Development of a surface-specific, anti-weathering stone preservative treatment

Conference · Tue Apr 01 04:00:00 EST 1997

OSTI ID:471402

Rao, S M; Brinkar, C J ^[1]; Rao, S M; Ross, T J ^[2]

---

1. Sandia National Lab., Albuquerque, NM (United States)
2. Univ. of New Mexico, Albuquerque, NM (United States); and others

We are testing an anti-weathering preservation strategy that is specific to limestone surfaces. The strategy involves the application of a mineral-specific, bifunctional, passivating/coupling agent that binds to both the limestone surface and to the consolidating inorganic polymer matrix. The sol-gel based reactions form composite materials with desirable conservation and anti-weathering properties. We present the results of our efforts, the highlights of which are: (1) scanning probe microscopy of moisture-free calcite crystals treated with the trisilanol form of silylalkylaminocarboxylate (SAAC), reveals porous agglomerates that offer no significant resistance to the mild leaching action of deionized water. When the crystals are further consolidated with a silica-based consolidant (A2**), no dissolution is seen although the positive role of the passivant molecule is not yet delineated. (2) Modulus of rupture tests on limestone cores treated with an aminoalkylsilane (AEAPS) and A2** showed a 25-35% increase in strength compared to the untreated samples. (3) Environmental scanning electron microscopy of treated limestone subjected to a concentrated acid attack showed degradation of the surface except in areas where thick layers of the consolidant were deposited.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 471402
• Report Number(s): SAND--97-0787C; CONF-970680--1; ON: DE97004440
• Country of Publication: United States
• Language: English

Related Subjects

29 ENERGY PLANNING, POLICY, AND ECONOMY
36 MATERIALS SCIENCE
CORROSION RESISTANCE
EVALUATION
LIMESTONE
MATERIALS TESTING
PERFORMANCE
PRESERVATIVES
SURFACE TREATMENTS
WEATHERING