Durability Improvement of Cement Using Amphiphilic Calcium Carbonate Nanoparticles
Round 1
Reviewer 1 Report
Please carefully read the comments listed below and “fully” address them:
1- The ABSTRACT is not written in a logical order. Start with an overview of the topic and a rationale for your paper. Describe the methodology you used and the general outline of the manuscript. Also, in the end, state the result in more detail (i.e., provide some numbers). And, since your work is relatively novel, I strongly recommend you create graphical abstract for your manuscript. A graphical abstract is a single, concise, pictorial, and visual summary of the main findings of the article. It could either be the concluding figure from the article or better still a figure that is specially designed for the purpose, which captures the content of the article for readers at a single glance.
2- “In application, the main indexes of durability consist of permeability, freeze-thaw resistance, and tolerance to hard environments”. This is a good intro but not complete. In fact, apart from freeze-thaw cracking, “alkali-silica reaction” and “unsoundness” are other cement durability issues, which should be referred to in your manuscript. For this reason, please read and reference the following two landmark manuscripts from Thomas and Hooton’s research labs.
Alkali-Silica Reaction
· Li, Z., Thomas, R. J., & Peethamparan, S. (2019). Alkali-silica reactivity of alkali-activated concrete subjected to ASTM C 1293 and 1567 alkali-silica reactivity tests. Cement and Concrete Research, 123, 105796.
· Li, Z., Thomas, R. J., Lezama, D., & Peethamparan, S. (2017). Evaluation of ASTM Methods for Detection of Alkali-Silica Reaction in Alkali-Activated Concrete (No. 17-04375).
Soundness
· Kabir, H., & Hooton, R. D. (2020). Evaluating soundness of concrete containing shrinkage-compensating MgO admixtures. Construction and Building Materials, 253, 119141.
· Kabir, H., Hooton, R. D., & Popoff, N. J. (2020). Evaluation of cement soundness using the ASTM C151 autoclave expansion test. Cement and Concrete Research, 136, 106159.
3- Detail on the purity of the ordered lauric methacrylate and methyl polyethylene glycol methacrylate. Explain any other related sample preparation.
4- The dispersion procedure of AmphCC, which is detailed in section 2.2 is unique… did the authors come up with this procedure, or is it coming from the existing literature (in this case please provide the reference)? And what was the purpose of selecting a hydrophobic substrate, i.e., calcium carbonate?
5- What was the step size and dwell time of your XRD setup? Also, could you detail the accelerating voltage and beam current of your SEM setup?
6- How many samples were tested for XRD analysis and could you provide the error bar (envelope) if there is any?
7- Fig. 4 shows the water absorption test results, which are valuable. Could you do the Contact Angle test on the treated substrates and report the results? (choose 4 microliter of drop volume and dispense it using a syringe or pipette)
8- In Figs. 4 and 5 report the error bars as well.
9- Conclusion: Can authors highlight future research directions and recommendations? Also, highlight the assumptions and limitations (e.g., 1-2 shortcoming(s) of the present study)? Besides, recheck your manuscript and polish it for grammatical mistakes (you can use “Grammarly to quickly edit your document).
Author Response
Point 1: The ABSTRACT is not written in a logical order. Start with an overview of the topic and a rationale for your paper. Describe the methodology you used and the general outline of the manuscript. Also, in the end, state the result in more detail (i.e., provide some numbers). And, since your work is relatively novel, I strongly recommend you create graphical abstract for your manuscript. A graphical abstract is a single, concise, pictorial, and visual summary of the main findings of the article. It could either be the concluding figure from the article or better still a figure that is specially designed for the purpose, which captures the content of the article for readers at a single glance.
Response 1: Thanks for the reviewer's kind suggestions, the Abstract has been rewritten.
Point 2: “In application, the main indexes of durability consist of permeability, freeze-thaw resistance, and tolerance to hard environments”. This is a good intro but not complete. In fact, apart from freeze-thaw cracking, “alkali-silica reaction” and “unsoundness” are other cement durability issues, which should be referred to in your manuscript. For this reason, please read and reference the following two landmark manuscripts from Thomas and Hooton’s research labs.
Alkali-Silica Reaction
- Li, Z., Thomas, R. J., & Peethamparan, S. (2019). Alkali-silica reactivity of alkali-activated concrete subjected to ASTM C 1293 and 1567 alkali-silica reactivity tests. Cement and Concrete Research, 123, 105796.
- Li, Z., Thomas, R. J., Lezama, D., & Peethamparan, S. (2017). Evaluation of ASTM Methods for Detection of Alkali-Silica Reaction in Alkali-Activated Concrete (No. 17-04375).
Soundness
- Kabir, H., & Hooton, R. D. (2020). Evaluating soundness of concrete containing shrinkage-compensating MgO admixtures. Construction and Building Materials, 253, 119141.
- Kabir, H., Hooton, R. D., & Popoff, N. J. (2020). Evaluation of cement soundness using the ASTM C151 autoclave expansion test. Cement and Concrete Research, 136, 106159.
Response 2: The refernences have been supplemented. Introduction section has also been revised.
Point 3: Detail on the purity of the ordered lauric methacrylate and methyl polyethylene glycol methacrylate. Explain any other related sample preparation.
