THE DEGRADABILITY OF NATURAL RUBBER
( TOY BALLOONS )
A bibliographical review of the scientific literature showing the
degradability of toy balloons, which are made of natural rubber, due
to the effects of bacteria, light, air, and weathering.
D. K. Burchette
The Environmental Committee of the
National Association of Balloon Artists
May 22, 1990
- Reference 1. Brace Golding, Ph. D.; Polymers and Resins;
van Nostrand Publishing; New York; 1959; Page 162:
- "(Natural) Rubber is extremely sensitive to decomposition
by the action of oxygen, particularly in the presence of light."
- Reference 2. W. J. Roff and J. R. Scott; Fibers, Films,
Plastics and Rubbers; Butterworths; London; 1971:
- "The relatively high protein content of natural rubber
(2-3.5%) renders it liable to attack by micro-organisms, even when
vulcanized... Vulcanized rubbers deteriorate with passage of time
due to oxidation and chain scission in the molecular network." Pg.
"The chemically unsaturated structure of natural rubber renders
it liable to oxidation, with consequent deterioration... This occurs
in all forms of the material on long keeping in air, and is
aggravated by sunlight." Pg. 327.
- Reference 3. C. M. Blow; Rubber Technology and
Manufacture; Butterworths; London; 1971; Pg. 36:
- "Familiar to all is the liability of rubber to perish, to
harden and crack or soften to a sticky residue. Natural rubber is
particularly sensitive to this respect..."
- Reference 4. Anthony Davis; Weathering of
Polymers; Applied Science Publishers; London; 1983; Pg. 240:
- "The inherent reactivity of the unsaturated groups in diene
rubbers (natural rubber) makes them particularly prone to oxidative
degradation. Thus in the presence of air... light can cause rapid
deterioration. It has also been known for many years that diene
rubber (natural rubber) is subject to attack by ozone even at the
low concentrations found outdoors."
- Reference 5. C. C. Davis; The Chemistry and Technology
of Rubbers; ACS Monograph Series; Reinhold; New York; 1937; Pg.
- "The gradual perishing of soft vulcanized rubber is
universally recognized. This deterioration eventually causes
vulcanized rubber compounds to become hard, brittle, or soft and
sticky and easily torn... Oxidation and the action of light are
important factors in hastening the deterioration."
- Reference 6. Harry L. Fisher; Chemistry of Natural and
Synthetic Rubbers; Reinhold; New York; 1957; Pg. 49:
- "Deterioration of natural rubber... is caused chiefly by
action of oxygen and ozone. Light tends to activate these reactions,
but oxygen and ozone attack these rubbers even in the dark"
- Reference 7. P. K. Freakley, A. R. Payne; Theory and
Practice of Engineering With Rubber; Applied Science Publishers
LTD; London; 1978; Pg. 12:
- "(Natural) Rubber, like many other organic materials is
liable to undergo changes with time. The main cause is oxidation by
atmospheric oxygen, which may be aggravated by light..."
- Reference 8. R. D. Deanin Ph. D.; Polymer Structure,
Properties, and Applications; Cahners Books; Boston; 1972;
- "The unsaturated double bond in natural rubber.., causes
sensitivity to oxygen and ozone (especially when stretched), and
this sensitivity is increased by light producing rather poor aging
- Reference 9. The Language of Rubber; E. I. DuPont
de Nemours & Co.; Wilmington, Delaware; 1957; Pg. 42:
- "Exposure of (natural) rubber compositions to weathering
and sunlight accelerates the rate at which their physical properties
deteriorate... much more rapid in the presence of sunlight. The
primary effects noted are attributable to ozone attack and