28.10 Nanomaterials 1205
Exercise 28.16
a.Write the formula for the heat transferred in the isothermal elongation of an ideal rubber.
b.For an ideal rubber that contains 1.00× 10 −^6 mole of cross-linked polymer chains, find the
value ofqandwfor stretching it to 3.00 times its original length at 298.15 K.PROBLEMS
Section 28.9: Rubber Elasticity
28.44a.Write a general expression forCf−CL, the
difference between the heat capacity at constantfand
that at constantL, for rubber.
b.Write the expression for part a for ideal rubber.RichardP. F e ynman(1918–1988) wasa
professor of theoretical physicsat the
CaliforniaInstitute of Technology. He
workedonthe ManhattanProjectduring
WorldWarII,andwas the co-recipient
of the 1965 Nobel Prize inphysics for
his work onquantum electrodynamics.
Hebecame oneofthebest-known
scientists of his time.
28.10 Nanomaterials
In 1959 Richard Feynman gave a talk entitled “There’s Plenty of Room at the Bottom,”
in which he discussed the possibility of writing the entireEncyclopedia Britannicaon
the head of a pin.^45 He offered to give a prize of $1000 of his own money to anyone who
could reduce the size of a printed page by a linear factor of 1/25000, and anticipated
the scanning electron microscope to read such an image. He also offered to give a prize
of $1000 to anyone who could build a functioning electric motor that would fit into a
cube 1/64 of an inch on a side. This prize was claimed within a few years, but the first
prize was apparently not claimed before Feynman’s death in 1988.GerdBinnig,1947–,andHeinrich
Rohrer,1933–,were employedat the
IBMResearch Laboratory inZurich
whenthey inventedtheSTM. They
sharedhalf of the 1986 Nobel Prize in
physics for their invention.
The modern era of nanotechnology probably began with two developments:
(1) the invention of the scanning tunneling microscope (STM) by Binnig and Rohrer
in 1981,^46 and (2) the creation of “buckyballs” in 1985.^47 The STM provides the
ability to read the miniaturized page envisioned by Feynman in 1959. Various web-
sites give the history of the STM.^48 This device involves ceramic piezo-electric sub-
stances that can move a molecularly sharp stylus over a solid surface by molecular
distances while measuring the height of features on the surface by the amount of
current that flows through the stylus. It was the first device that produced images of
individual atoms.
RichardE.Smalley,1943–2005,was
professor of chemistry,physics,and
astronomyatRice University. He
receivedthe 1996 Nobel Prize in
chemistry for his work onnanomaterials.
Smalley and his coworkers irradiated graphite with intense laser beams. This created
C 60 molecules that are balls of 60 carbon atoms arranged in 20 hexagons and 12
pentagons, with bonds in a pattern like the seams on a soccer ball. The equilib-
rium conformation of a buckyball corresponds to a point group called the icosahedral
group, containing numerous rotations and reflections. There are now also buckyballs of
different sizes, and “nanotubes” that are cylindrical analogues of buckyballs. Multi-
walled carbon nanotubes have been found in a 400-year old dagger made of Damascus
steel.^49(^45) R. P. Feynman,Science and Engineering, California Institute of Technology, 1960.
(^46) See for example http://www.ifs.tu-darmstadt.de/fileadmin/phil/nano/baird-shew.pdf, which shows the
famous IBM logo created with 35 xenon atoms.
(^47) Buckminsterfullerene is named after Buckminster Fuller, a famous architect who incorporated geodesic
domes into many of his building designs.
(^48) A. S. Duwez,Nature Nanotechnology, 1 , 22 (2006); S. Katanoet al.,Science, 316 , 1883 (2007).
(^49) P. Paufler,Nature, 440 , 286 (2006).