The Meaning of "Creep" of Rubber Products

Manufacturer: We just received a complaint from one of our customers stating that one of our rubber products has shown excessive "creep" property. What is this? We would appreciate your usual good explanation.

John Woon (Senior Latex Consultant): Very simple. "Creep" has a lot to do with "Stress Relaxation". Most people are familiar with the latter but not the former.

Stress relaxation of a vulcanised rubber refers to the loss in stress when the rubber is held at constant strain (e.g. at a given elongation), over a period of time. Closely related to stress relaxation is "Strain Relaxation".

Strain relaxation of a rubber product refers to the gradual increase in deformation (e.g. elongation) under constant load, over a period of time.

"Creep" is another term for "Strain Relaxation". I suggest you review your curative recipe and try to use an EV (efficient vulcanisation) system as far as possible.