Strength
The strength of the adhesion between two materials depends on which of the above mechanisms occur between the two materials, and the surface area over which the two materials contact. Materials that wet against each other tend to have a larger contact area than those that do not. Wetting depends on the surface energy of the materials.
Low surface energy materials such as polyethylene, polypropylene, polytetrafluoroethylene and polyoxymethylene are difficult to bond without special surface preparation.
Read more about this topic: Adhesion
Famous quotes containing the word strength:
“For my people lending their strength to the years: to the gone
years and the now years and the maybe years, washing ironing cooking scrubbing sewing mending hoeing plowing digging planting pruning patching dragging along never gaining never reaping never knowing and never understanding;”
—Margaret Abigail Walker (b. 1915)
“Adolescents swing from euphoric self-confidence and a kind of narcissistic strength in which they feel invulnerable and even immortal, to despair, self-emptiness, self-deprecation. At the same time they seem to see an emerging self that is unique and wonderful, they suffer an intense envy which tears narcissism into shreds, and makes other people’s qualities hit them like an attack of lasers.”
—Terri Apter (20th century)
“One reason writers write is out of revenge. Life hurts; certain ideas and experiences hurt; one wants to clarify, to set out illuminations, to replay the old bad scenes and get the Treppenworte said—the words one didn’t have the strength or ripeness to say when those words were necessary for one’s dignity or survival.”
—Cynthia Ozick (b. 1928)