6.5 Polymers in the War Times
During times of war (1937–1945), international interactions were seriously
interrupted. Advancement of basic science and technology was, however, encouraged
by the government and supported by society as well. Major scientific contributions,
mostly disclosed after World War II, are as follows:
• 1937: San-ichiro Mizushima et al. proposed the rotational isomeric state model
for internal bond rotation [9].
• 1939: Ichiro Sakurada, Sungi Lee et al. announced the invention of polyvinyl
alcohol (PVA) fiber [8, 10]. A test pilot plant for the commercial production of
“Vinylon” was built in 1946.
• 1940: Sakurada derived an equation for polymer viscosity (the original article
has been reproduced in English: cf. ref [11]) independently from the Mark–
Houwink formula:
η sp =c
À
Á
c!0
¼ KP
n
ð1Þ
where P stands for the degree of polymerization. The relation is often called
Mark–Houwink–Sakurada equation.
• 1941: Establishment of the Japanese Research Association for Synthetic Fibers
to promote collaboration between government, industry, and academia. The
association was later renamed the Federation of Polymer Chemistry.
• 1942: Syoten Oka derived a formula [12] for the end-to-end distance of polymer
chains having independent rotational potential:
< r
2
> =nl
2
¼ 1 þ cos θ
ð
Þ = 1 À cos θ
ð
Þ
½
1 þ cos ϕ
ð
Þ = 1 À cos ϕ
ð
Þ
½
ð 2Þ
with θ and ϕ respectively representing the bond angle and bond rotation angle.
• 1943–1947: Ryogo Kubo published a series of papers on the statistical theory of
rubberlike substances, and wrote a book [13].
• 1944: The Federation of Polymer Chemistry published the first issue of the
journal (in Japanese) named Kobunshi-Kagaku (High Polymer Chemistry).
• 1944: Balloon bombs, the first intercontinental weapon, were made out of
Japanese paper (long fibers from local trees) coated (pasted) with Konnyaku
mannan (jelly made from devil’s-tongue starch). The balloon (diameter ~10 m,
weight ~200 kg) was inflated with a given amount of hydrogen so that they rose
to a height where they could be carried by the jet stream to the west coast of
America. Toshio Hata left a note stating that a group of polymer chemists from
Tokyo Institute of Technology was involved in various aspects of this project,
mainly as technical advisers. Several hundred balloons (out of ~9,000) reached
the west coast of the USA (Oregon). The number of casualties caused by this
“high tech” weapon was, however, said to be minor [14].
148
A. Abe
During times of war (1937–1945), international interactions were seriously
interrupted. Advancement of basic science and technology was, however, encouraged
by the government and supported by society as well. Major scientific contributions,
mostly disclosed after World War II, are as follows:
• 1937: San-ichiro Mizushima et al. proposed the rotational isomeric state model
for internal bond rotation [9].
• 1939: Ichiro Sakurada, Sungi Lee et al. announced the invention of polyvinyl
alcohol (PVA) fiber [8, 10]. A test pilot plant for the commercial production of
“Vinylon” was built in 1946.
• 1940: Sakurada derived an equation for polymer viscosity (the original article
has been reproduced in English: cf. ref [11]) independently from the Mark–
Houwink formula:
η sp =c
À
Á
c!0
¼ KP
n
ð1Þ
where P stands for the degree of polymerization. The relation is often called
Mark–Houwink–Sakurada equation.
• 1941: Establishment of the Japanese Research Association for Synthetic Fibers
to promote collaboration between government, industry, and academia. The
association was later renamed the Federation of Polymer Chemistry.
• 1942: Syoten Oka derived a formula [12] for the end-to-end distance of polymer
chains having independent rotational potential:
< r
2
> =nl
2
¼ 1 þ cos θ
ð
Þ = 1 À cos θ
ð
Þ
½
1 þ cos ϕ
ð
Þ = 1 À cos ϕ
ð
Þ
½
ð 2Þ
with θ and ϕ respectively representing the bond angle and bond rotation angle.
• 1943–1947: Ryogo Kubo published a series of papers on the statistical theory of
rubberlike substances, and wrote a book [13].
• 1944: The Federation of Polymer Chemistry published the first issue of the
journal (in Japanese) named Kobunshi-Kagaku (High Polymer Chemistry).
• 1944: Balloon bombs, the first intercontinental weapon, were made out of
Japanese paper (long fibers from local trees) coated (pasted) with Konnyaku
mannan (jelly made from devil’s-tongue starch). The balloon (diameter ~10 m,
weight ~200 kg) was inflated with a given amount of hydrogen so that they rose
to a height where they could be carried by the jet stream to the west coast of
America. Toshio Hata left a note stating that a group of polymer chemists from
Tokyo Institute of Technology was involved in various aspects of this project,
mainly as technical advisers. Several hundred balloons (out of ~9,000) reached
the west coast of the USA (Oregon). The number of casualties caused by this
“high tech” weapon was, however, said to be minor [14].
148
A. Abe