[Make it Lady (OP)]

I am treated like I am a smoker or a seal clubber if I ask for a plastic bag in a supermarket but is this really the worst thing chemists ever invented and can chemistry take the green high ground in other ways?

[DoctorBeaver]

I would have thought that napalm, agent orange or bacterial/chemical weapons would rate hgher.

[Make it Lady (OP)]

You tell that to the check out ladies at Waitrose.

[Chemistry4me]

I see that they have developed organic liquids which can capture greenhouse gases

[Chemistry4me]

As far as plastic bags are concerned, plastics have touched our lives in countless ways so there are always benefits as well as its disadvantages. In the future, I think one day plastics will be totally beneficial to all of us.

[Chemistry4me]

There are also rocks to soak up carbon dioxide

[Bored chemist]

The biodegradable plastics were developed by chemists.

[Make it Lady (OP)]

So why don't they make shopping carrier bags from biodegradable plastic?

[Make it Lady (OP)]

There are also rocks to soak up carbon dioxide

Don't mention rocks we might get Geologists on here.

[Make it Lady (OP)]

This is the kind of thing I was after, thanks chem4, I knew I could count on you.

[Karsten]

What kind of biodegradable do you mean? The kind that just falls apart to be pieces too small for humans to get upset about, or the kind that uses non-petrochemical materials and is actually compostable (= digestible by microorganisms)? If there is such a thing as the latter.

[Chemistry4me]

I think the latter...

[Chemistry4me]

So why don't they make shopping carrier bags from biodegradable plastic?

According to a site in NZ:

Biodegradable plastic bags and packaging aren't an end solution to replacing non-degradable plastic bags in supermarkets and retails stores for the following reasons:

•They do not decompose in properly managed landfills.

•They support the throwaway mindset and the use of landfills as an acceptable disposal method

•They do not discourage over-use in the first place.

http://www.zerowaste.co.nz/default,475.sm

[Chemistry4me]

There was also this: [8D]

Bioplastics and biodegradable plastics have long been controversial. Manufacturers like to portray them as a magic-bullet solution to the problem of plastics that won't go away. Bioplastics, for example, are touted as saving 30-80 percent of the greenhouse gas emissions you'd get from normal plastics and they can give food longer shelf-life in stores. But here are some of the drawbacks:

•When some biodegradable plastics decompose in landfills, they produce methane gas. This is a very powerful greenhouse gas that adds to the problem of global warming.
•Biodegradable plastics and bioplastics don't always readily decompose. Some need relatively high temperatures and, in some conditions, can still take many years to break down. Even then, they may leave behind toxic residues.
•Bioplastics are made from plants such as corn and maize, so land that could be used to grow food for the world is being used to "grow plastic" instead. By 2014, almost a quarter of US grain production is expected to be turned over to biofuels and bioplastics production, potentially causing a significant rise in food prices.
Some bioplastics, such as PLA, are made from genetically modified corn. Most environmentalists consider GM (genetic modification) crops to be inherently harmful to the environment.
•Bioplastics and biodegradable plastics cannot be easily recycled. To most people, PLA looks very similar to PET (polyethylene terephthalate) but, if the two are mixed up in a recycling bin, the whole collection becomes impossible to recycle. There are fears that increasing use of PLA may undermine existing efforts to recycle plastics.

http://www.explainthatstuff.com/bioplastics.html

[Chemistry4me]

Why not try and make some Make it Lady? []

A recipe for PLA bioplastics
1)Take some corn kernels (lots of them).
2)Process and mill them to extract the dextrose (a type of sugar) from their starch.
3)Use fermenting vats to turn the dextrose into lactic acid.
4)In a chemical plant, convert the lactic acid into lactide.
5)Polymerize the lactide to make long-chain molecules of polylactide acid (PLA).

http://www.explainthatstuff.com/bioplastics.html

[Chemistry4me]

There appears to be a better recipe here  [] [] [] []

[Karsten]

There appears to be a better recipe here  [] [] [] []

That is a fine video! Is this stuff water resistant?

[Bored chemist]

There appears to be a better recipe here  [] [] [] []

That is a fine video! Is this stuff water resistant?

No, which might be a problem if you are carrying your groceries home and it rains.

[Karsten]

There appears to be a better recipe here  [] [] [] []

That is a fine video! Is this stuff water resistant?

No, which might be a problem if you are carrying your groceries home and it rains.

Or use it to make bags to pick up dog poop.

My groceries go into backpacks or canvas bags.

[blakestyger]

Chemists did not invent the plastic bag - they invented plastics.

Science should be morally neutral and scientists should not be held responsible for the uses to which their inventions are put.