UV-Curable Fluorocarbon Polyurethane Coatings for Marble Kitchen Countertops
Round 1
Reviewer 1 Report (Previous Reviewer 3)
I have read the manuscript provided by the authors, and even though I like their approach to using this material as household coatings, they have to improve their manuscript. Points need clarification, and references should be added. Overall, I like the manuscript's structure; the results seem promising. Please see the pdf attached for all the comments
Comments for author File: 
Comments.pdf
Author Response
Question 1. Lines 25-30: Please rephrase it to make it more appealing
Response：Thank you for your valuable advice. I have rephrased these sentences to make it more appealing.
Question 2. Lines 42-44: I think the authors should give some examples of the other materials used in such applications
Response：Thank you for your valuable advice. I have added some examples of the other materials used in such applications, like 2K PU coatings and silicone stone protectors.
Question 3. 2.1: Please add purities
Response：Thank you for your valuable advice. I have added purities for each material.
Question 4. 2.2: If authors have used other works for this synthesis, please add references
Response：Thank you for your valuable advice. I have added reference for this synthesis.
Question 5. Figure 1: How sure are the authors that when the reaction starts does not react the TEOH in both ends of HDI? What is the yield of the final product in both reactions?
Response：Thank you for your valuable advice. I added these sentences to make it clear as “TEOH-6 was added to HDI titrimetrically at constant pressure, and from the reaction kinetics, a small amount of TEOH-6-HDI-TEOH-6 was present during the synthesis of HDI-TEOH-6, especially late in the reaction when the HDI concentration decreased, which was not able to react with HEA in next step reaction. When the UV-cured fluorocarbon polyurethane coatings were subjected to UV irradiation, a small amount of TEOH-6-HDI-TEOH-6 still existed in the coating film, which did not affect the coating film performance and fluorocarbon chain content, and did not affect the hydrophobic and oleophobic properties of the film.’
Question 6. 2.3: Same as comment 4
Response：Thank you for your valuable advice. I have added reference for this coating formulation.
Question 7. Lines 126-127: Based on what? Please be more specific and add references
Response：Thank you for your valuable advice. I have added judgment criteria and references.
Question 8. What is exactly the role of Hydrofluoric ether to the formulations? Please explain more and a scheme to show what happens will help
Response：Thank you for your valuable advice. I drew graphs showing the effect of solvent volatilization on fluorocarbon chain migration for different formulations
Question 9. Lines 136-147: I think here is repetitively. Please correct it
Response：Thank you for your valuable advice. I have deleted one paragraph and made changes to the other.
Question 10. Figure 3a: I think the authors should show in the figures the bands they are refer to. Also, add references for the different bands. I have pointed out the bands they are refer to in the figure.
Response：Thank you for your valuable advice.
Question 11. Figure 4b: What is the peak found at 3.7 ppm?
Response：Thank you for your valuable advice. I have given interpretation in the article that these peaks at 1.65 ppm and 3.65 ppm are from the solvent DMF and do not affect the judgement of the structure of the UV-cured monomer.
Question 12. Figure 5: As in comment 10, please show where are the bands that disappear
Response：Thank you for your valuable advice. I have marked where -NCO disappears and C=C appears in the figure.
Question 13. Lines 297-299: Please add references
Response：Thank you for your valuable advice. I have added reference for these sentences.
Question 14. Lines 304-306: Please add references
Response：Thank you for your valuable advice. I have added reference for these sentences.
Question 15. Lines 328-331: I am not sure about the statement of the authors. I agree that the more F atoms on the surface the most hydrophobic this coating should be. But, as it can be seen from the figure the area of F is not bigger for F3 than F4. F3 starts at around 17500 counts and the top is at 27500. On the other hand F4 for example starts at 12500 to 40000. So how F3 has bigger area? As authors said, the chemical structures are the same for all coatings; I think they should show the percentages of all elements that participate (C, O, F…) and there the higher percentage of F will be seen.
