RamDragon (ramdragon) wrote,

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Corn Polymers

Yesterday, I think I said something about corn-based plastics not being recyclable. I've been berzerking Google ever since to discover the truth of the matter. I think I've penetrated the green cloud of confusion and mad an important re-discovery. At least, for me it was.

Bio-polymers can be made from many types of crops, including soy and corn. Corn polymers tend to be favored in the US because, well... we grow a lot of it. It's regional. So I discover all sorts of products made of bio-polymers. Cloths, straws, cell-phones, lap-tops, water bottles. Pretty much everything plastic can be made from corn polymers. Why would we want to use corn polymers?

Well, it's an annually renewable resource. No matter how much is used, we can grow the same amount next year. (I'll not go into farming ethics and the dangers of over-farming the land here.) The manufacturing process releases fewer pollutants than traditional plastic manufacturing. It seems that most people in the industry are of the opinion that bio-polymers can potentially be far cheaper to produce than petroleum plastic, and in fact it is currently only slightly more expensive.

Oh, and they can break entirely down in only a few months. Bio-degradable. But who wants a lap-top that will mulch itself in a few months? Well, the polymers don't just break down of their own accord. They need heat.

And that's the part that annoyed me when I discovered it. Also the enormous amount of fuel used in harvesting and transporting the corn and then turning it into ethanol before becoming bio-polymer. So, if you use a corn-polymer product, and then just chuck it... it will sit in the landfill forever. Just like petroleum polymer. See, you need to send it to a place that knows how to dispose of it, and the trash-truck won't do it.

Recycling? Heh. Turns out that heat activates the ability to bio-degrade. So, bio-polymers can't just be remelted and reformed. They need to be broken all the way down and fed back into the bioreactors that ferment the oils into polymers. It's cheaper to just grow more corn.

But, even if I think bio-polymers are a bad choice now, I do think that the technology has potential. I also think it'll be decades before bio-polymers can replace petroleum plastics for responsible recyclers. And I still think it's a waste of valuable farm-land that can be tasked to feeding the people around the world who are dying of hunger.
Tags: biopolymer, green, politics, recycling
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