Physical Product Designer Question:

Rather oddly, polymers are both solid and liquid at the same time. They behave unlike any other material. The career of a designer lasts hardly long enough to gain thorough understanding of the polymer nature, but in order to avoid the most obvious pit falls of plastic design it useful to have knowledge of the reasons and mechanisms behind them. Mechanical loads, environmental conditions and time - especially in combination - challenge every plastic product. If they have not been properly considered in design, the product is unlikely to last to the end of its expected lifetime .