Does PVA have a shelf life?

[accipiter]

May be a strange question but I'm asking as I found a 5Lt container of PVA glue in my workshop that I'd forgotten about - - - not having been *wood* working in there for a number of years! The container must be from something around 23+ years ago. I'm therefore wondering if it is still a *viable* product for use? If it's still a viable item is there a way to "re-constitute" it by adding some water to it?

It is rather 'globular' when poured from the bottle - quite thick to spread and not runny at all. I've tried some on a couple of bits of wood as a test and they are fixed together but I didn't like the thickness of the glue when getting it from the container and spreading it out. I don't know if it is a "normal" PVA or a "Waterproof" type - can't remember acquiring it those 23 years + ago...

 

[Phil Pascoe]

Use it for coating your garage floor or for mixing with mortar or something. I's not worth the risk on something you've put hours of work into.

 

[Rorschach]

As above, I use old PVA for art projects etc, never trust it on a wood working project. I buy my "good" glue in small bottles for precisely this reason.

 

[sometimewoodworker]

May be a strange question but I'm asking as I found a 5Lt container of PVA glue in my workshop that I'd forgotten about - - - not having been *wood* working in there for a number of years! The container must be from something around 23+ years ago. I'm therefore wondering if it is still a *viable* product for use? If it's still a viable item is there a way to "re-constitute" it by adding some water to it?

It is rather 'globular' when poured from the bottle - quite thick to spread and not runny at all. I've tried some on a couple of bits of wood as a test and they are fixed together but I didn't like the thickness of the glue when getting it from the container and spreading it out. I don't know if it is a "normal" PVA or a "Waterproof" type - can't remember acquiring it those 23 years + ago...

You can thin most, if not all, PVA glues with a little water. Here the standard is thicker than double cream but thinner than clotted cream, possibly a not too warm golden syrup. I keep one bottle thinned a bit. So yes put a little in a different container an add a tiny bit of water, if it mixes well then if needed you can add a bit more water and if it’s too runny you can add in a little more of the thicker stuff.

My opinion is that if when mixed you get a smooth non lumpy glue I would use it, if it is lumpy then it’s due to be binned.

 

[Peter Sefton]

As a general rule PVA would have a shelf life of 2 years, I have some which is to be used within 3 months. Also bare in mind PVA is not great if it's had a hard frost.

Cheers

Peter

 

[accipiter]

I will certainly try your suggestion @sometimewoodworker - thanks. I was thinking of trying that but thought I'd ask others just in case I was wasting my time after 23+ years. It doesn't have lumps in it... it os just *very thick*.

If it doesn't do well even then I'll use it in some cement or on the workshop floor when I do it next year @Phil Pascoe - thanks for your input.

 

[accipiter]

As a general rule PVA would have a shelf life of 2 years, I have some which is to be used within 3 months. Also bare in mind PVA is not great if it's had a hard frost.

Cheers

Peter

Thanks @Peter Sefton - guess I'm pushing it a bit then a 23+ years... The container doesn't have a use by date on it though...
Thanks for your input.

Frank

 

[Peter Sefton]

Thanks @Peter Sefton - guess I'm pushing it a bit then a 23+ years... The container doesn't have a use by date on it though...
Thanks for your input.

Frank

They didn't put use by dates in the late 90's as the millennium bug was going to bring the world to a crashing end anyway

 

[accipiter]

They didn't put use by dates in the late 90's as the millennium bug was going to bring the world to a crashing end anyway

Yeah... I remember that time... and had a good laugh about it all

 

[johnnyb]

it definitely does go off.( once it's gone globby it means it's started to cross link and is useless.)

 

[accipiter]

it definitely does go off.( once it's gone globby it means it's started to cross link and is useless.)

Okay... thanks @johnnyb

 

[sometimewoodworker]

Okay... thanks @johnnyb

There is a considerable difference between the consistency of “gone off” and needing a bit more water.

if it’s gone off adding water will not give a smooth consistency, and it will be stringy, and you will not get good adhesion in part due to the strings preventing good joint closure. I also doubt that it will be any good adding it to concrete if it’s truly gone off, in that case the only useful thing is the bottle, the content is just for the bin.

