Thursday, January 16, 2014

Recycling Plastics for the Do-It-Yourselfer

A few months ago, a Dutch designer Dave Hakkens got a favorable splash over his new equipment for recycling plastics. The equipment is based on what is commercially used in recycling and other polymer processes, but it is stripped down to be easier for people to make at home. Take a look at the video:Processing plastics (or reprocessing plastics in this case) at home has always been rather difficult just because of the temperatures that are needed and also the importance of reaching those temperatures quickly. High-density polyethylenes for instance, need to be heated to about 170 oC or more to really start flowing nicely. This is something that a home oven can hit, but as I just mentioned, it also needs to be applied to the plastic rather quickly. The longer plastics are exposed to high heat in an oxygen atmosphere, the more they will degrade. Degradation leads to a loss of mechanical properties at the plastic cools and also to color changes (usually a rather unlovely shade of yellow). That is why an extruder is used so much. The screw has a large surface area to spread out the polymer allowing for more effective heat transfer.

But outside of that, there is really nothing magical about processing polymers. That this person is able to strip back some of the mystery is helpful for people wishing to have a better understanding of what is involved as well as for those that want to get involved.

Previous Years

January 16, 2013: Does Going Public Kill Innovation?

January 16, 2012: Flying Cupcake Update

January 16, 2009: The Pitch Drop Experiment

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