and butanol (14 ml.) were added, refluxed for 15 minutes, butanol (30 ml.) 

 was added and refluxing was continued until a clear solution was obtained 

 (approximately 24 hours). Water and butanol were removed by distilla- 

 tion and fresh butanol was added to the pot to keep the volume constant. 

 After 470 ml. had distilled, the contents of the pot were anhydrous. 

 Films formed from this product by evaporation of the solvent and heat- 

 ing were not water resistant. 



Experiment 7 . Dimethylol urea (12 g.) and formalin (16.3 g.) were 

 mixed in a 125 ml. Erlenneyer flask. Sodium hydroxide solution (10%) 

 was added to make the mixture alkaline. On heating, a solution formed, 

 melamine (8.4 g.) was added, and heating was again continued until a 

 solution formed. The solution was set aside to cool. A quantity of 

 the cool solution was applied to filter paper and heated. The friable 

 film bubble which formed was essentially unaffected by boiling water. 



CONCLUSIONS 



1. From the results of the literature survey and laboratory 

 experimentation, it is concluded that none of the materials produced by 

 crosslinking or complexing would be suitable for forming water-insoluble 

 resins in-situ in a porous material. None had properties equal or 

 superior to precipitated polyvinyl alcohol. 



2. Precipitated polyvinyl alcohol shows promise as a waterproofing 

 agent for porous construction materials. 



FUTURE PLANS 



No further search for water- insoluble resins, formed by chemical 

 crosslinking or complexing of water-soluble compounds, is planned. 



