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Being American culture is so dependent on mass infrastructure could a way to attack a non green lifestyle be devised by more clever material schemes?

 

Say some polymer was developed, that with minimal energy requirements could be molded to a variety of purposes, and even have greater recycling capability? Now this may sound a bit like plastic, but plastic is hardly green and in terms of simple waste which returns to the earth in a very negative way to the biosphere for instance is hardly a grand solution. I would think though that material science does not have to stop at plastic, which is what I would like to discuss.

 

Could green materials for any purpose such as packaging make it in the real world? What are some viable candidates?

 

I personally think hemp is a great plant for use in industrial processes on down to clothes. Hemp farming is also legal in some states, which shows promise for a potential market.

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The only real problem with plastics is that they're petroleum-based, and therefore not sustainable. Being that they're incredibly ubiquitous, we're necessarily going to see a major shift in materials in our daily lives. What I gather you're asking about is materials that can might make this shift painless, i.e. something as cheap and versatile as plastics but also sustainable, correct?

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Plastic is so very versatile, I doubt any single product could replace it. However, a multitude of products could certainly do so, albeit at a higher price.

 

Aluminum cans or glass would replace it for soft drink containers, for example.

 

However, I wouldn't want to replace plastics with a solution which is less green...

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If memory serves plastic breaks down to some very tiny scale, I think particulate over time in the oceans. I think this process can also serve to concentrate pollutions and it is also taken up by other organisms and works its way up. The amount of plastic such as waste by people that can come to mass in the oceans for example is disturbing to say the least. Also it is a product possible of the fossil fuel system that is the parent of so many problems.

 

Science still struggles to understand the impact of chlorine to be honest, so I do not see how good of thing making plastic so abundant with such behavior is beneficial to humanity, not at least while it is showing so much of a negative trend.

 

Making products that have less of an impact I think is more apt to help such a situation more then simply trying to curb behavior of say a populous constantly.

 

I do not see why simply on a chemical level a material cannot be devised for mass production that can be recycled easily and efficiently, but to be honest with what could be a gold mine for innovation these days you find a market that really has no steam. The hybrid car market is only going to succeed I think, that is the automobile industry, or world domination. Yet in that I find that one of the prime motivations or reasons its possible in simple economics when it comes down to it, so any breakout product would I think have to work economically, this is why I said hemp primarily.

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Not all plastics are petroleum products based. Plastics made from vegetable starch are commercially available. ( think also of cassein). These are readily and naturally biodegradable. They do have commercial (profit/convenience) disadvantages however. Two that spring to mind are:

 

1. They are not so easy to mould/extrude using mainstream "off the shelf" mass-production machinery compared to petroleum plastics for which the processes were designed.

 

2. Being naturally biodegradable, their shelf-life and therefeore commercial convenience is limited.

 

I think that as with so many "green" alternatives, a seismic shift in commercial and consumer thinking is required before such less convenient products become mainstream.

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There are good alternatives for many plastic products. But we should first of all realize that a lot of plastic is in fact no "product", but a packaging material.

 

For packaging, no high quality materials are needed. Paper or recyclable materials can be used. We can reduce the plastic consumption easily, especially packaging materials. If you look at an average pack of cookies, then often each cookie is packed separately. Then they're all neatly put in some kind of shape, for the purpose of keeping them in 1 piece while being moved (rough handling is now possible), and presentation. They are then wrapped into a colorful packing plastic, put together in a box, which is cealed in again more plastic.

And it's not uncommon that even more layers are added to the packaging. And often these cookies have traveled further than I have in my lifetime.

 

Also, I cannot remember when was the last time I have had anything electric repaired. We don't even seem to consider the option: throw it away and buy something new.

 

In fact, electric appliances are constructed with special screws with the sole purpose that you cannot open it yourself. You're not supposed to be able to re-connect some loose wiring. (Imagine the claims if you'd electrocute yourself).... that all leads to more and more waste, and in the same time it serves the economy well.

 

There is also still a habit of getting a plastic bag with everything you buy. It's a worldwide habit not to take your own (empty) bag with you when you go shopping.

