OK, lots of guesses, but most of you focused on the much-debated monkey business of the tubular gluing process, rather than the properties of the glue like I noted. Over on the salon the topic of thinning Mastik 1 came up. Having spent way too many years of my past life testing and analyzing adhesives as part of my old job, rather than listen to the mindless banter and lore on the forum, I set out to determine the real answer as to what Mastik1 is. Except I don't work in the lab anymore, and never paid attention in high school chemistry class (that would have required actually attending high school...)
Anyway, Mastik1 lists "natural rubbers" and hexane as ingredients. Natural rubbers are the kind that comes from trees - very low tech. These kinds of adhesives are known for very high tack (stickiness) and peel strength (sounds good, right?) but piss-poor (that is a highly technical term) heat resistance and shear strength (aka "splitting" or leaving residue on both adhered surfaces). We made stuff like underhood labels for Honda and Toyota, as well as that holographic "Intel Inside" sticker on the PC you're probably staring at. As such, we used more sophisticated acrylic resin polymer formulas, and I don't know much about crude rubber-based PSAs. Not that I know all that much about anything.
Since Mastik1 contains hexane, I believe it is a solution. Someone on the salon claimed it was a dispersion or colloid, but I don't think that is true. Some rubber-based adhesives are aqueous emulsions (i.e. latex, including even Jevelco Tire Life) but those are easily identifiable by their milky-white appearance). But I digress. In my investigation, I learned a new word - Mastication. Now you know the answer to the puzzle, as well as the etymology of the Mastik1 name. You see, in the tree processing industry "masticating" is a mechanical chewing/grinding of the pulp product. This is done in the process of making natural rubber products, like tire glue. I welcome comments from the chemistry experts in the audience as to whether or not they're truly soluble in hexane or not. Thanks for reading monkey people!
Oh yeah, I will get to the weekend sequel tonight.
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