Response 3: The preparation section has been revised, with purity grade of the reagents specified.
Point 4: The dispersion procedure of AmphCC, which is detailed in section 2.2 is unique… did the authors come up with this procedure, or is it coming from the existing literature (in this case please provide the reference)? And what was the purpose of selecting a hydrophobic substrate, i.e., calcium carbonate?
Response 4: More details about the preparation of AmphCChas been supplemented as Supporting Information. Hydrophobic calcium carbonate was used for its wide use in paints and fillers, hence its resonable cost and easy access. hydrophilic CC was not used due to its insufficient stability in nano-form in water (by solution-recrystallization, and form millimeter-scale particles), which is the main reason for common hydrophobicizing treatment in manufacturing. Besides, the oileic acid on HbCC may contribute to microstructure hydrophobicizing.
The dispersion procedure is based on typical processing procedures of hydrophobic powders (treatment with a modifier in a hydrophobic solvent), but the dispersant is novel.
The dispersant is inspired by polycarboxylate, with the hydrophilic backbone fully replaced by hydrophobic esters. The dispersant was selected over tranditional surfactants (e.g. sodium dodecyl sulfonate) due to its non-ionic and polymeric nature, which regulates its air-entraining power (undisred considering the dosage). Also, the esters on the backbone can grdually hydrolyze and release laurinol, which can hydrophobicize microstructures and contributed to permeation resistance improvement .
Relevant descrption and discussion has been revised to specify the point. Comparison between the amphiphilic dispersant and other common dispersants has also been conducted in the revised manuscript
Point 5: What was the step size and dwell time of your XRD setup? Also, could you detail the accelerating voltage and beam current of your SEM setup?
Response 5: The details on XRD and SEM characterizations have been specified
Point 6: How many samples were tested for XRD analysis and could you provide the error bar (envelope) if there is any?
Response 6: For qualitative analyses, samples were scanned for once, For quantitative analyses, three parallels were conducted.
Point 7: Fig. 4 shows the water absorption test results, which are valuable. Could you do the Contact Angle test on the treated substrates and report the results? (choose 4 microliter of drop volume and dispense it using a syringe or pipette)
Response 7: Contact Angle tests has been conducted on 14d and 28d paste samples. Relevant procedures, data and discussions are available in the revised manuscript.
Point 8: In Figs. 4 and 5 report the error bars as well.
Response 8: Error bars in relevant Figures have been supplemented. Other figures and tables has also been revised if error bars are appliable.
Point 8: Conclusion: Can authors highlight future research directions and recommendations? Also, highlight the assumptions and limitations (e.g., 1-2 shortcoming(s) of the present study)? Besides, recheck your manuscript and polish it for grammatical mistakes (you can use “Grammarly to quickly edit your document).
Response 8: The conclusion has been revised with perspecitve on highlights and shortcomings
Reviewer 2 Report
The purpose of the study is to demonstrate an efficiency of a new dispersant for dispersion of CaCO3 nanoparticles for the use in cement. Known-in-the-art is a number of methods for dispersion of CaCO3 nanoparticles for this application (refer, for example, to: Kawashima, S., Seo, J. W. T., Corr, D., Hersam, M. C., & Shah, S. P. (2014). Dispersion of CaCO3 nanoparticles by sonication and surfactant treatment for application in fly ash–cement systems. Materials and Structures, 47(6), 1011-1023. https://doi.org/10.1617/s11527-013-0110-9).
The authors of the manuscript should, first of all, analyze the state-of-the-art and give arguments regarding a choice of new dispersant and, following the results obtained in the study, compare its efficiency with other dispersants.
The comparison of the results obtained with the new dispersant with those obtained without dispersants has no sense, because the use of nanoparticles without preliminary dispersion is not applied in practice. For the above reasons, it is not possible to evaluate scientific importance and practical applicability.
Author Response
Point 1: The authors of the manuscript should, first of all, analyze the state-of-the-art and give arguments regarding a choice of new dispersant and, following the results obtained in the study, compare its efficiency with other dispersants.
Response 1: The Introduction section has been revised with more specified presentation of state-of-art and more references. The abstract was also revised to highlight the purpose of this work. Comparison with other dispersants was conducted, with work supplemented in Section 2.3 and 3.1
Point 2: The comparison of the results obtained with the new dispersant with those obtained without dispersants has no sense, because the use of nanoparticles without preliminary dispersion is not applied in practice. For the above reasons, it is not possible to evaluate scientific importance and practical applicability.
Response 2: A comparison with other common dispersant, namely ionic polycarboxylate, sodium dodecyl sulfonate and alkylphehol polyethylene oxide, has been conducted in the revised manuscript. The experiemntal methods and results are supplemented in Section 2.3 and 3.1, respectively. According to the results, the amphiphilic dispersant (AmphD), showed advantage over ionic polycarboxylate and small-molecule surfactants. The advantage is due to its amphiphilic, non-ionic and polymeric structure.
Round 2
Reviewer 1 Report
The authors addressed my comments and the manuscript can be published in the present format.
Reviewer 2 Report
All recommendations have been made. The article can be recommended for publication.
