On 13:04 23 May 2021, Chris Hogg said:
On Sun, 23 May 2021 11:55:07 +0100, The Natural Philosopher
wrote:
On 22/05/2021 20:04, Pamela wrote:
On 18:59 22 May 2021, charles said:
In article ,
Pamela wrote:
Amazon/Morrison's deliver frozen food with ice packs containing
some fluid which doesn't stay frozen in my freezer.
What liquid are they using and do ice packs have any use once
the frozen food has been delivered? Seems a shame to throw them
away.
It is probably "Dry Ice". Frozen Carbon Dioxide. Your freeze°r
would need to beta -78°C to keep it frozen ;-)
It's not dry ice. When the ice pack drops to domestic freezer
temperature, the content becomes a slightly viscous fluid.
It's a translucent pouch.
Probably water and some sort of antifreeze
Apparently many freezer packs use a high MW polyacrylate to raise
the viscosity of the water, and prevent it freezing.
This, from https://en.wikipedia.org/wiki/Ice_pack
"Gel packs are often made of non-toxic materials that will remain a
slow-flowing gel, and therefore will not spill easily or cause
contamination if the container breaks. Gel packs may be made by
adding (Cellusize),[2] sodium polyacrylate, or vinyl-coated silica
gel."
The alternative is conventional 'antifreeze', ethylene glycol, but
because of its potentially toxic properties, it has generally been
phased out. This, from
https://www.poison.org/articles/what...-ice-packs-201
"Some early reusable ice packs contained very toxic substances such
as diethylene glycol or ethylene glycol (antifreeze). These types of
ice packs have been recalled and are generally no longer available."
The alternative explanation is that Pamela's freezer isn't working
properly. As has been said elsewhere in this thread, she should
check the temperature with a digital thermometer. If one isn't
available, see if the ice pack goes solid in a friend's freezer.
The freezer is working well, as confirmed by a couple of thermometers
which showed -22C when I put it on fast freeze. The contents of
Amazon's chiller pack remained completely liquid.