jFabr1c
The physical and chemical properties needed in a balloon material
are: (l) chemical stability, (2) low permeability, (3) high tensile
atrengtb, (4) low brittle temperature, (5) high tear resistance,
(6) high transparency to heat radiation and (7) light weight.
In Table 1 the properies of 7 plastics and 2 coated materials are
given. From this data polyethylene and saran appear to be the most
sui table films.
Table l
!Low Temper- 1 Penne- : Tensile . Tear Re-i Ease of' I Stability to
~ture Prop-· ability 1 Strength i sistance 1 Fabrioa- 1Ultraviolet
. erties l · tion 1
I 'I
!Goodi Low!Polyethylene Good ' Medium IGood 1 Good
I i l
! High I
!Saran Fair I Low jPoor Fair IFair
rylcm l High
I
I
!GoodGood Low jLow Good
I
i IGoodIGoodfinylite Very poor Medium 1 Medium Good
I
l
!Good
!
~Teflon Believed Low I High I Cannot i Good
good •,
I
I ·be fabri-j
kthocellu- [
IFair
ce.ted iI
Good Very Low Good !Good
high IIlose
!Fair IGoodPlio film Poor High Poor Poor
!Nylon or sill '
fabric ooa tee
~ith:
Neoprene Fair Low High Fair Fair Fair
Butyl Good Low High Fair Fair Good
rubber
Having decided upon the proper fabric to be used, an effort was
made to interest a number or companies in the fabrication and
production of balloons. The first supplier or balloon• ..d. or
·polyethylene was Harold A. Smith, Inc., lfame.roneck, lrew York.
In these balloons, 4 and 8 mil sheets were heat sealed to to~
a spherical cell open at the bottom. Load attachment tabs were
set into the fabric and loading lines ran from these taba to a
load ring. This method of' supporting the load proved to be un-
sa ti sfac tory.
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