quest
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PVA --> PVC
Hi, my knowledge on polymers is very low.
I want to make Polyvinyl chloride (PVC) and the cheapest material I could think of to start with is Polyvinyl acetates (PVA).
Is there any way to synthesis the PVC from the PVA?
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kclo4
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it looks like you could add hcl to it
[C4H6O2]n + hcl = [C2H3Cl]n = c2h4o2
mind to tell me why
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JohnWW
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PVA also means polyvinyl alcohol, a water-soluble usually low-molecular-weight polymer used as a glue.
In view of the reaction with simple monomeric primary and secondary alcohols to produce alkyl chlorides (and with carboxylic acids to produce acyl
chlorides), it may just be possible to convert a grade of polyvinyl alcohol, of sufficiently low molecular weight to dissolve in a mutually suitable
polar solvent with a reasonably high boiling-point and which does not contain -OHs or labile Hs, to the corresponding low-molecular-weight PVC polymer
by reaction with thionyl chloride, SOCl2. Byproducts would be SO2 and HCl. Possible solvents for such a reaction are dioxane (and other ethers
although ethyl ether would be much too volatile), ketones (acetone may be too volatile), carbon tetrachloride, dimethyl sulfoxide. It may be possible
to do the reaction by adding the polyvinyl alcohol directly to the SOCl2, which is liquid up to 78.8ºC, but this is about the temperature to which
the mixture has to be heated under reflux for the reaction, and there may be a danger of excessive heat being generated resulting in SOCl2 boiling
away.
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neutrino
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Why do you want to make your own PVC? It’s readily available in the form of big, cheap pipes at hardware stores. As for your reaction, it would look
like this:
[-CH<sub>2</sub>-CH(OOCCH<sub>3</sub> -]<sub>n(s)</sub> + nHCl<sub>(aq)</sub> -> nCH<sub>3</sub>COOH<sub>(aq)</sub> +
[CH<sub>2</sub>-CHCl-]<sub>n(s)</sub>
The reaction might work, but due to the fact that PVC is a solid, it would be confined to the surface of the chunk of PVA you’re trying to convert.
You might be able to find an inert solvent that would dissolve the PVA, but I doubt it would be OTC.
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quest
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| Quote: |
Why do you want to make your own PVC? It’s readily available in the form of big, cheap pipes at hardware stores
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I want pure PVC, and pipes are too contaminated.
And at my chem store its very expensive.
As for using HCl but I was told it wont work :-/
I will try it and see what happen 
BTW, is there any indicator for PVC?
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Rajinder Singh Gujral
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CONVERSION OF pva to pvc
Commercially viable method is avaialble for this conversion using Thionylchloride and DMF ( as catalyst). PVA is heated with these and finally
distilled to get pure PVC.
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