Response：Thank you for your valuable advice. In fact, the values I calculated in origin, the integral area of F3 is larger than F4, and I have marked the exact values in the article. Since the total weight of each formulation is the same and the ratio of C H N O is the same, the size of the integral area of F can be considered as the amount of fluorine content on the surface of the paint film. I add that note in the article.
Question 16. Lines 338-342: Please add references
Response：Thank you for your valuable advice. I have added references for these lines.
Question 17. Figure 10: The photo of b, looks a little bit strange.
Response：Thank you for your valuable advice. I exported the image from the software of contact angle tester. This may be a problem with the glass of the slide, but it does not affect the contact angle measurement.
Question 18. Lines 375-378: Please add references
Response：Thank you for your valuable advice. I have added references for these lines.
Question 19. Figure 11: I am not so sure if the authors can show the roughness of the samples only from SEM images. Roughness can be measured from AFM, where it is directly correlated with surface that is measured. This point must be corrected or AFM roughness values must be presented.
Response：Thank you for your valuable advice. I admit that AFM is a good means to test the roughness of the coating film. For some reason, I wasn't able to find a suitable AFM instrument to test roughness in a short time. In addition, this article focuses on the effect of fluorocarbon side chains on hydrophobicity and oleophobicity of the coating film. SEM could give a reference roughness test, which does not affect the presentation of the article topic.
Question 20. Lines 421-424 & 452-456. Authors are using the same explanation for the decrease in hydrophobicity after acid and base treatment, but they use different references. Is this correct？
Response：Thank you for your valuable advice. These explanations can be found in many articles. For the sake of clarity of expression, I cite the same references for two places in the article.
Reviewer 2 Report (Previous Reviewer 1)
thank you very much I am very happy for this work it is excellent it is good I think it is well written and no fault thank you
thank you very much I am very happy for this work it is excellent it is good I think it is well written and no fault thank you
Author Response
Thanks
Reviewer 3 Report (New Reviewer)
The paper under consideration deals with coatings based on UV-curable fluorocarbon polyurethane resin and intended as cover solution for kitchen countertop. The topic appears to be a merely industrially oriented research aimed to overcome technological issues both for consumers and producers. Nevertheless, taking into account the scientific approach of the authors, the work is well organized with worth of experimentals. The reference list provides a satisfactory overview of the field and abstract and conclusion sections well describe aims and findings. Despite that few points have to be more seriously worked making this version not suitable for publication. The authors aim their work toward hydrophobicity and oleophobicity, but if the results could be slightly acceptable for water with contact angle measurements around the hydrophobicity, it is not understandable the oleophobic part involving cetane with very low contact angle values. Moreover the work should require an investigation on roughness and not least the hysteresis of contact angle is only mentioned in references, but, unfortunately not studied. Also a surface energy study could be a preliminary test to understand the this work still requires more efforts and consistent data.
English quality is acceptable
Author Response
Question 1. it is not understandable the oleophobic part involving cetane with very low contact angle values.
Response：Thank you for your valuable advice. Due to the high non-polarity of cetane, the contact angle will be much lower than the corresponding water contact angle even on oleophobic surfaces.
Question 2. Moreover the work should require an investigation on roughness and not least the hysteresis of contact angle is only mentioned in references
Response：Thank you for your valuable advice. In the article, the microstructure of the coating film was characterized by using SEM, and the roughness of the coating film was demonstrated.
Question 3. Also a surface energy study could be a preliminary test to understand the this work still requires more efforts and consistent data.
Response：Thank you for your valuable advice. There is a correspondence between surface energy and contact angle, and the measurement of contact angle is more convenient and intuitive. This paper is biased towards applied research to develop suitable formulations, so the contact angle is used as the object of study.
Reviewer 4 Report (New Reviewer)
The article seems very complete. The authors performed the necessary characterization for the practical application of the material. I only have some minimal observations that I consider necessary before the article is published.
1. In the stain resistance tests (Figure 15) it is clearly observed in all cases that the coating is damaged after the attack. For the investigation to be complete, I think it is necessary for the authors to show what happens after the attack.
