Containers, blow molding

Good methanol/gasoline fuel permeation resistance together with clearly defined MPAPVA and MPA laminar structures were found in containers blow-molded from PE/PMPAPVA and PE/MPA blends, respectively, with an optimum CP of about 20 wt% [302],... 

Permeation Rates in "CommerciaT Containers. Hie properties mentioned above were obtained in containers blow molded under experimental conditions. Similar performance has been demonstrated on a routine commercial basis. Table II describes the permeabilities in these containers. Hie results are comparable to that of containers made under laboratory conditions. 

Packaging is by far the largest outlet bottle caps, small jars and other injection-molded containers, blow-molded containers, toughened polystyrene liners (vacuum formed) for boxed goods, and oriented polystyrene film for foodstuffs are some of its uses. 

Whenever hollow objects are desired, like bottles and containers, blow molding (a modification of injection molding) is used. In this process, an extmder... 

Lodge, C., Troubleshooting Problems in Container Blow Molding, PW Directory, pp. 405-408, 1988. 

Glass Polyvinyl chloride Styrene-ethylene/butylene-styrene block copolymer containers, beverages Resorcinol di (P-hydroxyethyl) ether containers, blow-molded Phenoxy resin containment, acids Stainless steel containment, gases Stainless steel... 

Polyamide-polyolefin blends Moldings with improved modulus and heat distortion Multilayer containers Blow molding containers Polyolefin composites Thermoplastic elastomers Crosslinked, molded sheets... 

In container blow molds used in extrusion, there will be a hardened steel insert with a land of 0.003/0.005 in., then a relief angle of 20 degree... 

A. J. Woytek and. E. Gentilecore, "A New Blow Mol ding Process to Reduce Solvent Permeation of Polyolefin Containers," paper no. 13 presented at ddpances in Blow Molding Conference Rubber and Plastics Institute, London, Dec. 6,1977. 

Blow-molded products represent the biggest use of HDPE resins, at around 40%. Packaging appHcations account for by far the greatest share of this market. These include such products as botties (especially for milk, juice, and soap), housewares, toys, pails, dmms, and tanks. Expected aimual average growth rates for these appHcations are about 5—6%. Injection-molding products are the second largest appHcation, with approximately 20% of the HDPE market. These products include housewares, toys, food containers, pails, crates, and cases. 

Soft-drink bottles made from poly(ethylene terephthalate) (PET) are usuady made by stretch-blow mol ding in a two-step process. Eirst, a test-tube-shaped preform is molded, which is then reheated to just above its glass-transition temperature, stretched, and blown. Stretching the PET produces biaxial orientation, which improves transparency, strength, and toughness of the botde (54,56). A one-step process is used for many custom containers that are injection stretch-blow molded. 

PEN film for audio- and videotape and various electronic appHcations and blow molded PEN containers for hot-fill appHcations are already being marketed in Japan. NDA is unlikely to ever become as inexpensive as terephthaUc acid but novel NDA-based polyesters will become available if a market need exists. One example could be the experimental polyester PBN (Celanese Corp.) this is the NDA analogue of PBT, poly(l,4-butylene naphthalene-2,6-dicarboxylate) [28779-82-0]. It has a high rate of crystallization, faster even than that of PBT, and its combination of physical properties is weU-suited for injection molding. 

Hot-Fill Applications. A growing market for blow-molded containers is the so-called hot-fill market. This covers such items as tomato ketchup, pasteurized fmit juices, and salad dressings that are packaged while sti11 hot. The PET blow-molded bottie suffers from its relatively low T (70°C) which results in severe bottie distortion if the temperature of the contents approaches T (the maximum fill temperature is 60 65 C). A brief heat... 

Styrene-based plastics are used somewhat in blow mol ding but not as much as linear polyethylene and PVC. HIPS and ABS are used in specialty botdes, containers, and furniture parts. ABS is also used as one of the impact modifiers for PVC. Clear, tough bottles with good barrier properties are blow-molded from these formulations. 

PS or copolymers are used extensively in injection blow mol ding. Tough and cra2e-resistant PS containers have been made by multiaxiaHy oriented injection-molded parisons (238). This process permits the design of blow-molded objects with a high degree of controlled orientation, independent of blow ratio or shape. 

There are also bellows-style collapsible plastic containers such as blow molded bottles (jars) that are foldable. As shown in Figs. 3-16 and 3-17, the technology of foldable... 

Fig. 3-37 Example of an extrusion blow molded container with a living hinge.

Thin wall plastics are used to hot fill (injection and blow molded bottles, thermoformed containers, etc.) without sagging during filling and maintaining mechanical properties such as impact strength and stiffness in temperatures from at least —40°F to 250°F (—40°C to 120°C). Plastic used includes special grades of PEN, PET, PP, PS, and PVC. 

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