 

My point (in short): let's focus on reducing plastic consumption as well as on replacing it by sustainable materials.

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I wonder to what degree the problems we see from plastics are caused by lack of recycling. If we recycled every last bit of it, it wouldn't be a problem at all that it takes forever to degrade, right? Quite the contrary! Even plastic packing, about which I generally agree with CaptainPanic, wouldn't really be an issue, I don't think.

 

On the other hand, there already is plastic recycling infrastructure in place in most places, and huge amounts of it are still just thrown away. So I wonder how realistic near-100% recycling actually is. Furthermore, I can't seem to find a straight answer on the economic efficiency of it.

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I don't think that 100% recycling is feasible: there are too many types of plastic to simply put them together, heat a little, melt the plastics, and re-shape it. The different types of plastics don't blend (mix) very well. The simple recycling is only possible if we'd collect the plastics separately, but there are just too many types.

 

The recycled plastics are generally a bit lower quality products: garbage bags or injection molded garden furniture. Not the high quality iPods or so.

 

The more rigorous recycling (gasify, fischer tropsch, crack, polymerize) is less efficient (my estimate would be that the yield will not be above 70%... although I haven't done any calculations on this). Losses come from the partial oxidation that you need to do in the gasification, and from the chars (which contain carbon) that are formed in the gasifier and cracker.

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Well if the plastic continues to flow into the oceans it will become more and more of an issue, one I don’t think anyone can afford to clean up. IF what exists now can be put into a timeframe of plastics birth to mass consumption I would think fifty more years of such would only increase the problems magnitude and duration.

 

Plus all of the plastic is a waste in terms of energy and resources put into processing it in the first place. American economical system is capitalist, so a company has to take a greater then usual risk floating something green, typically because it has higher costs associated to produce and again you have to count on a consumer base even being there.

 

Hybrid car technology I think represented the winning formula. Change as needed for various reasons has provided an economic desire to obtain a car for instance that gets better miles per gallon, so with that again I think a potential green product surely has to work economically, if it could do that I would wager more money would be risked producing such, again counting on a customer base.

 

Hydrogen economy cant exist because the technology is simply out of reach, its out of reach because big money will not fuel it as is. I do not think the big boom in hydrogen is going to occur with a home inventor, this is a much larger creature, as is a replacement to plastic for mass consumption, I also do not see much money going this way.

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I fact, I think we should be heading for those waste dumps with boats, and clean those seas. If it's concentrated, then it can be harvested. (I know concentrated in this case means it's about the same density as the plankton, but that is exactly the reason we should get out there... I consider that hugely concentrated...).

 

We're mining tar sands in Canada too, aren't we? (I speak of "we" since we all burn something fossil).

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Who's going to take the bill?

 

I'd love to see it cleaned up, but who is going to pay? All the more reason for the USA, EU, Asean etc to gradually unite and become a WU (World Union). Then with 'world peace' sorted and less need for mega-military, we can pay for this, feed the world, run on renewables, kill pests (Cane-Toad, Wild pigs etc in Australia for example), accelerate the development of open source software (OK, that' one's a pet hobby horse), and eventually terra-form Mars.

 

But right now we can't even clean up our oceans.

 

I think it would depend on how it attacks any giving organism. I think if you look at it from say an energy web type of view you get transmission of pollution, so you end up consuming more toxins then normal, this also can have its own impact depending on specie, such as with a larger animal to a smaller one, or how many offspring they make.

 

If it attacks areas like coastal regions for instance, I think you deal again with a symptom all of its own. Basically I think it integrates into most every level of selection to some extent in regards to the biosphere.

 

Plus I would wonder how it would then work into geology cycles or phenomena. Such as what will increasing concentration of various polymers do to say transfer of salt in the ocean?

 

I think you begin to deal with larger but similar problems, such as with concentration of CO2 you have a warming problem, what will concentrations of plastic increasing yield, or how does that work? So maybe many global environmental problems have similar traits.

