Blow molded bottles

Polyesters exhibit excellent high temperature strength and electrical properties making them a good choice for many demanding applications. They also are physiologically inert allowing them to be used in food contact applications. The two common polyesters, polyethylene terephthalate and polybutylene terephthalate, are both used in injection molded products. Polyethylene terephthalate is often used in both extrusion and blow molded processes also. 

How do polyethylene terephthalate and polybutylene terephthalate differ from one another chemically How do these differences affect their properties  

Why is it so important to remove water from polyesters during the polymerization processing as well as during melt processing  

Why does the incorporation of ethylene glycol in polyethylene terephthalate reduce the crystallinity of the final polymer  

Polyethylene terephthalate is the dominant material for the manufacture of carbonated beverage bottles Why are the bottles clear despite the tendency for this polymer to form crystalline domains  

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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... 

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. 

A similar problem is presented by vehicle tires and certain blow molded bottles, which must be virtually impermeable to air and other gases. An example of the use of a very impermeable elastomers is butyl rubber. Because of its impermeability to gases, butyl rubber is used as a roof coating. With plastic bottles, different layers of both coinjected and coextruded plastics (Chapter 8) can be used to fabricate the bottle to make it impermeable to different vapors and gases depending on the barrier plastic included. 

Nylon barrier layers are used in packaging films and blow molded bottles. In these applications, their excellent resistance to oxygen permeation are valued when packaging greasy foods, such as potato crisps (chips), that rapidly turn stale when exposed to oxygen. 

PEN blow-molded bottles, 20 50-51 Pencil leads, kaolin application, 6 688t, 696 Pencils, graphite in, 12 795 PEN copolymer bottles, 20 52 Pendant cationic azo dye, 9 423 Pendant chain polymers, fullerene,... 

Thermoplastic polyesters, 20 31-95. See also Liquid-crystal polymers (LCPs) blow-molded bottles, 20 45-47 bottles for demanding contents, 20 52-53... 

A significant fraction, more than 25%, of the low-density polyethylene (LDPE) (Sec. 3-14a) produced by radical polymerization consists of various copolymers of ethylene. LDPE has come under increasing economic pressure in recent years because of a combination of factors [Doak, 1986]. High-density polyethylene (HDPE) has displaced LDPE in applications such as blow-molded bottles and thin films where the increased strength of HDPE is preferred over the clarity of LDPE. Linear low-density polyethylene (LLDPE) (Sec. 8-1 lc) competes effectively with LDPE in terms of both cost and properties. New producers of ethylene have entered the LDPE market because of a lack of alternatives for their feedstocks. Many LDPE producers use copolymerization as a strategy to obtain products more resistant to displacement by HDPE and LLDPE. 

Polypropylene blow-molded bottles are used to package a wide variety of products including foods, cleansers, shampoo, pharmaceuticals, and mouthwash. 

Blow-molded bottles, which exhibit excellent prodnet resistance, and good clarity, are also expected to become an important outlet for rigid PVC. 

The engineering applications of PET resins include blow-molded bottles, films, molding, and extrusion. Resins made for the latter two uses and related purposes are called molding resins in this article. The huge volumes of PET resin used for textile filaments and industrial fibers, eg, tire cord, are not included here. The PBT resins are mainly used for molding and related applications. 

Different processes take advantage in applying orientation to gain certain properties in certain products. Major product lines include stretched blow molded bottles/containers (Chapter 6), thermoformed oriented containers (used for such products as fruits, vegetables, and baked goods) (Chapter 7), tapes, etc. 

Figure 8.10 Schematic of injection blow mold with a solid handle (left) and simple handles (ring, strap, etc.) can be molded with blow molded bottles...

Cases III and IV are of direct interest to the packaging industry. Case IV, in fact, relates directly to monomer migration in blow-molded bottles. Daniels and Procter have treated simultaneous diffusion of VCM into the environment and into the package contents over a time scale sufficient to invalidate the assumption of independent diffusional processes at each of the bottle wall boimdaries. Over relatively short time periods, approximately half of the VCM originally sorbed in the bottle wall tends to diffuse into the environment and be swept away while the crther half (in the inside half of the wall) tends to diffuse into the package contents and increase its VCM content. Such a simultaneous process increases the VCM concentration at the... 

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