The Impending Polymer Post

In an earlier post, I started going off on a tangent and talking about my hobby of trying to determine which polymer something is made of. I deleted it from that post, because my goal in this blog is to be slightly entertaining and also to improve my writing skills . . . you can attest to how that goes. Anyway, here is that tangent:

It's actually not that hard to figure out which polymer you've got, and it's super easy on the 'recyclable' types, because you can check if you're right! There's a little recycle symbol on the bottom, and it'll have a number in the middle that will tell you exactly what you're working with. Sometimes it even has an abbreviation of the polymer name. After guessing a few times on those, you can get pretty good at it. As for the non-recyclable types, I pretty much just guess.

It also helps to know what a few polymers tend to look and feel like and what a few companies tend to use. For instance, Rubbermaid uses polyurethane and polyethylene. Plus you could probably make a good guess from this list of fairly common polymers that you've probably seen at some point: polyvinyl chloride (PVC), ABS, Lexan polycarbonate resin (the nalgene polymer--the bottle part, not the strap), acrylic, epoxy, polyester, nylon, as well as all the 'recyclable' polymers on the list--polypropylene, high density, low density, and regular polyethylene, polystyrene, and polyethylene terephthalate--check that one out. It's a weird name, but I bet you've used that today. Boy oh boy, that was fun, but I'll tell you the story of why it's the environmentalists' faults that we can't recycle Styrofoam in this country later--also probably why I use quotes when I say 'recyclable.'

Anyway, the reason I decided to write the polymer post is that I continued trying to fix my nalgene today. I had already cut the broken part off, and recut the strap further down to fit it on the notch. It was a pretty soft material, so this was not hard.
I decided to try to make it stronger, though I was pretty sure that was a lost cause. When you make metals stronger, you heat them up so the atoms align in their crystalline structure, and then you quench the metal so the atoms stay where they are when the metal comes back to room temperature. Polymers don't really work like this. They either can be made crystalline, or they can't, and the more complicated they are, the less chance you have of having a material that will crystallize. Anyway, I was fairly certain I was not going to get the polymer above the crystallization temperature or the melting temperature safely in my kitchen, and I was even more certain that this was not going to make it stronger in any way, so really I was just playing around. I stuck it in boiling water, and quenched it, and guess what? It didn't work! I boiled it again, and simply worked the plastic together so it might stay together more. I had stretched it out a bit when I forced in onto the little nubbin on the top of the cap. That seems to have actually helped with the strength some, because now it feels slightly stronger than before, but I really have no way of measuring that.I suppose it's always good to know that if you have something made of polymer, some types become workable around 100 C. They don't melt at 100 C, so you can't mend cracks or holes, but you can reshape them sometimes. A butane lighter can be hot enough to actually melt the polymer, but it would be difficult to use unless it was used on fibers (eg. nylon and polyester). Boiling , of course, is only useful if you ever run into a problem where you'd need to reshape something. If anything melts in your attic over the summer, chances are spectacular that it'll shape right up if you stick it in boiling water and reshape it.

That's my polymer post! Hope you enjoyed it!