2. If the coating has certain advantages over other coatings that have been formulated in the past, I think it is necessary to highlight the advantages and disadvantages (if any).
3. The conclusions are very general. I consider necessary to highlight the characteristics of the materials that gave the best results.
Author Response
Question 1. In the stain resistance tests (Figure 15) it is clearly observed in all cases that the coating is damaged after the attack. For the investigation to be complete, I think it is necessary for the authors to show what happens after the attack.
Response：Thank you for your valuable advice. There are comparisons in the figure, for example a vs a’, showing what happens after the attack.
Question 2. If the coating has certain advantages over other coatings that have been formulated in the past, I think it is necessary to highlight the advantages and disadvantages (if any).
Response：Thank you for your valuable advice. I will highlight the benefits of UV-curing fluorocarbon polyurethane coatings at the summary.
Question 3. The conclusions are very general. I consider necessary to highlight the characteristics of the materials that gave the best results.
Response：Thank you for your valuable advice. In the article, the microstructure of the coating film was characterized by using SEM, and the roughness of the coating film was demonstrated. I've made some additional notes on the conclusions section.
Round 2
Reviewer 1 Report (Previous Reviewer 3)
I have read the revised manuscript from the authors. I have to say that the manuscript has improved a lot. Based on my previous report, I still have two points that the authors probably need to work on a little.
Comment 17: The photo in Figure 11b needs to be corrected. It appears that the contact angle is in a slide. The authors should add another image.
Comment 19: I agree with the authors about the AFM and SEM, but you cannot show the certainty of roughness from SEM. Authors should rephrase this point and write more like a hypothesis since SEM does not give you values, just images.
Author Response
Thank you for your encouragement. As for the two comment you mentioned, I gave the following reply.
Comment 17: The photo in Figure 11b needs to be corrected. It appears that the contact angle is in a slide. The authors should add another image.
Response: Thank you for your valuable advice. I have added another image to replace the original one.
Comment 19: I agree with the authors about the AFM and SEM, but you cannot show the certainty of roughness from SEM. Authors should rephrase this point and write more like a hypothesis since SEM does not give you values, just images.
Response: Thank you for your valuable advice. I totally agree that SEM photos just a picture, not an exact number. To be more objective and serious, I reorganize the text and make hypothetical conclusions using SEM photos as references.
Reviewer 3 Report (New Reviewer)
The revised version of the manuscript under consideration appears not improved. The authors didn't take into account the reviewer' suggestions adding new experimental activities in order to give a suitable shape to the work. The paper cannot be published. The authors have to take into account to spend more time with a more serious approach to the suggested scientific methodology.
English is sufficient
Author Response
Regarding the reviewer 3's comments, I have a few comment:
Firstly, the contact angle of cetane in the article is actually not low, the contact angle of ordinary coating film surfaces is only more than ten degrees, while the contact angle of cetane in this paper can be about 50 degrees, which is not easy to achieve.
Secondly, I was asked to use the surface energy to study the hydrophobicity and oleophobicity of the coating film., but most of paper about hydrophobic oleophobic paper is to use the contact angle as the judgment standard, because the surface energy and contact angle have a corresponding relationship, and contact angle data is more easily understood by the reader. In addition, the surface energy data cannot distinguish hydrophobicity and oleophobicity well.
Thirdly, as for contact angle lag, in fact, this paper focuses on the easy cleaning performance of UV-curing fluorocarbon polyurethane coating for marble countertops. Simulating the kitchen environment, it is more meaningful to test the static contact angle of water and cetane, and to test the contact angle after abrasion and acid and alkali immersion, as well as the easy cleaning of common kitchen materials on countertops. It is not necessary to study the contact angle lag, because the contact angle lag do not simulate the kitchen environment and do not correlate the hydrophobic and oleophobic, easy cleaning performance very well, though it doubles the amount of article data.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
This interesting manuscript deals with the Preparation and performance of UV-curable fluorocarbon 2 polyurethane coatings for kitchen marble countertopsA lot of derived physicochemical properties were calculated and interpreted . The subject is importante from practical and theoretical points of view owing the high used in several applications. In my opinion the manuscript could be accepted after checking the following points:
1. A deep checking of English language is strongly recommended because there are several grammar mistakes that makes the reading very hard.
