Blow injection-stretch

Injection stretch-blow molding may be performed on a single one-stage machine in sequence or on two independent sequential two-stage machines. PET carbonated beverage botties are usually produced by injection stretch blow molding. 

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. 

Fig. 4.25 Extrusion stretch blow moulding Injection Stretch Blow Moulding...

Injection-production wells, in soil and ground water treatment, 25 835 Injection stretch blow molding, of food packaging, 18 50-51 Injection wells, 18 613... 

Injection stretch blow moulding in which all the operations are performed on the same line. The preform is stretched with a stretch rod . Stretching improves the mechanical performances and allows the production of thinner walled bottles. 

Single-screw extmsion in general is the most important conversion process for biodegradable plastics. Only injection-molded and injection-stretch blow molded rigid containers like closures and bottles are not produced by a continuous extmsion process. 

The multilayer film is formed by injection molding, co-injection blow molding, co-injection stretch-blow molding or co-extrusion blow molding techniques. 

A process that greatly improves blow molded product properties is that of injection stretch blow molding, which introduces biaxial orientation in crystallizable polymers. There are two variants of this process involving the molding of a preform as the first step. The thermomechanical paths of the two process variants are shown in Fig. 14.19. In the... 

Fig. 14.19 Thermomechanical histories of the two variants of the injection stretch blow molding process (a) the two-step, and (b) the less common one-step.

Fig. 14.20 Schematic representation of the injection stretch blow-molding process. Step (1) producing preforms may be carried out in different location from the stretch blow molding process. [Reprinted by permission from Schmidt et al., Experimental Study and Numerical Simulation of the Injection Stretch/Blow Molding Process, Polym. Eng. Sci., 38, 1399 (1998).]...

Development of markets for PLA injection stretch blow moulding applications. 

The main markets for PLA are thermoformed trays and containers for food packaging and food service applications. Other developing areas include films and labels, injection stretch blow moulded bottles and jars, specialty cards and fibres. 

The main types of NatureWorks PLA that are available for packaging applications include general purpose film grades, extrusion coating, extrusion and thermoforming grades and injection stretch blow moulding. 

PLA is available in grades suitable for manufacture of injection stretch blow moulded bottles. It is claimed these offer comparable organoleptic properties to glass and PET making it suitable for a variety of short shelf-life food and beverage bottling applications. 

Injection stretch blow moulding (ISBM) is used for the production of high quality and high clarity containers. PET is the most widely used polymer for injection stretch blow moulding of botdes. During the last two years, there has been a growing interest from brand owners and retailers in the use of PLA for manufacture of stretch blow moulded botdes for short shelf-life products such as mineral water and milk. 

Injection stretch blow moulded bottles and jars for short shelf-life applications that use cold-filling techniques such as still water, fresh juices, dairy beverages and edible oil. 

As PLA prices move closer to those of PET there may be a tendency for brand owners to switch from PET in favour of biodegradable polymers such as PLA for injection stretch blow moulded bottles, not only on cost grounds, but also because renewable packaging materials have marketing advantages for the consumer. 

Alpha Packaging manufactures botdes and jars made from polyethylene terephthalate (PET) and high-density polyethylene (HDPE) for the pharmaceutical, nutritional and personal care markets. Technologies used include injection blow moulding, injection stretch blow moulding, and extrusion blow moulding. Alpha manufactures stock and custom containers in a variety of styles and colours. 

Fig. 20.4 The injection stretch blow moulding process (ISBM).

Two basic methods are used in this process to deliver material to the processing units. These are extrusion and injection. In the next step, the preformed material is expanded to form parison. There are many commercial variations on this basic technique some of which include continuous-extrusion-blow-molding, coextrusion-and-sequential-blow-molding, and injection-stretch-blow-molding. Both extrusion and injection molding are the subjects of later discussions below, we will concentrate here on the parison formation, its processing, and the related effects. 

Although both processes can produce reasonably good quality large containers, injection stretch blow moulding is more widely used for pharmaceutical containers. The first stage of moulding is basically as injection blow moulding. In the second... 

Figure 12.13 Injection stretch blow molding, (a) injection molding of parison, (b) stretch blow molding of container (reprinted with permission from [1 ])...

Extrusion stretch blow molding begins with an extrusion blow molded preform injection stretch blow molding begins with an injection molded preform. Injection stretch blow molding is the method of choice for most PET bottles, including all soft drink bottles. It is also used for PEN bottles and some PP bottles. Extrusion stretch blow molding is used for some PVC bottles. 

ISBM injection stretch blow molding K Kelvin... 

In contrast, PEN meets the requirements, but more complex forming techniques are needed. PEN bottles cannot be produced by simple extrusion blow molding. PEN requires the use of the more complex two-step injection stretch blow molding process. In this process, a preform is first injection molded and then stretch blow molded to produce the final bottle. This is the same process used to produce bottles of the related polyester, PET. 

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