The world of chemistry has revolutionized the concept of adhesive and glue in all trades, including the sector of violin making. Until the early 1900s, animal bone glue by bone (strong) or by tissue (weak) was used, so the classical lutherie of the 1600s could only adopt this type of solution.
The animal glue has no excellent properties, since it is an organic glue its use is to be limited to some works. In violin making, it is recommended to use in certain types of restorations, especially when you do not want to mix two different compounds (an organic glue may not react well with another synthetic one). It is a reversible glue, it is cleaned with water and it melts with little heat. It is therefore necessary to be very careful with instruments glued with this type of glue, summer heat can cause the adhesion to come off. The animal bone glue or bag tissue, prepared at home, can mold up after 2 days, should be kept in the fridge, but its strong odor does not allow it. One of the best products on the market, ready to use and that does not spoil off the fridge is the Titebond hide glue.
The glues that are subsequent to the animal glue are the vinyl glues (polyvinyl acetate, Vinavil), rubbery glues of little use in our work. They are mainly used to glue chipboard or veneer. They have a good resistance to water and heat, but being rubbery they are not easy to work with. Not to be used in classical violin making, while in the electric one they can find some applications. If you need to use it other than violin making, buy it, because it is a glue that resists moisture (from outside).
Aliphatic glues (Titebond original and similar) are the American solution to the problem. They solve the weaknesses of animal glue, having a strength and elasticity equal to a vinyl, but retain the characteristics of reversibility. They are cleaned in water and melt (slowly) with water and heat, but a greater heat, which we will not find easily in the environment. So you can rest easy, without exaggerating. I remember using aliphatics on guitar bridges, which were then unstuck for leaving the instrument in the car in the sun. Available in three dispenser.
The polyurethane glue, is in the Titebond version (which I know) an exceptional glue, but with targeted and considered uses. It is not easily found and since it comes from America it is often found a glue already hardened and with a very short expiry date. It is a glue that inflates and attaches to everything it finds, adhering to almost all types of materials (not just porous, wood type). I recommend the use in operations made in economics and unlikely, for example pasting a broken pallet into a thousand parts (of which 50% are absent) of a tool of little value. Swelling can fill like a stucco. Be careful to close the cap well!
I advise you not to exaggerate in ordering large quantities, the glues dry up with time, even when they are closed they harden. Especially polyurethane.