As a general rule PVA would have a shelf life of 2 years,

That is a rather sweeping statement. It’s certainly possible that there could be different formulations that have that kind of shelf life. The brands available here are certainly usable far beyond that, though being stored in almost full bottles may help or be required. I have used a bottle, that I forgot tucked away, that was around 9 years old. the joints I used it on are as good as any other.

None of the containers I have have use by dates they only have production dates.

Also bare in mind PVA is not great if it's had a hard frost.

Luckily that is a problem that never happens here. We are fortunate if we get more than a few days with the lowest night time temperature under 15C and then I can wear a long sleeved shirt around the house in the day time without running the AC on fridged mode

 

[planesleuth]

My experience is it depends on the manufacturer of the glue, whether they are worthy of their title or a just bunch of sc*****. Below 50 degrees destroys all PVA in my opinion and so as has already been said; not worth the risk. Croda used to be the best, not sure now. I always use Howdens branded PVA and always bring it indoors during winter.

 

[sometimewoodworker]

Below 50 degrees destroys all PVA in my opinion

Are you sure? 10C seems quite a high temperature to kill off glue.
How long do you consider to be enough time to kill it?
it is certainly easy to test your hypothesis as everyone has a device that holds a temperature above freezing and under 10C (unless it’s broken) usually around 4C~5C, they are even common here in the back of beyond as long as there is a power supply

 

[Phil Pascoe]

That is a rather sweeping statement. It’s certainly possible that there could be different formulations that have that kind of shelf life. The brands available here are certainly usable far beyond that ...

It's a hot Country - you probably don't get the formulations that are adversely affected by heat. I use Everbuild D4 for most things - I have to baby it get more than six months from it (I usually finish it before that, though.)

 

[Peri]

I've had pva that's sat in my unheated UK workshop for 3 winters or more. While I wouldn't risk gluing anything up when the temp is below about 10c, once things warm up in the spring it's perfectly fine to use.

(Mainly I use Titebond 3, Gorilla and Evostick pva's)

 

[accipiter]

Thanks all for your input and for participation in this. I really wasn't expecting to cause any fallout between members but appreciate that we each have different experiences.

Yesterday I decided to mix some up with water and put separately in an old drinks bottle. Mixed to a consistency similar to some Gorilla glue I recently purchased. I then used some of the mixture to glue two scraps of wood and will check today to see how it holds up.

As I had some of the mix left that wouldn't fit in the bottle, as an afterthought I put it in the 5lt container and gave a good shake. I was quite surprised that the contents seemed to loosen up! I continued to shake further and checked the contents which seemed to have lost the thickness/globular consistency so will try some of that later today.

Thanks again.

Frank

 

[sometimewoodworker]

It's a hot Country - you probably don't get the formulations that are adversely affected by heat. I use Everbuild D4 for most things - I have to baby it get more than six months from it (I usually finish it before that, though.)

The data sheet for that only lists alcohol and 3 preservatives so it’s far from clear that it is a PVA glue & it isn’t mentioned as that on the website also the thinner is likely to be isopropanol rather than water.

This would also explain the short usage life, as unless the opened containers are kept full there will be evaporation of the alcohol.

 

[sometimewoodworker]

I really wasn't expecting to cause any fallout between members

I haven’t seen any fallout. There are different opinions & experiences also it’s not completely clear if like is being compared to like.

The glue companies don’t list exactly the composition of the products so precise comparison may not be possible and experiences of individual members and glues are not questionable.
I do question the blanket 2 year life span of PVA as from personal experience I have used glues10 times older than that with no problems.

Yesterday I decided to mix some up with water and put separately in an old drinks bottle. Mixed to a consistency similar to some Gorilla glue I recently purchased. I then used some of the mixture to glue two scraps of wood and will check today to see how it holds up.

I look forward to the report, I predict it will be OK

 

[Phil Pascoe]

D4 contains no solvents and is water soluble. It does class it as a "hybrid resin" though, so isn't a normal PVA - PVAs are usually advertised as water resistant not waterproof. Brilliant stuff. 502 is fine as well, with a bit better open time.