TEOS-PDMS-Calcium Oxalate Hydrophobic Nanocomposite for Protection and Stone Consolidation

Round 1

Reviewer 1 Report

The topic of the manuscript is original and interesting, because the possibility to have both protection and consolidation in a single treatment in conservation of cultural heritage, in particular in protection of calcareous stones, is very appealing. The argument is well explained, the experimental and theoretical methods are clearly described and the interpretations of the results are plausible.  

Just some editorial errors should be corrected and some clarification and explanations should be introduced by the authors:

• In the Abstract, there is an unclear sentence, without the verb, probably a misprint: “The hydrolysis of TEOS, as well as the formation of CaOx thermogravimetric analysis (TG/DTA)”.
• In Section 2 and in Section 3 there is a reference in square brackets ([1]): it’s not clear what it refers to.
• The numbering of the figures and their reference in the text must be revised: Figure 6 is missing and consequently the others are numbered incorrectly. Furthermore, Figure 3 is numbered as Fig.1 and Figure 5 as Fig.2. Finally, on page 6, the reference to Figure 4B should be indicated as 4ii(b).
• The reference mentioned at the bottom of page 2 is indicated with the DOI but the related article is not present in the bibliography: why?

• The work focuses on a particular type of stone, that is limestones. The description of these 'alfas' stones (‘Alfas Stone’?) is referred to the bibliography, but it is not clear whether it is a single lithotype or several (similar but not identical) lithotypes.
• Moreover, the tests were done on 3 different stone groups, which apparently differ in shape and size. However, the reason for this choice is not clear: different sizes for different tests? Other? Is the lithotype the same or are there also petrographic differences between the different groups?
• And the results, how are they related to the different groups? FT-IR spectra, Color measurements results and UPV tests results on treated stone are unique: this would suggest that these are average values ​​on all the specimens, of all 3 groups. Water absorption tests, on the other hand, have been reported for the 3 different groups of specimens, and are different for the untreated materials: the curves of groups 1 and 2 are very similar, but the curve for group 3 is very different. Why? What explanation did the authors give themselves for this? This aspect should be analyzed and better explained, because if the 3 groups of specimens show differences in behavior, the other data (color, UPV, and FT-IR) will have to be revised in the light of this.

After taking care of clarifying these aspects of the manuscript, the paper could be accepted for the publication.

Author Response

Thank your contribution. Attached you can find our responses. 

Author Response File: Author Response.pdf

Reviewer 2 Report

Please see the file in attach. 

Comments for author File: Comments.pdf

Author Response

Thank you for your remarks. Attached you can find our responses.

Author Response File: Author Response.pdf