| Glue 3 | |
|
Figure:
Amino acids in collagen and other proteins. |
Other proteins,
such as casein and albumin, have properties that make them able to form
glues in similar ways, however they are more brittle and therefore less
effective at bending to fit the shape of the adherend.
This new hide glue with collagen as the main component of the adhesive, not only applies to the science behind extracting glue from animals, but also the science behind how adhesives work. The most widely accepted theory of the science behind adhesives is the Wettability-abosorbtion theory, which states that the adhesive must come in complete intimate contact (completely wet the adherend) to be most effective. The adhesive's strength is maximized when intermolecular forces like London Dispersion forces, dipole-dipole, dipole-induced dipole, or electrostatic forces are involved in the attraction of the adhesive to adherend. The adhesive can also share a chemical bond to the adherend, though most hide glues consist of attractions from intermolecular forces. For a glue to work and be a proper adhesive, it at some point has to be a liquid and at some point has to transform to a tough, non-liquid substance. In hide glue, which is a porous substance, these characteristics are carried out as the collagen adhesive is mixed with a water solvent, which then evaporates to form a hard, strong substance consisting of the reformed collagen glue. Note:
A disease in cattle, dermatosporaxis, causes bone collagen not to mature. If symptoms such as fragile bones, clear or blue sclera, or
loose ligaments can be detected, the animal’s glue will not make
a strong adhesive. |
