High density polyethylene containers

High density polyethylene, shown in Fig. 18.2 a), consists primarily of linear hydrocarbon chains of the type shown in Fig. 18.1. We commonly abbreviate its name to HDPE. As with all other polymers, high density polyethylenes contain a distribution of molecular weights. The molecules have few, if any, branches. 

A series of triethylsilanol/methanol/water mixtures were prepared as shown in Table 1 and stored in clean high-density polyethylene containers at room temperature. They were monitored for changes in component concentration and it was determined that after 100 days they had reached equilibrium. 

Stabilities of lake and tap water samples for aluminium speciation were investigated (Fairman etal., 1994). Concentrations of 25-1000mgl 1 total aluminium in high-density polyethylene containers were stable for 30 days. Thereafter, increases in pH resulted in the precipitation of aluminium hydroxy species. 

Packaging and Storage Store liquid Grape Skin Extract with aseptic packaging or in high-density polyethylene containers at 4° to 14°. Store powdered Grape Skin Extract in fiber drums at room temperature. 

Select reagents having as low a lead content as practicable, and store all solutions in high-density polyethylene containers. Rinse all plastic and glassware thoroughly with warm, 1 2 nitric acid followed by water. 

Prednisolone phosphate eye drops are very photosensitive when packaged in clear colorless glass ampoules as well as in uncolored, high-density polyethylene containers. When exposed to UV and VIS radiation, the drug substance is completely decomposed within a few hours. However, packaging the prednisolone phosphate solution in brown glass vials, results in satisfactory UV-VIS photo protection (6) as shown in Figure 2. 

Figure 2 Photostability of prednisolone phosphate-eye drops (0.13% FNA, Formularium der Nederlandse Apothekers) stored in different types of containers in the Novasoltest light testing cabinet. ( ) brown glass containers, ( ) uncolored high-density polyethylene containers, (o) clear glass ampoules. Source Ref. 6.

In Delaware, this oil (4500 gal/yr) is recycled at the oil refinery at Delaware City 306 Liquid carbon dioxide is being used to take motor oil off of high-density polyethylene containers, so that both can be recycled.307 Safety-Kleen Corp. offers nationwide collection for used oil and antifreeze from cars and other sources.308 Mobile on-site services are also available for removing toxic compounds and acid degradation products from ethylene glycol antifreeze, with addition of new corrosion inhibitors, so that the antifreeze can be reused.309 Organoclays have been used to remove oils from water.310... 

HDPE exists as both a homopolymer and a copolymer with higher ethylene olefins. The latter offers properties which lie between low and high density, with typical densities of 0.945-0.950. Copolymers have found wide usage for extrusion blow, injection blow and injection moulding. They are, however, generally classified under HDPE. Virtually all high density polyethylenes contain an antioxidant. 

Adding or changing a child-resistant closure, changing from a metal to plastic screw cap, or changing from a plastic to metal screw cap Changing from one plastic container to another of the same type of plastic (e.g., high-density polyethylene container to another high-den-sity polyethylene container)... 

Figure 15.10 Weight loss due to fungal attack (C. trabeum) as a result of moisture sorption. Extruded composites of high density polyethylene containing 50% wood flour [50].

Some common products packaged in high-density polyethylene containers. 

Table 15 provides an ICHQID example of a bracketing design. This example is based on a product available in three strengths and three container sizes. In this example, it should be demonstrated that the 15 and 500 ml high-density polyethylene container sizes truly represent the extremes of such a design. 

Common name High density polyethylene containing glass fiber and carbon black ... 

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