ABSTRACT
ABSTRACT: This work focuses on the characterization of organic resin bound mortars, used in reproductions of sculptural and ornamental stone exposed outdoor. Here, specimens were prepared from two commonly used organic binders in the ambit of Culture Heritage Conservation/Restoration, specifically the epoxy resin Araldite ® Sintolit LY554 and the polyester resin Tritone ® (CTS). In order to imitate the original stone lithotype, natural aggregates have been added to the different binders by crushing the marble Macael, the Tosca Rocafort limestone, the Bateig Novelda calcarenite and the Niñerola alabaster. Similarly, mortar test specimens were prepared with three different additives: a UV inhibitor (Tinuvin B75 from BASF), HALS (Tinuvin 292 Kremer) and a biocide (Biotin R CTS) in order to improve their properties against UV irradiation and biodeterioration. All prepared mortar specimens were subjected to accelerated aging tests by irradiation with ultraviolet light for 1080 h in order to assess its color variation. Color change has been determined using a Minolta CM-2600d colorimeter. The results indicate a high resistance of the polyester resin mixed with Sintolit Tritone ® (Tosca Rocafort, Bateig Novelda as well as Niñerola alabaster), with barely perceptible variations. The worst values have been registered for those made solely with epoxy resin, with very high variations. Similarly, the mortars made with the marble aggregate Macael with both resins did not give satisfactory results, with differences varying between CIEL*a*b* 30 and 40 units.
