Blow molding rigid packaging

The fifth and final section opens with a chapter on design of plastic parts then presents applications plastics in buildings and construction, infrastructure applications of fiber-reinforced polymer composites, the plastic piping industry in North America, and PET use in blow-molded rigid packaging. 

EVOH have superior gas barrier properties.80 89 They are often used as the internal layer in multilayer food packaging films, blow molded rigid containers, gasoline tanks for automobiles for a variety of purposes, etc. EVOH can be fabricated by the usual melt processing methods. The barrier properties of films decrease in the presence of moisture, so multilayer with protective polypropylene (especially biaxially oriented material), low-density polyethylene, nylons, or other moisture barrier films provides films or products that are useful even with liquids. The... 

Copolymers with 3-hydroxyvalerate (HV) with lower crystallinity and melting temperature as well as higher impact strength levels 5 % HV for relatively rigid injection-molded parts, 10 % HV for injection molding, extrusion, injection-blow molding of packaging material, 20 % HV for veterinary/medical applications with controlled active substance release. 

EVOH can be extruded in films, blow molded, or injection molded. It can also be processed by coextrusion or lamination, in combination with PE, PP, PET, nylons, and other resins. Applications in packaging include flexible structures and rigid containers, as shown in Table 4.12. Typical applications are ketchup and barbecue sauce bottles jelly, preserves, vegetable juice, and mayonnaise containers and meat packages. Nonfood applications include packaging of solvents and chemicals. 

The additives in PVC bottles for cooking oil and other food products must have FDA clearance. For flexible packaging materials, the most common stabilizers are mixed metals such as barium-zinc and calcium-zinc, which replaced the older cadmium-zinc formulations. For rigid blow molded containers and calendered sheets, or-... 

Barex resin extruded sheet and/or calendered sheet (153) can be easily ther-moformed into lightweight, rigid containers (152,154). Packages can be printed, laminated, or metallized. Recent developments in extrusion and injection blow molding (152,155), laminated film structures (152,156), and coextrusion (153,157) have led to packaging uses for a variety of products. Barex resins are especially well-suited for bottle production. These acrylonitrile copolsmiers also provide a... 

On the basis of volume, by far the majority of PVC is extruded. Rigid applications include pressure and drain/waste/vent pipe, siding, window profile, fence deck, and rail. Packaging applications include bottles (by extrusion blow molding) and rigid sheet. Rexible applications include medical tubing, hose, wire insulation (by extrusion coating), and cove base. 

HDPE accounts for about 42 percent of the domestic polyethylene market. It is harder, more rigid, and less waxy in appearance than HP-LDPE. Its higher density gives it better gas barrier properties. Because it softens above 100°C, containers made with HDPE can be sterilized, but those made with LDPE cannot. It is extruded into pipe, trash bags, food packaging, multiwalled sack liners, wire and cable coverings, and thick industrial film. A large application is for blow-molded containers and housewares. 

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