1. Shear force
Tensile shear strength, the tensile shear strength test of adhesives is often carried out under high or low temperature conditions. It is the main bonding strength index of adhesives.
① Apply tensile shear load to the adhesive layer of the bonded joint test piece, until the maximum load of the joint is broken, divided by the value of the bonding area.
② That is, under the load parallel to the adhesive layer, when the bonded specimen is broken, the shear force per unit bonding surface is expressed in MPa.

2. Glass transition temperature
Glass transition is the transition between the glass state and the high elastic state of amorphous polymer materials. With the glass transition temperature as the boundary, polymer polymers show different physical properties: below the glass transition temperature, polymer materials behave like plastics; above the glass transition temperature, polymer materials behave like rubber.