Thermoplastic bottles

Thermoplastic bottles and other containers are growing fast by replacing glass principally but also metals in the packaging of food, beverage, household and industrial chemicals, oils, drugs, cosmetics, toiletries... 

STEP r. First you will need some plastics strips 3" to 4" long and 1/4" to 3/8" wide to feed the machine. The strips can be cut from a plastic milk bottle, oil can, soda bottle or other thermoplastic bottle or item. All plastic must be rinsed off and dried before putting it in the machine. No residue of any kind should be on the plastic when it is placed in the machine. Also remove any paper labels that may be on the plastic. For obvious reasons do not use bottles, containers or plastic items that have contained chemicals, insecticides or other harmfiil agents in your projects. 

Recycling of HDPE. Polyolefins, including HDPE, are the second most widely recycled thermoplastic materials after PET (110). A significant fraction of articles made from HDPE (mostly bottles, containers, and film) are collected from consumers, sorted, cleaned, and reprocessed (110—113). Processing of post-consumer HDPE includes the same operations as those used for virgin resins blow mol ding, injection molding, and extmsion. 

The principles of thermoplastic melt processing can perhaps best be illustrated by reference to Figure 8.1 illustrating extrusion, injection moulding, bottle blowing and calendering operations. In order to realise the full potential of the process it is necessary to consider the following factors ... 

With the expiry of the basic ICI patents on poly(ethylene terephthalate) there was considerable development in terephthalate polymers in the early 1970s. More than a dozen companies introduced poly(butylene terephthalate) as an engineering plastics material whilst a polyether-ester thermoplastic rubber was introduced by Du Pont as Hytrel. Polyfethylene terephthalate) was also the basis of the glass-filled engineering polymer (Rynite) introduced by Du Pont in the late 1970s. Towards the end of the 1970s poly(ethylene terephthalate) was used for the manufacture of biaxially oriented bottles for beer, colas and other carbonated drinks, and this application has since become of major importance. Similar processes are now used for making wide-neck Jars. 

Polyethylene is an inexpensive thermoplastic that can be molded into almost any shape, extruded into fiber or filament, and blown or precipitated into film or foil. Polyethylene products include packaging (largest market), bottles, irrigation pipes, film, sheets, and insulation materials. 

Polyvinyl chloride (PVC) is one of the most widely used thermoplastics. It can be extruded into sheets and film and blow molded into bottles. It is used in many common items such as garden hoses, shower curtains, irrigation pipes, and paint formulations. 

Can handle most thermoplastics. A big application area is bottles. Flat, concave or cylindrical surfaces. 

Fibers, engineering thermoplastic resins, bottle and container resins, films... 

Both thermosets and thermoplastics are used as food-contact materials, though thermoplastics predominate in this appfication. Examples of the former are phenol- and urea-formaldehyde, while probably the best known example of the latter is low-density poly(ethylene). Other linear polymers are used include high-density poly(ethylene), poly(propylene), and PVC, all of which find quite extensive use. Polymers for food packaging may be in the form of films and other flexible items, or in the form of rigid containers, such as clear drinks bottles or opaque cartons for dairy products. 

Polyesters, which are a class of engineering thermoplastics, are found in a wide variety of applications including carbonated drink bottles, fibers for synthetic fabrics, thin films for photographic films and food packaging, injection molded automotive parts, and housings for small appliances. In this chapter, we svill explore the synthesis of this class of polymers. We will also look at the typical properties and end uses for the most common of these resins, polyethylene terephthalate and polybutylene terephthalate, which are commonly known as PET and PBT, respectively. 

Thermoplastic molding applications for VDC copolymers, 25 726-727 Thermoplastic olefin polymer of amorphous structure (TOPAS), 16 113 Thermoplastic polyester bottles, recycling, 20 54-56... 

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

Aromatic carboxylic dianhydride chain extenders (e.g. PMDA) are a low-cost way of converting recycled PET flakes into high-IV crystalline pellets that can be used in high-value applications (e.g. bottles, strapping, foam, engineering alloys/compounds, etc.) (see Figure 14.2). PMDA is an effective chain extension additive for thermoplastic polyesters such as PET and PBT. It is suitable for the following applications ... 

PET is by far the largest-volume thermoplastic polyester in production today. It was first synthesized by J. R. Winfield in the UK in the 1940s and its first commercial application was as a textile fiber. PET was also produced as a film for packaging and blow molded into bottles for beverages long before it had any... 

The workhorse polyester is polyethylene terephthalate) (PET) which is used for packaging, stretch-blown bottles and for the production of fibre for textile products. The mechanism, catalysis and kinetics of PET polymerization are described in Chapter 2. Newer polymerization techniques involving the ring-opening of cyclic polyester oligomers is providing another route to the production of commercial thermoplastic polyesters (see Chapter 3). 

Figure 2.22 shows the supremacy of polyethylene and thermoplastic polyester (PET) in the European bottle and other blow-moulded container market. 

When the polypropylene (PP) technology finally ripened in the late 1950s, the chemicaL.industry was quick to harvest numerous applications. The primary attractions of this thermoplastic were the ease of molding or extruding it and its ability to hold color. Some of the familiar applications are automotive parts, luggage, pipe, bottles, fiber (particularly carpet face fiber and rope), housewares, and toys. 

For higher throughput applications, injection-molded plastic microtiter plates have served as the formats of choice for automated assay development. Thermoplastics such as polystyrene, polycarbonate, and polypropylene are used for a variety of purposes including storage and assay plates, lids, pipette tips, and Eppendorf PCR tubes. Polystyrene plates are used for cell culture and ELISAs. Polycarbonate reagent bottles are popular, while polypropylene storage plates and PCR tubes are standards. 

Total recycled thermoplastic resin production almost tripled between 1990 and 1995 and is well over 1 billion lb per year. The percentage breakdown of the amount for recycling is the following HDPE (especially bottles), 35% PET (soft drink bottles), 34% PP (auto battery cases), 14% LDPE (film), 9% PS (packaging), 3% PVC, 0.5% other, 4%. 

Molding employs a mobile prepolymer that may be thermoset or using a thermoplastic polymer. The polymer can be injection-molded (often for solid objects), blow-molded (for hollow objects such as bottles), rotation-molded, compression-molded, transfer-molded, or thermoformed. Casting is closely related to molding, except that the pressure is typically not used. 

HIPS is a thermoplastic that is widely used in packaging, toys, bottles, housewares, electronic appliances, and light-duty industrial components, because of its good rigidity and ease of coloring and processing. Flame retardant HIPS polymers find application in housings for business machines. Here we present recent issues and examples on applications of HIPS. 

Noncrystalline aromatic polycarbonates (qv) and polyesters (polyarylates) and alloys of polycarbonate with other thermoplastics are considered elsewhere, as are aliphatic polyesters derived from natural or biological sources such as poly(3-hydroxybutyrate), poly (glyc olide), or poly (lac tide) these, too, are separately covered (see Polymers, environmentally degradable Sutures). Thermoplastic elastomers derived from poly(ester—ether) block copolymers such as PBT/PTMEG-T [82662-36-0] and known by commercial names such as Hytrel and Riteflex are included here in the section on p oly (butylene terephthalate). Specific polymers are dealt with largely in order of volume, which puts PET first by virtue of its enormous market volume in bottle resin. 

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