Extrusion casting

Among the more than several uses for polyethers in ordn application is as a binder for extrusion cast expls (Ref 3), and in a caseless propint charge where the charge is used as an ammo element (Ref 5). Also, some development work on the use of Poly acetal resins (polyform aldehyde)1 as a fuel has been done by Singhal T ien yief 7)... 

New Poly ester-Poly ether Binder for Extrusion-Cast Explosives , UCRL-50541, UAEC, Univ of Calif (1968) Ibid, NuclSciAbst 23 (9), 17314 (1969) CA 71,71343 (1969)... 

Polypropylene (PP) films were first produced by extrusion casting. Polymer is extruded through a slit or tubular die and quenched by cooling on chill rolls or in a water bath. Cast films can be sealed over a wide range of temperatures and do not shrink in a steam autoclave, Polymers with melt flow rates below 5 dg/min are usually used to maintain the stability of the extra date. Higher clarity films are produced using random copolymers. 

The particular case of polymer-oligomeric compositions creates new technological possibilities such as the preparation of foamed articles directly at the place of utilization by foaming solutions or pastes at room temperature or sl tly elevated temperatures. It als) leads to a considerable reduction of enei consumption as cOTii ed to traditional processing methods (extrusion, casting and pressing). 

Manufacturing process Extrusion-cast Solution-cast... 

Film Preparation. Extrusion cast films of each barrier resin, approximately 7-10 mil in thickness, were produced by coextrusion as three-layer structures, 30 to 32 mils thick, between either HDPE or PP sacrificial skins. 

Compression molded control films of VDC copolymer, 1-2 mil in thickness, were prepared by reheating extrusion cast films between the platens of a molding press. 

Efforts to orient VDC copolymer films resulted in uneven stretching. Adjusting orientation conditions yielded no apparent improvements in orientability. The non-uniform orientation of this film is attributed to the development of sufficient crystallinity in the extrusion cast film prior to orientation. 

Compression molded film Extrusion cast film Biaxially oriented - 2.5 x 2.5... 

The effect of orientation on amorphous barrier resins SELAR PA 3426 and XHTA-50A are shown in Table III. The measured oxygen permeability of 1.4 cc-mil/100 in 24 hr. atm for unoriented extrusion cast SELAR PA 3426 film is reduced by 19% upon uniaxial orientation, while the permeability of biaxially oriented films are 28% lower than that of extrusion cast film. Similarly, the decrease in oxygen permeability with 2X and 2.5X uniaxial orientation in XHTA-50A are 5% and 9% respectively, from the measured value of 3.1 cc-mil/100 in 24 hr. atm for unoriented film. The corresponding reduction in permeability with 2X x 2X biaxial orientation is 12%. 

Selar PT Resins. Sheet extrusion, cast and blown film, and extrusion coat-... 

Film Processing Methods Blown, extrusion, cast, and coextruded film, or blends with other resins. 

Figure 11.2 Biaxialty oriented extrusion cast film machine and typical temperature conditions used during biaxial orientation fllm casting. Reproduced from ref. 71 with permission of Elsevier.

A. Christie, Flat Die Extrusion Cast Film (Coating Laminating, Tappi, 2009)... 

Currently, Nation is available in two forms extrusion-cast membranes and polymer dispersions. Nation polymer dispersions are used in the formulation of GDEs and reinforced membranes. Nation 117 is 7 mils thick (1 mil = 25.4 ttm) but can be obtained thinner. Table 1 illustrates the current offering of Nation from DuPont [75]. A number of excellent review articles exist that describe the structure, morphology, physical properties, and applications ofNation [56,76-81]. 

PMMA is a thermoplastic that can be formed by injection molding or extrusion. Casting monomer or monomer-polymer syrup and polymerizing can also form PMMA. PMMA plates, commonly known as Plexiglass or Lucite, are formed this way. 

As the polymer is polar, it should be dried before processing. It can be processed by injection molding into a variety of parts. SAN can also be processed by blow molding, extrusion, casting, and thermoforming. ... 

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