What is the half-life of most common plastics ?

Question

Ok, if not half-life, then more simply, how long will it last before it biodegrades ?

Answer 1

If exposed to the elements (sunlight and moisture) ANY plastic material will not last more than about 15 years maximum. GE Plastics did an accelerated test about 12 years ago on greenhouse panel (Lexan polycarbonate). This material is one of the best and strongest plastics around. They fouind they could only guarantee the panels to last 10 years.

You can look at any plastic lawn chair, outdoor table, lawnmower cover, greenhouse unit, and see what is happening to them. It may be gradual but it is definite.

Answer 2

There is still not good answer as to how long plastics will persist in our biosphere in one form or another. No one can say how long the carbon chains would hold together. One assume that it is signifiantly less than the half life of the carbon atom.

Answer 3

It depends on the ambient environment and the additive package. Vinyl goes to crap in a year of sunlight. Vinyl house siding has antioxidants, UV absorbers, and free radical quenchers added and will last for decades. Polyproylene filament in light and air crumbles to dust in a week. Put it in vacuum or under inert gas, away from oxygen, and no problem. Add an antioxidant package and it lasts for years.

Almost anything in a landfill lasts forever, including hot dogs and newspapers. Same for a peat bog.

Answer 4

Half-life is a term applied to radioactive material, not plastics.

Half-life means the amount of time it takes for a radioactive substance to lose half of its radioactivity.

Answer 5

Last time I checked, they are not radioactive, and thus have no half life. ~