Plastics crash applications

In many applications, we exert forces on polymer products for extended periods of time. In such cases it is important that they do not deform beyond acceptable limits. We address this concern through creep testing, which may take days, weeks, or even months to perform. We can also change the rate at which we perform certain tests. Thus we might test the polymer resin to be used in a crash helmet at high speed to mimic an impact. In contrast, the film used in a plastic bag would be better tested at slower speeds, which are more representative of what it would experience during use. 

Shutdown of Oxochem s 2-ethylhexanol unit in 1978 eliminated 300 million pounds of capacity overnight. As a result, DOP users began a crash reformulation effort on alternative plasticizers. Linear alcohol and Cg and Ciq branched chain alcohol based phthalates as well as butyl benzyl phthalate, for example, were found to be wholly or partially substitutable plasticizers in many DOP applications. New 2-ethylhexanol capacity available starting in 1981 is expected... 

When plastics are foamed to low densities, containing more air than polymer, they acquire unique new properties and applications. Major uses are in crash padding and thermal insulation. Closed-cell foams are outstanding for flotation, rigidity, and insulation while open-cell foams are outstanding for softness, resilience, and comfort. 

North Carolina reports that recycled plastic guardrail blockouts actually work much better than wood and can often be reused after a crash. One of the applications is that of recycled plastic marine pilings. The plastic pilings eliminate the concern of wood-treated post releasing chemicals to the water body, and are not susceptible to the marine-borer worm... 

Yetham, L. A., Godfreg, P. M., Chinn, P. B. Materials for Motorcycle Crash Helmets a Finite Element Parametric Study. Plastics. Rubber and Composite Processing and Applications 1994 22 215-21. 

There is a multitude of polymers with widely differing properties, making them suitable for different applications like rubber tyres, crash helmets, food packagings, or plastic bags. This multitude is due to the fact that polymers consist of organic chain molecules whose structure can be controlled within wide margins (see also chapter 1). 

Material data determination for crash simulation is demanding due to the complex testing described above and the need for true stress/strain-data during plastic deformation with inclusion of the strain-rate dependency. Additionally the determination of loads and deformations that lead to failure is challenging. It bases on the application of optical measurement systems or the use of reverse engineering processes that allow the data determination by optimizing a material data card until the... 

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