DETERIORATION OF ORGANIC POLYMERS 



1079 



Fig. 1 — Cellulose ester telephone housings. 



A— Acetate after 7 cycles of high and low humidity. 



B — Original. 



C — Butyrate after 7 cycles of high and low humidity. 



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Fig. 2 — Neoprene ear pad after one year's use, at left, and original at right. 



Fig. 3— Samples of rubber in various stages of weathering. 



