Wow is right.

I'm not a chemist, but I am a chemical engineer, so maybe that's close enough.

It could have been a bad batch, like ST says. More likely, the "formula" changed, and it just wasn't tested sufficiently. Maybe that was because the test person was slime and deadlines, career advancement, or profits came before thorough testing. Or maybe the test person was just dumb, and the mistake wasn't caught because the test person's boss was dumb too (or maybe slime). Or maybe everyone at Kiwi did a conscientious and thorough job, but the third-world shoe manufacturers all switched to a new, cheaper kind of glue that dissolves in boot protector. Who knows?

First thing I'd do is check to be 100% sure it's the boot protector that's the problem. If you still have the boots, spray the protector on the glue and confirm that it dissolves. Then contact Kiwi. They might take the high road (remember Johnson & Johnson and the tampered Tylenol), or they might give you the runaround (more likely: send us both pairs of boots at your cost, plus the protector and we'll look at it ...)

I appreciate your bringing this to our attention!

Wow

I've used silicone spray for years ( not that brand) and had never had an issue.

I'm wondering if that can/batch wasn't contaminate with something or formula was off?

What's the odds two different make shoes would have that reaction.

Somebody here is a chemist ( I think) maybe they'd know.

I bet the boot mfger would be shocked to know a product made/sold for waterproofing boots could do such a thing in that short of time.

KIWI Boot Protector - "Tough silicone protection for work and outdoor boots.  Ideal for work, hunting and other outdoor boots"

my experience is far less than ideal, since this stuff trashed two pairs of hunting boots in four days of hiking use -  apparantly the silicone has some reaction with the rubber soles and the soles just about dropped off the boots.

case 1 - a good pair of Irish Setter field boots (glued on soles) - I'd used these maybe a dozen days or so, and decided to spray on some waterproofing to get them ready for my Elk hunt - they hadn't leaked, but I figured some more waterproofing wouldn't hurt, right ?  backpack up a couple thousand feet and 3 1/2 miles on Friday evening, and hunt moderately hard on Saturday - that evening when I take my boots off in the tent, I see that the sole on the right boot is half ripped off - like the rubber had rotted.  bummer, so in the morning, I wrap some string around the boot and sole and hunt for about half a day, then pack out back to the truck.  I get to the truck, and now the second boot has done the same thing!   damn! never had that happen before - maybe it was the waterproofing spray?

case 2 - so that was labor day weekend, and last week, elk and turkey hunting, I brought a brand new pair of Kamik hunting boots - nylon uppers that were supposed to be waterproof, but seemed to leak at the tongue (I'd used them one day previously in wet brush)- so I had stupidly sprayed on the Kiwi Boot Protector thinking that It propbably wouldnt' hurt a second pair of boots by a different manufacturer - wrong!  I had worn this pair of boots one day previously, right our of the box - so last Saturday was only the second time I'd put them on - halfway thru the day, I see that a 3" chunk of the sole on the toe has ripped and is starting to come off from the right boot, and did just peel away.  well, I'm pissed, but keep hunting in rough terrain and about mid afternoon, I notice that now, the sole on the left boot is starting to peel away at the heel. double damn! - so i wrap it with string and continue hunting, but hunt my way back to the logging road and have a 4 mile trek back to the truck - had to stop and retie the sole on several times, and got back to the truck with only about 10% of it still attached at the toe, the rest just flopping along - strangely, the right boot, with the chunk of sole missing from the toe still has the rest of the sole attached.

never had the likes of that happen ever before - I had previouldy used Kiwi spray product - "KIWI Performance Fabrick Protector" on boots and never had that happen - looked at that nearly empty can (which was why I bought the new can of boot protector) and it says "non-silicone polymer"

must be the silicone isn't compatible with the rubber soles of the hunting boots I had - there was no word of caution about it on the can, and it fact it said "spray entire boot" - I didn't deliberately spray the stuff on the soles, but there was just some spary that got on top of the rubber where it met the nylon uppers

so a word of warning if you use this product, or are thinking of buying spray waterproofing for your boots - don't use the KIWI Boot Protector product or you risk trashing your boots.

I have not contacted KIWI yet or the boot manufacturers, but will be doing so - I'm especially curious to know if other people have had the same problem.