2. The manuscript title is not clear and I recommend to reduce it to mention the curable fluorocarbon 2 without other words to avoid confusions.
3. specify and indicate the name of each parameter F1 ,F2, F3 ,F4, …F9 on the title of the table.
Comments for author File: 
Comments.docx
Author Response
Question 1：A deep checking of English language is strongly recommended because there are several grammar mistakes that makes the reading very hard.
Response：Thank you for your valuable advice. English language has been polished.
Question 2：The manuscript title is not clear and I recommend to reduce it to mention the curable fluorocarbon 2 without other words to avoid confusions.
Response：Thank you for your valuable advice. The article title has been revised to “UV-curable fluorocarbon polyurethane coatings for kitchen marble countertops”.
Question 3：specify and indicate the name of each parameter F1, F2, F3, F4, …F9 on the title of the table.
Response：Thank you for your valuable advice. The table title has been specified with each parameter F1, F2, F3, etc.
Reviewer 2 Report
The paper from Xi and Yuan reports on the synthesis and characterization of UV-curable fluorocarbon polyurethane coatings for kitchen marble countertops. The topic is somehow well-known and well reported in the literature, therefore the novelty of the manuscript is rather limited. Therefore, rejection is suggested
Further comments and suggestions are listed as follows:
- the Introduction is too qualitative. It is nonsense to say that somebody did something without highlighting some quantitative results. Besides, the novelty (if any) of the proposed manuscript should be better evidenced
- the radiation intensity (mW/cm2) on the sample surface should be measured. The power of a lamp is not meaningful
- the glass transition temperature of the prepared coatings should be determined
- the completeness of the UV-curing reaction should be assessed. To this aim, FTIR spectroscopy could help a lot
- dynamic contact angle measurements should be performed, hence measuring the advancing and receding contact angle values and calculating the hysteresis, which is directly related to the surface roughness of the coatings
- the contact angle measurements should also be performed on both sides of the films, i.e. that exposed to air and that in contact with the substrate
- XPS measurements should be used for determining the F/C ratios. Different take-off angles should be employed for the analyses. This way, it could be possible to assess the possible presence of F concentration gradients
- from an overall point of view, the Results and Discussion is plenty of results, but lacks their critical interpretation and justification
- The overall english needs some improvements
Author Response
Question 1：the Introduction is too qualitative. It is nonsense to say that somebody did something without highlighting some quantitative results. Besides, the novelty (if any) of the proposed manuscript should be better evidenced
Response：Thank you for your valuable advice. This paper discusses the implementation of hydrophobic and oleophobic of kitchen marble countertops, which is not a completely new topic, but the solution offered in this paper is a completely new solution. The methodology of other teams is presented to compare the innovation of the different solution, and not simply to compare the data.
Question 2：the radiation intensity (mW/cm2) on the sample surface should be measured. The power of a lamp is not meaningful
Response：Thank you for your valuable advice. It is not only the intensity of the light radiation that determines the conditions for curing or not curing a UV-curable coating. Firstly，the absorption peak of the photo-initiator in the coating matches the wavelength of the light source. Secondly the quantity of free radicals in the coating can be increased by adjusting the distance from the light source and the radiation time. Lastly, the addition of photo-initiator in these coatings are sufficient to complete the curing of the coating.
Question 3：the glass transition temperature of the prepared coatings should be determined
- the completeness of the UV-curing reaction should be assessed. To this aim, FTIR spectroscopy could help a lot
Response：Thank you for your valuable advice. As a highly cross-linked coating, the finished paint film is insoluble and fusible and no longer has the glass transition temperature of a thermoplastic resin.
