I found some information about it:
What is it exactly?
Look at this YT video (though missing in my opinion 2 great advantages: 1) much easier to work with than silicon (doesn't stick and dry too quickly [edit*]), 2) huge lifespan once opened (it's hard to keep silicon for long time) ).
MS Polymer™ is a water- and solvent-free, clear, odorless solution
and liquid at room temperature. It has low volatility and a low Tg.
When it comes into contact with a catalyst and water, a crosslinked
matrix is formed, providing good heat and chemical resistance.
MS Polymer stands for “modified silicone”, although it is not entirely
silicone-based. It has a polyether backbone with reactive silyl
functionality (telechelic).There are 2 kinds: a dimethoxysilyl (DMS)
with 2 reactive groups (each side) on it and a trimethoxysilyl (TMS)
with 3 reactive groups on it, making it a faster curing system than
the DMS type. The TMS polymer is a newer version which creates a more
strongly crosslinked matrix during curing in order to make harder and
stronger material.
The biggest difference with products common in the PSA and tapes world
is that crosslinking occurs through moisture-curing. So by addition of
a catalyst and subsequent contact with water, MS Polymer™ will start
crosslinking and form a matrix structure. Besides the functionality,
which can be altered by using either DMS or more reactive TMS, the
polyether backbone can also be tuned by varying molecular-weight and
branching. The polymer is telechelic, having 2 ends, but also a
single-end version can be used as a kind of plasticizer. The product
range includes a high-strength grade, meaning that the functional
groups are even denser, creating even harder or higher-strength
material. A mixture of polymers can be used to make many different
kinds of products.
What can you do with it?
This add another advantage to the list above:
MS Polymer™ is mainly utilized in the adhesives and sealants world
where it is a more common technology. (In contrast, silicone is not
actually an adhesive, its adhesive qualities tend to break down much
sooner than those of an actual adhesive *.) Its applications
include sealants and adhesives for construction, automotive and DIY,
such as waterproofing, glazing and insulating.
The polymer is also fairly to very compatible with many rubbers,
acrylics, resins and additives. In other words, it is very compatible
with many components currently used in PSAs to make a tape.
Polyurethane Sealant vs Silicone Sealant vs Polymer Sealant (According to sbdir.com):
- Highly durable – harder than silicone, capable of withstanding high external forces and extreme climatic conditions. Expands and contracts as it’s exposed to the weather. Forms a seal preventing water and air escaping a system. Polymer solutions are typically good for a 5 year warranty.
- Easily Customisable – choose from extensive natural state colour range. Or, simply paint over with your choice of paint, including water-based paints.
- Safe – no isocyanate, does not irritate skin or cause occupational health issues and it is also environmentally friendly.
Aesthetically Appealing – cures smooth, does not bubble or attract dirt.
- Superior Cohesion – adheres to many different substrates, more resistant against expansion/contraction.
- UV Resistant – Polymer can have various blockers, absorbers and stabilisers added to improve UV resistance. This makes it ideal for long-term use outdoors and in sunny environments.
- Heat resistance. I tested it with a heat gun till 400C no visible degradation nor fumes. (Seems great to protect electronic, like Kapton tape)
Unanswered question:
- Does it stick with itself as strongly as other material (I must test this).
Others:
- Don't buy MS polymer that doesn't have an expiration date. I bought several: they cured too quickly (5 min), and 1/3 of the tube had already cured
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