chapters, different plastics have different melt and flow characteristics. What is used in a mold design for a specific material may thus require a completely different type of mold for another material. These two materials might, for instance, be of the same plastic but use different proportions of additives and reinforcements. This situation is no different than that of other materials like steel, ceramics, and aluminum. Each material will require its own cavity shapes and possibly have its own runner system. 

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