A cocktail of sealants

Very often the early solidification of latex sealants is due to contamination by other liquids. We describe here below common and unexpected contaminations sources.

The common reasons for polymerization of latex (synthetic or natural) sealants can be macroscopically divided into physical (related to temperature changes or evaporation, described in details in specific tech news here (Caffélatex, Végétalex and CO2, or Espresso) and here (Caffélatex and the “hair dryer” effect) or chemical ones (mixing with other products)... but they all lead to the same: alteration of the pH of the liquid, leading to the beginning of solidification.

Any sealant has a specific pH value and it mostly remains liquid as long as the pH doesn’t get outside a certain range. 

Mixing sealants intentionally

A quick way to change the pH of a sealant is mixing it with other liquids. We call these liquids ‘sealant contaminants’, with a negative connotation, because their addition is normally unwanted. By contrast, Caffélatex ZOT! Nano takes advantage of a sudden pH variation on purpose, in order to set solidification of Caffélatex and instantly repair damages to the tyre.

Some people mix sealant intentionally but, contrary to popular belief, randomly mixing sealants is unlikely to give the ‘silver bullet’ of puncture protection; most of the time this mix will simply shorten the lifespan of the sealants.
As it’s a common question: we formulated Végétalex sealant to be compatible with Caffélatex, so that mixing them won’t create unusually early solidification (although the mix will have the lifespan of Caffélatex, not of the more durable Végétalex). We still recommend to mix Caffélatex and Végétalex only if transitioning from one to the other, and use either one or the other down the road.

Mixing sealants by mistake

In addition to these deliberate mixtures, it happens sometimes to mix sealants unintentionally:

• by pouring a sealant into a tyre already partially filled with another liquid sealant (to be safe, it’s always better to remove the tyre, wash it with water, dry it out, and then add the sealant);
• using an inflate & repair cartridge, the resulting sealant will have an unpredictable lifespan (unless cartridge sealant and tyre sealant have compatible formulas, like our Espresso or Espresso Doppio cartridges and Caffélatex or Végétalex).

Generally speaking, mixing different sealants during a ride it’s not a problem, because the sealant mix still works long enough to potentially repair the puncture. Anyway, once back home it’s always better to wash away the remaining sealant, then pour fresh sealant.

Glitters or other solid fillers (like our Vitamina CL) do not chemically influence the sealant, although they could have a negative effect when not properly mixed as polymerisation starters.

Soapy water is another common contamination cause: it’s ok to wet the tyre beads to get a better seal and achieve an easier inflation, but the risk is to use too much water and/or the wrong product. Dishwashing liquids or kitchen detergents usually shorten the sealant lifespan. Furthermore, if too much soapy water remains inside the tyres and mixes with the sealant, it will reduce the ability of the sealant to repair the punctures.

We recommend using specific tyre-mounting products or mild hand soaps.

To verify the compatibility, pour some drops of detergent on a teaspoon of sealant and let it rest for a few minutes: if the sealant turns solid, use a different soap.