Biodegradable products.

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Just caught news of a significant step towards reducing the reliance we have on petroleum based plastic products. Pepsi-Co will soon be using a 100% plant based biodegradable bottle.

http://www.pepsico.com/PressRelease/Pep ... 52011.html
(more details in the link)

Range of products used by Pepsi-co (Liptons, Ocean Spray and more)
http://www.pepsico.com/Brands/Pepsi_Cola-Brands.html

Ok, so this is one single corporation (only one as far as i am aware) making a significant step towards reducing waste. I hope that this gives the intensive for other companies to make the same move within the next couple years.

We also have this Ted talk about a mushroom based packaging which would be (to the best of my knowledage) a flexible plastic to replace Styrofoam and the sort of plastics you'd find in a box of chocolates for two examples.
http://www.ted.com/talks/eben_bayer_are ... astic.html

It is a big problem that materials say like tetra pack styles of plastic which are commonly used are non-recyclable and that companies line cardboard cartons with metal, making it non recyclable.

Well I am quite sure all plastics could soon be non petrol based and that those types of designs could easily be adapted for use in many non recyclable products.

This trend in sustainable produce could hopefully influence manufacturing designs of other things like electronics too for example.

How long to people reckon until we see a huge difference in the way resources are used?

What other biodegradable materials do we have which could be considered sustainable?

Quite interesting, I'm fairly curious as to how they make PETE from organic materials. I've forwarded the article to my advising professor, he may know a bit more about it than I do. He's one of the biggest polymer experts in the Pacific Northwest, frequently consults for companies like Nike and HP (and I have the current honor of managing his research lab). Though Pepsi's claim to be the first to make a completely bio-based bottle is entirely untrue, that goes to Coca Cola for their polylactic acid (PLA) bottles. Granted, that never went very far, given the glass transition phase of PLA is around 50-60 celsius. I saw a cup made from it when out of town, grabbed it to take back to my lab to test, and the damn thing melted because I put it next to the heating vent in my car. Now imagine someone leaving a PLA bottle of pop in their car on a hot summer day....




The mushroom stuff is actually NOT a plastic. It may be a polymer, but it's most definitely what's known as a thermoset. Plastic is actually the short version of thermoplastic, which means you are capable of heating it and reforming it after it's been cooled, so it will have a glass transition phase (amorphous and semicrystalline plastics) and possibly a melting point (semicrystalline plastics). Thermosets mean once it's set, you can only break it down by destroying the chemical bonds in the polymer chains. I actually find his referral to it being "like plastics" somewhat annoying (though note how he never refers to it as anything other than a polymer), just because you can form it in a mold. That's like saying cement's like a plastic because of the ability to pour it into a mold. The big difference being you don't have to put a plastic into a mold as its chemical structure is being formed. Typically in industry a plastic's produced in small pellets called nerdles, which are shipped in large quantities to companies and fed into extruders hooked to injection molds. Very fast paced with minimal room needed. The fungi process requires a huge amount of room for a very small amount of product made in comparison. I would like to see this expanded further (and in a few decades we really won't have any other choice), but right now it is, unfortunately, ridiculously inefficient (we're talking five days to produce what can be made from plastic in a matter of seconds) and will really only be good for packaging (it is very much not flexible in any way).



It would be nice, but unfortunately we only have a few biodegradable, plant-based plastics available, and the only one that's useful outside of niche applications is PLA (which I've been doing random tests on for the past few years). Just because we have a biodegradable plastic doesn't mean it can automatically replace one of the Big Six + One plastics (1 - PETE, 2 - HDPE, 3 - PVC, 4 - LDPE, 5 - PP, 6 - PS, and + One being any of the other plastics, typically PC and more recently PLA, labeled as "7" on packaging). The reason a plastic is one of the Big Six is because A. they're cheap, and B. they can be used for a wide range of things because of their useful mechanical/physical properties.

