Samuel Dwight Gehman (December 7, 1903 – June 1, 1992) was a Goodyear physicist noted for development of a modulus-based measurement of rubber's

glass transition temperature The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rub ...

Personal

Gehman was born on December 7, 1903. He died in

Akron, Ohio Akron () is a city in Summit County, Ohio, United States, and its county seat. It is the List of municipalities in Ohio, fifth-most populous city in Ohio, with a population of 190,469 at the 2020 United States census, 2020 census. The Akron metr ...

, on June 1, 1992.

Education

In 1922, he was one of eight sophomores selected for honors at the

University of Pennsylvania The University of Pennsylvania (Penn or UPenn) is a Private university, private Ivy League research university in Philadelphia, Pennsylvania, United States. One of nine colonial colleges, it was chartered in 1755 through the efforts of f ...

. He completed his doctoral dissertation in 1929 on the topic ''Reflection of Soft X-rays''.

Career

Gehman was recruited to Goodyear by Ray P. Dinsmore. He made influential studies of

strain crystallization Strain crystallization 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, as well as other elastomers and polymers. ...

via

x-rays An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...

, of rubber's dynamic properties, and of

heat transfer Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, ...

in rubber. He managed physics research at Goodyear's research division and was renowned for developing the Gehman low-temperature twist test, which gave laboratories convenient and precise low-temperature stiffening measurements of rubber compounds. He was an inventor of approximately 70 patents. In 1972, Gehman was listed at 10th out of the 100 top contributors to the world's rubber literature published between 1932 and 1970. Gehman retired in 1968 following 40 years with Goodyear Tire & Rubber Co.

Awards and recognitions

*1965 - Fellow of the

American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of ...

* 1970 -

Charles Goodyear Medal The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society#Organization, American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, ...

from the ACS Rubber Division

External links

Audio interview
with Samuel D. Gehman

References

Polymer scientists and engineers 1903 births 1992 deaths Tire industry people Goodyear Tire and Rubber Company people {{US-physicist-stub