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I need advice of how to clean plastic without produce cracks and white haze on them in plastic, exactly in:

-Polycarbonate -Polyethylene -Polystyrene -ABS

Basically the materials of optical media (CD, DVD, Bluray), their cases and videogame console plastics

I thought that Isopropyl alcohol mixed with distilled water could make the work, but i read that in labs, the polycarbonate parts of computers are clean with Ethanol due to can be damaged in some way on the long run (Source: https://labproinc.com/blogs/chemical...ics-in-the-lab)

But the compatibility charts of the materials reports that Ethanol alcohol is just "good" and Isopropyl alcohol is "excelent"

Some studies of optical media even recommend the isopropyl alcohol to clean it (Source: https://www.clir.org/pubs/reports/pub121/sec6/)

But, in other hand, the optical media manufacturers, recommend put in discs only water

Right now, i am a little confuse, what do you recommend to use to clean plastics without damages like paint strip, cracks or white haze?

In case that alcohol do the work, ethanol and isopropyl dry fast? When it dry it becomes the plastic flammable?

Thanks in advance

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    $\begingroup$ I would renounce to ethanol, because commercial ethanol (spirit) is often mixed with 1% impurity that makes it undrinkable when mixed with water to produce liquors like vodka. These impurities have practically no effect on chemical reactions of ethanol, but they can remain adsorbed on plastics. Isopropanol is purer than usual ethanol. $\endgroup$
    – Maurice
    Jul 17 at 15:33
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    $\begingroup$ If in doubt, a damp washcloth and some elbow grease. Plastics do not all behave the same, obviously, so there may not be a single ‘best’ cleaning agent for all of the plastics you mention. $\endgroup$
    – Ed V
    Jul 17 at 16:40
  • $\begingroup$ It isn't possible to generalise as the variety of polymers and formulations is too large. But one solution is to test samples of each polymer before committing to a specific cleaning agent (CDs and DVDs are usually polycarbonate, so test an old useless one with the solvent you have and see if it deteriorates). But start with isopropanol as it is widely available as a pure solvent and often works. $\endgroup$
    – matt_black
    Jul 19 at 10:44
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The washcloth suggested by Ed V could be dampened with plain water, or with solvent, for example, diluted isopropanol.

The amount of dirt and grease you will be dealing with, in 95% of cases, IMHO, is something that can be wiped off, rather than requiring dissolution of the gob. If you have a gob of dirt/grease, remove most of it mechanically, then gently mechanical (the washcloth), then with a reduced surface tension liquid. Avoid thinking that dirt and grease must be dissolved - they need only to be removed.

Low surface tension materials include solvents, but it has been noted that many plastics are degraded by solvents. Pure solvents are usually flammable (and often toxic). Diluting the solvent with water can still result in a low surface tension liquid, with the added advantage that the water will reduce the tendency of the solvent to penetrate (i.e., dissolve) the plastic. Diluting the solvent will be safer, cheaper, less damaging, and almost as efficient, requiring only a little more elbow grease. The figure shows how surface tension stays low even when solvents are diluted with water:

enter image description here

There is no absolute guarantee that dilution will solve all your problems; some risk is always involved. For example, even using diluted acetone to clean polystyrene would be a no-no.

And there is one more approach: use a diluted surfactant for your cleaning liquid. The lowest surface tension achievable by surfactants is often reached at concentrations of less than 1000 parts per million - that is 0.1% by weight. At this point, it is the water that could damage sensitive electronic equipment, so dampen the washcloth, don't soak it.

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  • $\begingroup$ Thanks for the answer, i think that i understand what you point in the tecnical text, basically, the dirst must be removed, not disolved, with water or isopropanol. So, i think that in a order, the best option would be: Only distilled water, followed of the option of a mix of distilled water and isopropanol at 50/50, and the most sturdy ones with a mix of distilled water and soap, due to water low the tension of the disolvent, and is more safe to apply, but the mechanical effect do more work that even the disolvents. I am wrong with the interpretation? $\endgroup$ Jul 20 at 13:23
  • $\begingroup$ Well, your way is safest. But to be faster, I would try 25% isopropanol in water (tap water might be OK) or 0.5% dishwashing liquid in water. You might make up a bottle of each and see how they work for you. This way, if the isopropanol solution is good but not great, you could add more, up to ~50%; same with the detergent (up to ~1-2%, not 50%!). Experiment. Water alone is good, if it works, and you don't use too much - but probably not very effective. $\endgroup$ Jul 20 at 13:47
  • $\begingroup$ I will mix them and I will check, the distilled water more than anything is to be as pure as possible, although... It said that distilled water is more acidic. Would it affect the mixture in something? And about where to mix it ... I had thought of some plastic perfume-type spray bottles, to control the amount expelled from the container. But would there be a better option to mix it? Some glass maybe? And again, thanks for the answer $\endgroup$ Jul 20 at 23:21
  • $\begingroup$ Oh, and another point, ethanol could be a substitute for isopropyl? Isopropyl is not so easily found in my area, but ethanol is, hence the question. I mean, i understand that Isopropanol is just Isopropyl alcohol not? $\endgroup$ Jul 20 at 23:32
  • $\begingroup$ See Maurice's comment about ethanol. Get isopropyl alcohol rubbing alcohol from your grocery store. Spray bottles are OK if you spray onto the washcloth, not the plastic. $\endgroup$ Jul 21 at 13:27

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