Plastic materials like mugs and buckets are very soft and easily pliable. But after use become brittle and crack from different places. Why is it so? Is it to do with contact with water or atmosphere or anything else which makes the difference. Does it mean that plastic is to some extent degradble with atmospheric effects?
2006-10-10 08:54:55 · 6 answers · asked by Let'slearntothink 7 in Environment
Most plastics are not really a single substance but are a mix of several different substances.
Part of the mix are chemicals that help make the plastic more flexible - these are actually called "plasticizers". Most plasticizers tend to gradually move out of the plastic and evaporate. So, over time, the plastic gets less and less pliable and more and more brittle.
Evaporating plasticizers are a large part of the odor of a new car - you are mostly smelling the plasticizers that are evaporating from all of the new plastic surfaces.
2006-10-10 09:05:12 · answer #1 · answered by Carbon-based 5 · 1⤊ 0⤋
There are four general causes that I am aware of:
1. Ultraviolet light. It's strong stuff, and affects some plastics, but not others.
2. As previously mentioned, the plasticizers in plastic (love that logic eh?) can leach out or degrade in some formulations. Without these, the plastic gets brittle. Heat can accelerate this.
3. Mechanical stress: repeated deformation past the elastic limits of the material can break it down.
4. Plastics are organic chemical mixes that can be degraded by exposure to chemicals in the atmosphere and environment. Ozone is a nasty culprit. (A component of urban smog.) Other chemicals-solvents, strong bases, oxidizers love to chew up plastics.
Water in my experience doesn't degrade most plastics, or even any that I know of in common use. The chlorine, ozone, or other things in the water might do so though.
Happy plasticing!!!
2006-10-10 16:58:28 · answer #2 · answered by Pnutsmom 2 · 0⤊ 0⤋
Brittle Plastic
2016-10-16 07:24:39 · answer #3 · answered by ? 4 · 0⤊ 0⤋
Product Design and Heat from plastic processing; Temperature different and Shear stress from Injection Molding, Inherent stress after pressure , etc.,
2014-08-03 01:44:16 · answer #4 · answered by CHERDTHAWAT 1 · 0⤊ 0⤋
I think it has more to d w/ the temperature. The constant heat and cold changes as molecules are trying to expand and contract. Also the sun can break it down also
2006-10-10 09:04:34 · answer #5 · answered by tera_duke 4 · 0⤊ 0⤋
some plastics react unfavorably with sunlight, they aren't actually degrading
2006-10-10 09:03:08 · answer #6 · answered by Anonymous · 0⤊ 0⤋