Strain crystallization

Crystallization

Crystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas. Crystallization is also a chemical solid–liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid...

is a phenomenon in which an initially amorphous solid material undergoes a phase transformation due to the application of strain. Strain crystallization occurs in natural rubber, and some other elastomer

Elastomer

An elastomer is a polymer with the property of viscoelasticity , generally having notably low Young's modulus and high yield strain compared with other materials. The term, which is derived from elastic polymer, is often used interchangeably with the term rubber, although the latter is preferred...

s. The phenomenon has important effects on strength and fatigue properties. There are various techniques for measuring crystallization in rubber, including: x-ray diffraction, specific heat changes, and density changes.

Sources

• Chapter 1, Engineering with Rubber, Ed. A. N. Gent, Hanser, 1992. ISBN 3-446-17010-3.
• B. Huneau, STRAIN-INDUCED CRYSTALLIZATION OF NATURAL RUBBER: A REVIEW OF X-RAY DIFFRACTION INVESTIGATIONS, Rubber Chem. Technol. 84, 425 (2011); doi:10.5254/1.3601131