Evening star., 1942-05-16
Of Sturs, Men
And Atoms
Notebook Of Science Progress
In Laboratory, Field
And Study
By Thomas r. Henrv.

SS SASoy
By Thomas r. Henry.
Both Government and industrial ex.
perts are confused over the rubber sit
| uation.
Few more complex situations ever have
troubled q people. The problems, in
every case intricate, are agricultural, BIZ
illogical, chemical, economic and engi-
neering. but the solutions of all must be
meshed together.
For nearly a quarter Of century the
chief. almost the only. source of rubber
has been the hevea tree Of the East In
dies. From this source natural rubber
could be laid down at American ports
for about IL cents pound, with good
profit for everybody concerned.
That source, however, probably is gone
for at least 10 years. If the japanese
are forced to give up their present con-
quests. there is a strong probability that
they will kill the plantations; and it will
require at least seven years to restore
them.
Meanwhile, there are four sources from
which the loss can be made up. First
and apparently by far the most signih-
cant is synthetic rubber. The cheapest
and most practical kind, 1t generally is
agreed at present, although some would
argue otherwise. is Buna S. originally a
German product, the chief constituent
OF which in this country is one OF the
hitherto waste gases from petroleum.
Plants already in operation can pro-
duce about 200 900 tons year and those
expected to be in operation within the
next year or two probably can turn out
close to a million tons. The cost will be
about 20 cents a pound. little less than
double that Of natural rubber. Other
types Of rubber for special purposes, such
as resistance to Oil and sunlight, are be-
ing produced. They are too expensive
for tires and, for the most part, not we'll
suited to them.
With the Buna production now EaI-
ing good headway. the United States
should have close to its normal supply Of
rubber. such as it is. in year or so.
That does not mean that there will be
plenty available for civilian use The
enormous requirements Of the Army and
Navy must be met. Without knowing
the volume of these, any predictions con-
corning tires are futile.
Buna S. as it happens, is far from
ideal for tires. Its friction is low. Cars
driven on tires made of it would be in
constant danger of skidding. The Ger
mans, after long experimentation, over
came this in part by mixing 1t with nat
ural rubber. Perhaps they since have
improved the synthetic rubber itself
The mixture in the United States today
would have to be with reclaimed rubber
Synthetic rubber can be made in many
ways. Hardly day passes that some
body does not present Government ex-
perts with a supposedly new idea. When
this is attended with publicity there is
much public confusion. Some of the
ideas now advanced as new are so years
old. Others are not economically feas-
ible. There is no trickier problem in all
chemistry. say synthetic rubber experts
All such suggestions now received by
the Government are considered confiden-
tial and cannot be discussed even in
their broader outlines
| Rubber. 1t seems, could be made OF al
most any plant-at cost ranging be-
tween so cents and 81 900 pound.
Almost daily Government Depart
ments get suggestions for new sources.
The most promising is the Mexican
shrub, guayule, on which extensive ex-
periments now are in progress. 1t is pos
sible that eventually it will yield l5-cent
rubber
About four years are required before
guayule plantation can be harvested
profitably. The rubber obtained from
the plant is about as good as that from
East Indian trees
At present there is shortage of plant
ing material. If all the seeds available
were planted Immediately, they would
yield. according to a recent estimate by
the Tariff Commission, about 5000 tons
of rubber in 1914. If harvested in 1916,
they would yield about % 900 tons.
Experiments now are in progress to
improve guayule. They are kept mil
itary secrets.
A good source, for year or so, is re-
claimed rubber. About 100000 tons
could be reclaimed from the 194l supply
more than half the normal civilian re-
quirement. The rubber is somewhat in
ferior to the new product and must be
mixed with natural rubber for service
able tires. Obviously henceforth there
will be very little available to be re-
claimed. Motorists will patch their tires
until there is no rubber left in them.
With each retaining the quality of the
! rubber is considerably reduced.
|
The native land of the hevea tree was
| Northern South America
Many have asked why Brazilian rub
ber cannot be resurrected. The answer
is that up to the present the trees cam
not be grown in plantations in South
America. 1t was due to no dark and deep
British and Dutch plot that the world
center of rubber culture was shifted to
| the East Indies.
When planted close together in South