JAIC 1997, Volume 36, Number 2, Article 4 (pp. 143 to 150)
JAIC online
Journal of the American Institute for Conservation
JAIC 1997, Volume 36, Number 2, Article 4 (pp. 143 to 150)

A NEW TECHNIQUE FOR DETERMINING THE DEPTH OF PENETRATION OF CONSOLIDANTS INTO LIMESTONE USING IODINE VAPOR

RAKESH KUMAR, & WILLIAM S. GINELL



2 MATERIALS


2.1 CONSOLIDANTS

The following solutions, emulsions, and dispersions were tested as consolidants in varying concentrations:

  1. Rhoplex AC-33: acrylic emulsion in water
  2. Rhoplex AC-630: acrylic emulsion in water
  3. El Rey Superior 200: acrylic emulsion in water
  4. Carboset 514-H (acrylic copolymer dispersion) + ERL-4221 (3,4-epoxy cyclohexyl methyl-3,4-epoxy cyclohexyl carboxylate): acrylic-epoxy solution in isopropanol/water
  5. Eponex 1510 (hydrogenated bisphenol-A-epichlorohydrin) + Jeffamine T403 (polyoxypropylenetriamine): epoxy in isopropanol
  6. Bayhydrol 121: polyurethane dispersion in water
  7. Acryloid B-72: acrylic polymer in toluene
  8. Conservare SS-OH: tetra ethoxy silane in 2-butanone and 2-propanone
  9. Conservare SS-H: tetra ethoxy silane & alkoxysilane in 2-butanone and 2-propanone
  10. Polyvinyl acetate (AYAF): polyvinyl acetate in toluene


2.2 STONE

Indiana and Xunantunich limestones were used for this study. Indiana limestone is a beige-colored, homogeneous, fossiliferous limestone. Chemically and mineralogically it is almost pure calcite with a small amount of quartz, hematite, and magnesium. The porosity of this limestone is ∼18.6 %.

The Xunantunich (Belize) limestone is of marine origin and is inhomogeneous. Chemically and mineralogically it is a fine-grained, almost pure, calcite with minor amounts of magnesium, iron, aluminum, and silica impurities (<2%). The hardness varies with the distribution of soft and hard calcite. The porosity of this type of stone, as measured by mercury intrusion porosimetry, varies from 26 to 56%.


2.3 IODINE VAPOR

Iodine vapor was generated by room temperature sublimation of solid iodine in a closed glass chamber.

Solid iodine and iodine vapor are hazardous materials and should be handled with care and in accord with Materials Safety Data Sheet (MSDS) recommendations.


Copyright 1997 American Institute for Conservation of Historic and Artistic Works