Aggregation and Protection by fluorinated elastomers of stone exposed to the atmospherics agents

Fluorinated elastomers have been tested as aggregating and protective materials for stone exposed to the open air. These compound may in fact be expected to have a good resistance to pollutants and irradiation, to retain their elasticity even once applied in very thin layer and be capable to aggregate loose material. We have choosen hexafluoropropene-vinylidene fluoride copolimers (1/4 ratio) having 65-67% fluoride content and molecular wheight in the 100,000- 400,000 range. After testing for stability to thermal shock, prelonged U.V. irradiation and solubility we have chosen as material to be tested on the stone a copolimer having 65% fluorine and 360,000 average molecular wheight. A 2,5% acetone solution of the above copolimer was used to treat Pietra di Vicenza (Biosparite) and Pietra di Lecce (Biocalcarenite) by capillary absorption. The results obtained show interesting aggregation and protective properties even when the elastomer is used in amounts which allow these stone to breath.