Now there are two very basic types of organic solvents;...polar and nonpolar. OS liquids with a dielectric constant of less than 15 are said to be nonpolar. Those with a very high dielectric constant are said to be polar. This is important to us because it helps us to choose the best OS for the job. Since like dissolves like, deposits that are very polar require very polar solvents to dissolve them. The opposite is also true. Most oils and waxes are very nonpolar. Hence they require very nonpolar liquids such as hexane to dissolve them. It follows from this that it is important to determine exactly what the polarity of the substance being removed is. Then match that with the right OS with the same polarity. A quick search on the net will reveal the dielectric constant, and therefore the polarity of both the substance to be removed and the OS needed to dissolve it.
There are also protic and aprotic polar solvents. Protic solvents work well with negatively charged solutes. While aprotic solvents work well with positively charged solutes. The solute being the substance in need of being removed/ dissolved. You can find quick lists of protics and aprotics on the net. Remember any OS with a dielectric constant in excess of 15 is polar. Less than 15 is nonpolar.
Some other properties we might want to look at are melting point, boiling point, autoignition temperature, and water solubility/miscibility. The melting point is also the temperature at which the OS will become rigid or form a solid. Which is difficult if not impossible to work with. So a melting point of zero Fahrenheit would be nice since the solvent will be in a liquid state from zero and up. The boiling point is the temperature at which the OS becomes a vapor or gas. Since there are times we are working on very hot glass it would be good to have an OS with a relatively high boiling point. Anything above 250 Fahrenheit would be perfect. So a solvent with a melting point of zero and a boiling point of 250 means that our OS will be liquid from zero to 250 Fahrenheit. Next a solvent with a very high autoignition
temperature will not automatically ignite without notice. It will not flash in our face without warning. If our OS were soluble or easily emulsified in water it will be easy to remove from the window once it has done its job. Lets next take a look at an OS that comes from the rind of an orange. It is gaining much attention in the cleaning industry because it is relatively nontoxic yet powerful enough to dissolve many hydrocarbon based substances. It has a boiling point of 349 Fahrenheit. A melting point of -140 Fahrenheit. (So it is a liquid between -140 and 349) A flashpoint of 110 degrees. Autoignition temp of 458. Although it is not soluble/miscible in water it can be blended with certain synthetic detergents so that it is easily emulsified by water. The dielectric constant is 2.3 as it is an aprotic nonpolar solvent. It is used as a paint stripper and a cleaner. It is actually possible to add it directly to water if it has been emulsified with the correct nonpolar solvent. It is easy to remove from glass with any cleaning solution. And is very effective at dissolving most non polar aprotic organics. It will soften water based paints making them very easy to remove with a plastic compositional abrasive. This way we can get away from using a razor on bad tempered glass. Just apply the product, wait a few minutes, and rub the paint. Then soap up the window and squeegee it off. It also softens fully cured silicone caulk (this is not a hydrocarbon but is rather based on an Si-O repeater backbone chain). When blended with a plastic compositional with a particle of about 100 microns it will dig through silicone caulk. Also it can be added directly to a microcrystalline silica for removing every last molecule of silicone from glass. Further it will soften fully cured oil based paints. And works on many other hydrocarbons.
I am in the consulting business of developing what I call custom transformer products for the window cleaning industry. The turnkey for these products is the PDR.
The Product Development Review on "Orange Power" gives all the information of the ingredients and where to purchase them. Along with the formulas of how to put it together. This is a two to three page PDF electronic newsletter sent by email attachment for 35 dollars.
Written by Henry Grover Jr.
henrygroverjr@gmail.com
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