What causes white plastic to yellow?
Table of Contents
What causes white plastic to yellow?
White plastic turns yellow over time due to a chemical reaction that occurs when it is exposed to light, oils, etc. If your plastic turned yellow from bleach or food coloring, those are actually dye stains.
How does sunlight affect plastic?
Like human skin, plastics are susceptible to degradation due to ultraviolet (UV) light from the sun. With enough exposure, UV light can cause a chemical reaction in the plastic, which results in scission, or severing, of those big polymer molecules.
Why does the sun make plastic brittle?
Because of the chemical structure of polypropylene, it has a high degradation rate when exposed to UV light like the Sun. The light causes the bonds holding the polymer together to break which weakens the plastic.
What characteristics result in clear polystyrene yellowing with age?
Exposure to ultraviolet (UV) radiation may cause the significant degradation of many materials. When polystyrene is subjected to UV irradiation in the presence of air, it undergoes a rapid yellowing and a gradual embrittlement.
What causes ABS to yellow?
Yellowing in ABS plastic occurs when it is exposed to UV light, among other factors, which causes photo-oxidation of polymers that breaks polymer chains and causes the plastic to yellow and become brittle.
What do you do when white plastic turns yellow?
In this case, you can grab a magic eraser and follow these steps.
- Wet the magic eraser with water and wring it out.
- Scrub the plastic with the magic eraser.
- Dip and wring out the eraser as needed.
- Scrub the yellowed plastic with the magic eraser.
- Wipe down with a dry towel.
- Enjoy that sparkling plastic.
Does UV light damage plastics?
All types of UV can cause a photochemical effect within the polymer structure, which can lead to degradation of some sort to the material. The higher energy UVC is the type most likely to affect plastics. Absorbed UV energy can excite the photons in a plastic. Those free radicals can cause breaks in the polymer bonds.
Does UV penetrate plastic?
Long wave UV passes easily through plastic and glass. Short wave ultraviolet light (100 to 300 nm) is used to kill bacteria, hasten chemical reactions (as a catalyst), and is also valuable in the identification of certain fluorescent minerals.
Does UV light destroy plastic?
Does UV damage plastic?
When absorbed by plastics, UV energy can excite photons. This, in turn, can create free radicals. The fact is, lots of pure plastics simply cannot absorb UV radiation, putting your project and its components at severe risk. You can, of course, avoid UV degradation in plastics.
Does UV light turn plastic yellow?
Exposure to UV radiation can cause plastics to change color (turn yellow), crack, break, shatter or even melt! UV radiation was also the source of the yellowing in the case of the medical tubing failure.
Why does oxidation cause yellowing?
Yellowing occurred due to the thermo-oxidative carbonyl formation in the epoxy carbon-carbon backbone via nucleophilic radical attack.