Wikipedia:Reference desk/Archives/Science/2023 August 1

= August 1 =

Alias for inflationary blood pressure measurement
I am studying inflationary blood pressure measurement devices. Because it is rather new, I assume the name of the type of device hasn't settled on a specific term. The devices I've found are all made by one company, Welch-Allyn. I've been trying to find an alias for the device name so I can find similar devices from other companies. By chance, does anyone here recognize this class of devices and know other models? 12.116.29.106 (talk) 11:35, 1 August 2023 (UTC)


 * Do you mean a sphygmomanometer? -- Verbarson talkedits 11:37, 1 August 2023 (UTC)


 * Or maybe this gizmo ? Alansplodge (talk) 12:13, 1 August 2023 (UTC)
 * Yes. That is it. It says it uses linear inflation technology where the devices I was already looking at use the term inflationary. But, at least that is another company making the same type of device. With two companies, I have a better chance of finding competitors. 12.116.29.106 (talk) 13:33, 1 August 2023 (UTC)


 * In the UK, the company that makes almost every blood pressure monitor I've seen is Omron.--Phil Holmes (talk) 14:01, 1 August 2023 (UTC)
 * As in Omron. --jpgordon&#x1d122;&#x1d106;&#x1D110;&#x1d107; 14:49, 5 August 2023 (UTC)

How does hobby glue work?
I want to use a certain brand of adhesive for a task. It is sold as a general purpose hobby glue supposedly able to stick just about anything. The packaging says it is a mix of acetone 45% (average), ethyl acetate 20% (average), and n-butyl acetate 5% (average). This adds up to only 70% - the packaging does not say what the missing 30% is. The distributor provides a Material Safety Data Sheet - it just says the balance is determined to be non-hazardous and doesn't say what the balance is.

Question: Given the listed ingredients are all solvent liquids, what is the balance likely to be?

This adhesive upon exposure to air changes from a low viscosity clear colourless liquid to a soft rubbery translucent material within a few minutes, then gradually goes quite hard over several days whether air exposure continues or not. There is very little shrinkage. Question: What is the result of the chemical reaction(s) triggered by exposure to air - what is the chemical name or chemical formula for the cured state?

I rang the distributor but they don't know anything - they have no chemists. They buy it ready made and packaged from somebody else who in turn buys it from somebody else who in turn buys the ingredients in large quantities and mixes and packages it in accordance with some recipe that was devised decades ago - in other words they have no idea how it works. Dionne Court (talk) 14:22, 1 August 2023 (UTC)
 * Maybe rubber cement? From the description you've given, that sounds like it.  -- Jayron 32 14:26, 1 August 2023 (UTC)
 * It is nothing like rubber cement. It is colourless and eventually sets hard. Dionne Court (talk) 16:49, 1 August 2023 (UTC)
 * Many adhesives contain cyanoacrylate as a main ingredient and other ingredients to make it dry faster or be less bumpy or make it less liquidy. Acetates are hardeners, often used in nail polish. They would give the hardened glue a smoother surface. Acetone is a solvent. It is often used to keep mixtures from hardening. When exposed to air, the acetone quickly evaporates, leaving the hardened glue behind. If cyanoacrylate is the main ingredient, you would see the glue harden to a clear and smooth blob as the acetone evaporated and then the cyanoacryalte would harden white as it reacted with moisture in the air. It would be far more helpful is you mentioned the name of the product because there are many alternatives to cyanoacrylate. 12.116.29.106 (talk) 16:04, 1 August 2023 (UTC)
 * I would be surprised if it was cyanoacrylate (sold as "Superglue") as it forms a very strong bond on most surfaces, regardless of whether they are smooth or rough. One thing it won't bond to is skin, which cyanoacrylate will.  Also, it has been sold since I was child, and that was >70 years ago.  It is called "Tarzan's Grip" but I assume that is a locally branded name.  I expect similar formula glues have various brands/names around the world.   Note:  the same company also sells cyanoacrylate adhesive, which is very considerably more expensive. Dionne Court (talk) 17:06, 1 August 2023 (UTC)
 * Anything like this? H&S datasheet here. Martin of Sheffield (talk) 17:22, 1 August 2023 (UTC)
 * This MSDS for "Tarzan's Grip All Purpose Glue" says it contains polyurethane. -- Jayron 32 17:29, 1 August 2023 (UTC)
 * See also List of polyurethane applications. -- Jayron 32 17:34, 1 August 2023 (UTC)
 * Another option is polyvinyl acetate, which is a super common general purpose glue ingredient. In the U.S. most of the Elmer's glue varieties are PVA-based adhesives.  -- Jayron 32 17:36, 1 August 2023 (UTC)
 * The averages of the proportions of acetone, ethyl acetate, and n-butyl acetate all match up, this checks out. Card Zero  (talk) 21:14, 1 August 2023 (UTC)
 * Thanks Jayron.  I had downloaded a much more recent MSDS than the one you found - it looks like the later one omitted the polyurethane for some reason - I assume by error.  It didn't occur to me to try getting another version of the MSDS.
 * It would not be PVA as it is waterproof.  PVA definitely is not.   Dionne Court (talk) 03:40, 2 August 2023 (UTC)
 * No, definitely not Goy Gum. `Dionne Court (talk) 03:27, 2 August 2023 (UTC)
 * Swedish inventor Axel Karlson around 1922 made one of the first synthetic glues by dissolving Celluloid in Acetone. The resulting quick-drying glass-clear Karlsons Univarsalklister (universal glue) is still sold in northern Europe with swedish advertising slogans such as the pointed "Alla använder Karlsons klister utom jag, för jag är en åsna" (Everyone uses Karlson's glue except me because I'm an ass) and the unofficial "Om ditt hjärta nånsin brister, laga det med Karlsons klister" (If your heart should break asunder, make it whole with Karlson's wonder). The same or a similar glue is widely marketed by German manufacturer UHU. I suggest that a homemade version can be made by dissolving pieces of PMMA (Polymethyl methacrylate i.e. thermoplastic acrylic glass such as Plexiglas or Perspex) in acetone. Philvoids (talk) 14:42, 2 August 2023 (UTC)
 * One should be careful not to use Karlsons klister as a clyster. DuncanHill (talk) 23:02, 2 August 2023 (UTC)