i am a bit confused about the relationship betwern hydrophobicity and oleophicity, Initially I thought if a material is hydrophobic it should also be oleophilic and vice vera but that doesn't seems to always be the case.
my question is how can I increase the oleophilicity of a polymer that has some acetate groups and hydroxyl groups?
Also, why is Flourine group considered toxic?
If you will block the polar groups by atachment of long hydrocarbon chain (by ester bond) it will be more hydrophobic.
Regards
G
As Grzegorz said, since oils are made of long hydrocarbon chains, putting side groups like steric acid and such will make the polymer more oil-friendly.
While fluorocarbons are hydrophobic they are not oil-friendly. Picture when you put olive oil on a teflon pan, it still will bead up into a droplet rather than spread out. Think of the fluorocarbons as a third type of system, in addition to the oil and water systems we are more familiar with.
Since flurocarbons are so chemical inert and stable, they can persist in the environment for long periods of time, and accumulate up to toxic levels over time if they are continuously leaked into the environment or absorbed by workers. The current thinking is that it is OK if the fluorocarbon chain has 4 or less carbons but it is especially bad when their are 8 carbons. Dupont now has to pay hundreds of millions of dollars to the workers and neighbors of their old West Virginia teflon plant for birth defects, liver disease, etc. caused by 8-carbon fluorocarbon surfactant molecules.
https://www.wvpublic.org/post/dupont-offers-670m-settlement-teflon-chemical-contamination-water#stream/0
Dear all, the oiliophilicity is enhanced more as far as the side substituents lengths and nature become as close as possible to the effective chains lengths and nature of the oil. My Regards
Please see the reference below:
PROCESS FOR IMPROVING THE OLEOPHILIC PROPERTY OF POLYMERS. United States Patent 3579032.
Best Regards
By adding substituents that will enhance the oilophilicity of the material in question.
Dear Fatima Ahmad ,
In addition to what is already said by others perhaps a little more explanation about the two terms hydrophobicity and oleophilicity.
Indeed the terms seem to be closely related. Hydrophobicity is by itself a clear term and as implicated by the meaning of the word indicate a troublesome interaction with water. Oleophilicity means literally a love for oil. Consequently oleophobicity means a troublesome interaction with oils (if any).
See for example:
Enhancement on the Surface Hydrophobicity and Oleophobicity of an Organosilicon Film by Conformity Deposition and Surface Fluorination Etching
https://www.mdpi.com/1996-1944/11/7/1089
In this paper you see that the idea is that C-H bonds cause oleophilicity while introducing C-F bonds cause oleophobicity due to their higher electronegativity (they basically repel oleic droplets).
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