Unclassified 



SECURITY CLASSIFICATION OF THIS PAGEfWTi.n Data Entered) 



20. Continued 



of wood and short lengths of cotton and hemp rope exposed for comparison. Similarly, 

 natural rubber covers of samples of insulated electrical cable deteriorated during the 

 2-1/2 years, but plastic and synthetic rubber covers of other insulated cables underwent 

 no visible deterioration. 



Library Card 



Civil Engineering Laboratory 



DURABILITY OF PLASTICS IN ANAEROBIC MARINE 



SEDIMENTS (Final), by J, S. Muraoka and H. P. Vind 



TN-1402 14 p. illus October 1975 Unclassified 



1. Material deterioration 2. Marine environment I. YF54. 543.007.01.001 



Specimens of a wide variety of plastic sheets, ropes, and electrical cable insulations were 

 partially buried in anaerobic harbor sediments to determine the effect of hydrogen sulfide on 

 polymeric materials. For comparison, specimens of the same materials were exposed in aerobic 

 surface %vaters. After 2-1/2 years, the specimens were all recovered. Very little change was noted 

 in the appearance, strength, or hardness of any of the specimens of synthetic polymeric materials. 

 In contrast, nothing remained of samples of wood and short lengths of cotton and hemp rope 

 exposed for comparison. Similarly, natural rubber covers of samples of insulated electrical cable 

 deteriorated during the 2-1/2 years, but plastic and synthetic rubber covers of other insulated 

 cables underwent no visible deterioration. 



L 



Unclassified 



