Woolworths (and presumably Coles too?) make a
big deal about their alleged ecologically responsible
shopping bags.     But... are they biodegradable?

No, because they're made from polypropylene.

And they're made in Vietnam!

Degradable plastics are divided into photodegradable
plastics, biodegradable plastics, etc.  Commonly used
degradable plastics include PHA, APC, PCL, and so
on. Polypropylene (PP) does not belong to the category
of degradable plastics.

From the above description of degradable plastics, we
know that the fundamental difference of degradable
plastics is that they can be degraded in the natural
environment, and these degradable substances are
harmless and don't cause any harm to the environment.

PP particles are generally combined with antioxidants
and degradants (for cracking, embrittlement, and
flaking) which are difficult to degrade.

PP takes 20-30 years to degrade, and in the process
will release toxins, polluting the environment and soil.

Apparently, changing the carbonyl content of PP can
make the degradation period of PP plastics around
60-600 days.      Adding a small amount of photoinitiator
(to convert absorbed light energy or UV into chemical
energy) and other additives to PP plastic can quickly
degrade it—providing it's not buried.

So, how do we find out exactly what sort of PP is being
used by Woolworths?  Any floor staff just respond with
a blank look, and its HO has no idea either.

   This raises an obvious question:  Are we being conned? 
   Are their so-called "green" bags genuinely biodegradable
   and ecologically friendly?

      :-/

Research by Associate Professor Karli Verghese from
RMIT  found that if Coles' and woolworths' green
bags were only used 52 times (weekly for a year)
then the impact on global warming was actually
greater than single-use plastic bags.

She said a green bag needs to be used 104 times
(weekly for two years) to make it worthwhile.

Her study found it took more material and energy to
make the green bags than ordinary single-use
plastic bags.  Calico bags made from cotton are the
only reusable bags likely to be better for the environment
than single-use plastic.

One of the issues with that usage is of course the green
bags' longevity, which invariably means they'll fall apart
long before 104 uses—due mainly to their crappy stitching.

Another problem is that non-woven polypropylene is
fragile, so the green bags can't be cleaned in a washing
machine, but have to be gently hand washed.  Either
way, they release plastic nanoparticles, which end up
in the sea.  Not good.

Most of the Green ideas are only virtue signalling.

Bobby. wrote on Nov 29^th, 2023 at 2:23pm:

Most of the Green ideas are only virtue signalling.

Yes, I'd agree with that.  Most of the so-called "green"
promotion from Coles and Woolies is nothing more than
a sop to people who don't know any different.

It's the same with those thin off-a roll-plastic veggie
bags that Woolies make a big deal about—they're
still plastic, recycled or otherwise.  And they're gonna
end up in land fill.

All supermarket bags regardless of size or purpose
should be made from recycled paper.

Paper can be recycled (repurposed) from 5 to 7 times. 
The only "problem" for Coles and Woolies is that
paper is more expensive, but they should be forced
by legislation to carry that cost themselves and not
pass it on to the consumer.  That's of course if the
supermarkets were genuine in their alleged "green"
causes.    A big IF however.

Which of course, they're not.  Their profit margin and
shareholder dividends is all their bean counters care
about, and bugger the environment.

AusGeoff wrote on Nov 30^th, 2023 at 10:56am:

Bobby. wrote on Nov 29th, 2023 at 2:23pm: Most of the Green ideas are only virtue signalling. Yes, I'd agree with that.  Most of the so-called "green" promotion from Coles and Woolies is nothing more than a sop to people who don't know any different. It's the same with those thin off-a roll-plastic veggie bags that Woolies make a big deal about—they're still plastic, recycled or otherwise.  And they're gonna end up in land fill. All supermarket bags regardless of size or purpose should be made from recycled paper. Paper can be recycled (repurposed) from 5 to 7 times.  The only "problem" for Coles and Woolies is that paper is more expensive, but they should be forced by legislation to carry that cost themselves and not pass it on to the consumer.  That's of course if the supermarkets were genuine in their alleged "green" causes.    A big IF however. Which of course, they're not.  Their profit margin and shareholder dividends is all their bean counters care about, and bugger the environment.

I like my food supplied protected by plastic.

Example:
I don't buy meat at a butcher shop.
I mean - for how long has been sitting in the window and landed on by flies?

In the supermarket it's sealed in plastic and it has a use by date.
That way I know I'm not eating rotten meat.

why is anyone still using bags?