Table 2. Special Variations of Basic Formulations by 

 Changing Part B'^ 



Formulation 



Number 



Part B^ 

 (by weight) 



(by weight) 



DMP-30^ 

 (by weight) 



Biocide 

 (by weight) 



101-2 



12 



6 







102-2 



12 



6 







101-5 



8 





5 





102-5 



8 





5 





101-19 



16 







5 



102-19 



16 







5 



Weights shown in table were used with 100 parts of Part A of 

 either 101 or 102. 



Part B of 101 and 102 are identical. 



Ancamine LO of Anchor Chemical Company. 



2, 4, 6-Tri (dimethylaminomethyl) phenol. 



Reaction product of tributyltin oxide and fatty acids of 

 linseed oil. 



LABORATORY TESTING 



A laboratory procedure was developed for determining the bonding 

 strength of underwater -applied coatings to steel. A small, 1/8-inch- 

 thick steel panel is sandblasted to white metal .^ It is then placed in a 

 tank of seawater and brush-coated with an underwater-applied coating. 

 After curing underwater for 1 week, the coated panel is dried and lightly 

 sanded. One or more steel probes are then bonded to the sanded coating 

 using a high-strength, quick-setting adhesive. After the adhesive has 

 cured overnight, the probe is pulled from the panel using a table model 

 Instron testing machine. 



The bonding strengths of the six formulations in Table 2, which 

 were applied and cured at the various temperatures indicated, are listed 

 in Table 3. It can be seen from this table that: 



(1) The 101-19 formulations were the easiest to apply. 



(2) Of the three sets of curing conditions, application and curing 

 at 70°F generally resulted in the greatest bonding strength, and 

 application and curing at 40°F generally resulted in the weakest. 



Steel Structures Painting Council Surface Preparation No. 5. 



