Repairability is a measure of the capability of a material to have 

 punctures and tears patched in the field: a function of the ease with 

 which the adhesive is used, the time required for the bond to set up, 

 and the strength developed by the bond. All of the materials in Table 4 

 can be repaired with an adhesive, solvent -welded, or heat-sealed. Since 

 data were not available to permit comparison between coatings this 

 property was not included in Table 4. 



While nearly all fabrics listed claim to have resistance to rot and 

 mildew, and some were indicated as meeting related MIL SPECS, no measure 

 of this property was provided to allow comparison. Some coated fabrics 

 are inherently resistant to attack by microorganisms, whereas others are 

 specially formulated to resist attack. Also, prevention of marine 

 growth can be accomplished by including antifouling compounds in the 

 coating formulation. The desirability of this is questionable since 

 these compounds work by leaching from the coating into the water and may 

 themselves cause a pollution problem. Work currently being conducted at 

 the Naval Ship Research and Development Center with antifouling coatings 

 having reduced pollution potential may have future beneficial application 

 for oil spill containment booms [31]. 



All listed materials claimed to be flame-resistant, and all possessed 

 acceptable colorability. 



All fabrics for which data were available seemed to satisfactorily 

 resist the absorption of water as indicated by the high hydrostatic 

 resistance. The Hypalon/neoprene /nylon composite showed the highest, 

 and the chlorinated polyethylene the lowest, hydrostatic resistance. 



The low temperature characteristics of all the materials was satisfac- 

 tory, but sufficient data were not available to compare high temperature 

 characteristics . 



Although abrasion resistance data were available on most materials, 

 the type of tests and manner of reporting the data were not uniform. 

 Only those indicating abrasion resistance in terms of the Wyzenbeck 

 method using 80-grit garnet paper for 2,000 cycles and expressing 

 results in terms of breaking strength were included in Table 4. It 

 should be noted that, while no comparison data are presented, the litera- 

 ture indicates that the abrasion resistance of polyurethane to be approxi- 

 mately eight times better than that of other plastic coatings [23]. 



Adhesion, as mentioned earlier, is inversely related to tear 

 strength for a given fabric. The data presented in Table 4 express 

 adhesion capacity in pounds determined in accordance with FTMS 191 

 Method 5970. To avoid conflicting statements, no quantitative value has 

 been established in the boom specification for adhesion. Rather, the 

 specifications require an 80% retention in adhesive capacity after a 

 fresh water immersion test. Therefore, no comparison of the listed 

 material can be made in terms of this property. 



The only fabric listed in Table 4 for which data are available that 

 meets the tear strength requirement of 200 pounds is the Shelter Rite 

 7128 (PVC /polyester). 



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