I haven't dealt with PVOH before, only with PV-Acetate, which this
obviously is not.
PVOH is readily available and cheap, so it would not be difficult to
try if someone just can't find the right glue.
ST
On Sun, Jul 8, 2012 at 2:05 PM, Robin Whittle <rw@...> wrote:
> Hi Stefan,
>
> Thanks for finding the MSDS for the "paper gum" glue I used:
>
> .
> http://www.chemquest.com.au/cgi-bin/cq_add_msds.pl?action=showMSDS&productName=CRAFTSMART%20PAPER%20GUM
>
> The search function there does not seem to be working at present. A
> link on that page leads to the ingredients:
>
> .
> http://www.chemquest.com.au/cgi-bin/cq_add_msds.pl?action=showMSDSIngredients&productName=CRAFTSMART%20PAPER%20GUM
>
> This states "Poly Vinyl Alcohol 10-15%" with a small proportion of a
> biocide, to stop it going mouldy. I guess the rest is water.
>
> PVOH means, I think, Poly Vinyl Alcohol which can also be known as PVA,
> but which is different from Poly Vinyl Acetate.
>
>> Apparently this is a PVA glue after all. Does it smell right?
>
> It is not an emulsion, like milky-white wood glue which I understand is
> a water emulsion of some hydrocarbon solvent with Poly Vinyl Acetate in
> that solvent. It is a clear, free-flowing, but viscous, uncoloured
> fluid. I cannot detect any smell.
>
> I dribbled some on a piece of glass and put it in the gas oven for 20
> minutes or so at 200C. What remained was about 20% of the volume, and
> was clear and slightly brown. It is hard and stuck firmly to the glass!
>
> What remained softened with water. Perhaps it would dissolve in water too.
>
> This does not look like any kind of starch. I assumed it was starch so
> I tried it. It seems Poly Vinyl Acetate:
>
> . http://en.wikipedia.org/wiki/Polyvinyl_alcohol
>
> melts at 230C, but this would depend on its molecular weight. The
> boiling point is quoted as 228C, which makes no sense to me.
>
> This melting temperature is, I assume, above that of laser printer fuser
> rollers, so it will probably work OK.
>
> Here is a page describing Poly Vinyl Acetate as a glue for bookbinding,
> as a 20% solution in water:
>
> . http://cool.conservation-us.org/byauth/woods/pva.html
>
> once cooled, it is a stiff jelly. This doesn't match the glue I have here.
>
> - Robin
>
>
>
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