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True, cellulosic plastics ar used currently from toys to food pacaking. For food packaging, there are warnings about not using it in the microwave since the melting temp is much lower than petroleum based.

 

Regrind is difficult to work with in molding a new product. It is currently used in some applications but I don't think I would want IV tubing made from regrind as it is more brittle and less reliable.

 

Heck, I take canvas bags when I shop and hope that I am helping. However, I think that some plastics are necessary in certain instances to prevent contamination. That being said, so many people don't recycle as much as they could be.

 

I may be biased in this since my husband has worked in medical plastics for 20 years ;)

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Who's going to take the bill?

 

I'm so naive, but I always hope governments will take responsibility. In the Netherlands we have several taxes that are "environmental" (there's additional tax on gas/diesel and on electricity too I think - there is tax for disposal of all kinds of machines you use in the household - there's of course road tax and general waste tax and water tax. And I must have forgotten a few more).

 

Unfortunately, I don't really see any of that money going back to the environment. :-(

 

(Brainstorming a solution to it:)

How difficult can it be to make some trawlers with a fine maze, and filter out everything (eeh, yes, that probably includes our marine friends too).

 

From the (previously linked) wikipedia of the Great Pacific Garbage Patch:

"The study found concentrations of plastics of 3.34 pieces with a mean mass of 5.1 milligrams per square meter."

That means 17.034 mg/square meter (not per m3??).

 

A 5.1 mg piece of plastic, if spherical, has a volume of 5.1 ul (microliter), or 5.1E-9 m3. Its diameter is 1.1 mm... which means to filter out most of that crap, we'd need a mesh of something like 0.5 mm (that's small!).

 

Tomorrow's exercise: calculate how much power is needed to pull along a large mesh of 0.5 mm to filter stuff, and if the plastic (when combusted) gives enough energy to power this trawler :D

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From the (previously linked) wikipedia of the Great Pacific Garbage Patch:

"The study found concentrations of plastics of 3.34 pieces with a mean mass of 5.1 milligrams per square meter."

That means 17.034 mg/square meter (not per m3??).

 

A 5.1 mg piece of plastic, if spherical, has a volume of 5.1 ul (microliter), or 5.1E-9 m3. Its diameter is 1.1 mm... which means to filter out most of that crap, we'd need a mesh of something like 0.5 mm (that's small!).

 

Tomorrow's exercise: calculate how much power is needed to pull along a large mesh of 0.5 mm to filter stuff, and if the plastic (when combusted) gives enough energy to power this trawler :D

 

It is called an average, there aren't actually millions of little balls floating around in the sea, there is just a piece of rubbish in 1/1000 of the square meters, or some number similar.

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It is called an average, there aren't actually millions of little balls floating around in the sea, there is just a piece of rubbish in 1/1000 of the square meters, or some number similar.

 

I know that it's an average, and that there will be lots of particles that are smaller (and a few that are larger). That is also why I proposed a mesh of a bit less than half the size (which, I admit, was an arbitrary choice because I don't know the type of size distribution that would apply to this set of particles). the goal should be to filter out, say, 90% of the plastic. You cannot expect to clean it up completely. We'll have to wait until plastic-eating bacteria evolve for that to happen (I wonder which biologist will respond to this remark).

 

I'm just trying to be positive, but it seems I still didn't feel like doing some simple calculations :D

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  • 2 years later...
Guest sofiazara

I can remember growing up in the sixties in a world which was still relatively "plastic free". Do you remember when foods were actually packaged in glass, paper and cardboard? Do you also remember when the paper and cardboard was thicker back then? I can still remember as a boy looking at one of those "foam" cups made from polystyrene and crumbling it, it was in the late sixties, wondering what the heck it was made of! The one litre soda bottle was made from glass a long time ago, for which I got twenty cents for when I collected them from the side of the road and brought them into the corner store.oshawa criminal lawyer

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Interesting, people. well, maybe I can add something to the speculation on how much plastic waste if floating in that Great Pacific Garbage Patch: A researcher at the Univ of Plymouth (Englland, of course), actually went out there a few yrs ago. Calculated with his crew, there is about 3 million tons of plastic floating there. And that does NOT include the submerged/suspended in layered water columns all the other plastic. Yup, it is a shame. They traced it to LA area streams/rivers/etc that have the plastic blown there from atop of land fills/dumps in CA. Dont remember exactly if that book (which detailed this research) attributed blame to other countries or not.