There's also new methods coming out for recycling things though previously thought to be completely unable to recycle. Expanded polystyrene (EPS for short, Styrofoam is just the Dow trademark name) is actually recyclable, it's just a waste of energy to transport it to recycling facilities given how small its density is. Fill a truck with it and you have maybe 50lbs. They've developed a truck in Tokyo that travels around town with a tank partially filled with d-Limonene, a safe solvent made from citrus peels, which dissolves the EPS into a slurry for efficient transport. You can pick up quite a lot of EPS, then take it back to a production facility where the d-Limonene and polystyrene are separated with something around 95% recovery of the d-Limonene, and the reformed polystyrene has no loss in mechanical properties. Another project that we're working in on my lab is developing methods for third-world countries to use the EPS littering the land to create insulation for their homes.

On somewhat of the same note, it's kind of sad that right now it's actually BETTER to throw away your plastic right now, instead of recycling (especially if you're in the US). The main reason is because currently maybe 5% of the plastic you send to be recycled actually gets recycled (mostly PETE bottles and large HDPE items like milk jugs). The rest gets sent to either landfills or over to China to be used as a cheap fuel (wonderful). By only recycling PETE bottles and large HDPE items, you pretty much help turn landfills into gold mines for future generations (especially when oil supplies dwindle).

Anyways, I could ramble on for hours (especially given next term marks my 6th time being the Graduate TA for OSU's polymers class), but I'll leave it at that for now. There are a lot of cool things being developed out there, like the packing peanuts made from starch that are edible (we have a box in my lab, they taste like Cheetos without the cheese), but as my professor has said, we're going to have to start inventing a lot of new chemistry in the next decade or we're screwed.

Thanks for the reply! You have lots of interesting things to say.

I meant to say "plastic" in brackets when I mentioned the fungi mould thing. I never realised how inefficient it is to create though. That really really really sucks.

If you come up with more info about the bottle Pepsi-co are using write back about it. You'd understand more about the sustainability of the materials used, energy used in production, properties of the material itself etc etc. Would be interesting to find out how big an impact this sort of thing could make.

Oh goody! Now we can have soda bottle that leak before we pour anything out of them.

ruveyn

Biodegradable doesn't mean it's going to dissolve the moment you put anything in it. PLA in particular requires fairly hot conditions when you compost it to actually break down. It's to the point that places like Whole Foods won't accept it for composting because their method doesn't get hot enough.

One of the experiments I did on a PLA cup was to see how long it would take to break it down in Coca Cola, frequently washing out the cup of bacterial/fungal growth and replacing the soda in it. I gave up on it after it was over a year when the cup got damaged from something else, and even then it showed no signs of pitting, deformation, or any other deterioration caused by the Coke. I'd restart the experiment with chopped up pieces (and probably throw in some strips of that PLA Sunchips bag that was insanely loud), but I'm graduating at the end of next term and wouldn't be around to see the results (though I may end up doing it on my own). It also doesn't help that my fellow grad students "borrowed" my supply of Coke and I'm too cheap to buy another flat of cans from CostCo.


A company you should check out, PatrickNeville, is Agilyx. It's a company that's located between Salem and Portland that has developed a method of taking in a supply of plastics that would otherwise be sent to the landfill, and reconverting it to oil. The key thing here is that the plastic doesn't need to be sorted (the major pitfall of recycling, since very few people can tell the Big Six plastics apart just by looking at them), they can be thrown in together to produce the oil (which is very much like crude oil). I got a chance to visit their facilities a little over a year ago (back when they were called Plas2Fuel), and it's pretty neat what they've done. What's particularly nice is they have a completely closed system energy supply. The process creates several "natural" gasses along with the crude that can be fed back in to be burned as fuel for running the process, and there's always an excess that's stored and sold if they get too much. Sure, it's not biodegradable plastic or too terribly green, but it's another energy supply that doesn't give off toxic fumes like burning the plastic straight up would do and it keeps the plastic from ending up in landfills/the Pacific Gyre.

Awesome going to look them up mate.

The incomparability of plastics as you mentioned is a massive problem. Probably better in a lot of cases just to turn it back into a petrol like chemical.

Cool thread. Good news. Like it.