 

I heard Europe just last month banned plastic bags. As far as government, I dunno about that. Seems like govt is expected to solve our problems. Danish and German and Spanish govmt got nowhere with their green agenda- windmills/solar/etc . Denmark ended up importing electricity from Norway, companies are leaving Spain for the US, Italy is planning to build now Nuclear plants (at least, before the Japan thing) Taxes are sooo high.

 

I'll be the first one to say my life will,be a little tougher without some plastics, but Id be for some stricter usage of the dammed material. A member above mentioned we can substitute glass/alum cans for packaging- Well, this at least is more eco friendly.

 

Not to mention some regulation (govmt again) with products that pollute so bad in the oceans- skin care products for example- these exfoliants. Contain plastic! Who woulda guessed! This plastic, which is so finely ground up (necessary to do its job on women's skin to help abrade off their layer of dead skin- like it really matters), goes down the drain to the oceans. Researchers have found such a material in the stomachs of jellyfish, etc, who mistake the stuff for planktonic foods.

 

I say ban the cr++. Studies have shown that this convenient material, like many others will not go away cuz people/markets are too addicted. Its gonna take a catastrophe. Human nature.

Edited by pippo
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Can you please give us the reference for the "garbage patch" study you mentioned?

 

Regulatory prohibition of plastic bags is merely a gesture - effectively an extension of environmentalism. Every religion has its sins.

 

How are skin care products polluting the oceans - man, i gotta hear this one!

 

cr++? What are you talking about? Chromium? Hexavalent chromium salts are already regulated but chrmium is an element. It's kinda hard to ban an element.

Edited by JorgeLobo
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"cr++? What are you talking about? Chromium? Hexavalent chromium salts are already regulated but chrmium is an element. It's kinda hard to ban an element. "

Banning the chromous ion (Cr++) would be roughly as stupid as trying to ban chromium.

I wonder what he really meant.

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Sorry it's over your head SMF, any chance you could elaborate on your childish comment?. I see you apparently can't read or do so poorly. i asked about the so-called garbage patch and please remember some of us are scientists and who look for more credibility than wikipedia, however effective it is for high school students. Anything more than this?

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JorgeLobo, I was making a guess at what Pippo meant by cr++ and I think it is a good one based on the content of his post. Perhaps he will tell us. Because you brought it up, please tell me what your scientific credentials are, I have a Ph.D. and 40 years in biological research and teaching. In my expert scientific judgment the Wikipedia article is quite good because it is properly referenced and linked to further information so the reader can verify sources and pursue further knowledge. SM

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PhD - 30 years in academia and industry. Please understand that claiming priority by education or experience is not very useful but to feed ones ego. Providing data and substantiating ones claims are much more effective. I could add that I was responsible for solid waste policy of a multinational corporation and served on the garbage commission of a major US city for many years terms. But again, these means little if I can't back up my comments and they were largely questions.

 

Your expertise is certainly evident in your post offering the simple comment "crap?".

 

Why not offer a reference that justifies your "expert scientific opinion." In fact, you might read the high school level wikipedia article - it says nothing of these alleged garbage islands - it speaks only of currents. The cutsie link to the cartooned, solicitation for money is silly tho' it's references are informative tho many a bit old. Missed that for the conclusion of 3E6 tons. But I'm sure you have reference that would defend it. Please provide them. That should give you something to do for a few hours.

 

Odd - most folks (at least John and I) with experience in chemistry would identify chromiium as Cr rather than cr and would wonder how pippo got to Cr by way of a whine about garbage. We'd also be interested in how one would ban an element. So alleged expert, what did pippo mean?

Edited by JorgeLobo
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