Question 4：dynamic contact angle measurements should be performed, hence measuring the advancing and receding contact angle values and calculating the hysteresis, which is directly related to the surface roughness of the coatings
Response：Thank you for your valuable advice. From a practical application scenario, where the kitchen marble countertop is always horizontal. Dynamic contact angle, forward and backward contact angle tests are not necessary, otherwise the length of the article would have to be more than doubled.
Question 5：the contact angle measurements should also be performed on both sides of the films, i.e. that exposed to air and that in contact with the substrate
Response：Thank you for your valuable advice. The side of the paint film in contact with the marble will never be applied and there is no necessary to testing data from this side. The fluorocarbon chain segments in the paint film will also migrate to the side of the film that is in contact with air, so the focus is on assessing the surface of the paint film.
Question 6：XPS measurements should be used for determining the F/C ratios. Different take-off angles should be employed for the analyses. This way, it could be possible to assess the possible presence of F concentration gradients
Response：Thank you for your valuable advice. The amount of C in the paint formulation is much greater than the amount of F, and due to measurement errors, the F/C in each formulation may be very close. The F content of the paint film surface is tested in the article only to further verify that the formulation F3 has relatively better hydrophobic and oleophobic properties than the others, as it can be concluded from the amount of HEA-HDI-TEOH-6 added to the formulation, and also from the water and cetane contact angles of the paint film surface.
Question 7：from an overall point of view, the Results and Discussion is plenty of results, but lacks their critical interpretation and justification
Response：Thank you for your valuable advice. I have added some more clarifications. Each table and figure are followed by a specific description, analysis and interpretation. The conclusion of the article also contains a summary of the entire text.
Question 8：The overall English needs some improvements
Response：Thank you for your valuable advice. The overall English has been improved.
Reviewer 3 Report
I have read the manuscript provided by the authors, and I have to say that it is an interesting work. I like that they are using their material in real applications. Some points can be improved and also some questions to be answered. The authors should also provide references to some of their statements. Please see the pdf attached with all the comments.
Comments for author File: Comments.pdf
Author Response
Question 1：Line 9: I think the term “living contamination” is not adequate, please rephrase.
Response：Thank you for your valuable advice. I have changed “living contamination” to “food ingredient contamination”.
Question 2：Line 15: Please define HFE, before using it.
Response：Thank you for your valuable advice. Hydrofluoric ether has been defined to HFE in abstract.
Question 3：Lines 20-23: I think this last part does not fit the abstract in terms of presenting explanation about the results. I propose to remove it, since I can imagine it is explained in results.
Response：Thank you for your valuable advice. I have removed the last part in abstract.
Question 4：Line 24: I think hydrophobic and oleophobic should be two separate keywords.
Response：Thank you for your valuable advice. I have separated hydrophobic and oleophobic to two independent keywords.
Question 5：Lines 70-72: This statement needs references.
Response：Thank you for your valuable advice. I have added reference [55-59] for these lines.
Question 6：2.1: Please add purities.
Response：Thank you for your valuable advice. I have added purities for each material.
Question 7：2.2, line 112-113: Authors state that “Then the stirring and nitrogen gas was stopped to obtain 38%-42% solid fluoro carbon branched UV-curable monomer”. With that, they want to indicate that around 60% is only HDI-TEOH? How do they proceed on separate one component from the other? If they have used a synthetic protocol from another manuscript it should be added.
Response：Thank you for your valuable advice. I have indicated “58-62% is XYL solvent” in the paper.
Question 8：Table 1: Why authors have F1-F4 and F6? Where is F5?
Response：Thank you for your valuable advice. I have corrected F6 to F5 in table.
Question 9： Lines 127-134: I understand why the authors wanted to show here why the exclude some formulations, but showing here results is a little bit out of the scope of 2.3. I think they have to rephrase that.
Response：Thank you for your valuable advice. I have rephased these lines.
Question 10：2.4: I think a scheme or figure will help the reader to follow better the procedure.
Response：Thank you for your valuable advice. I have used a figure to make the process clearer.
Question 11：3.1: Authors should add references for these characteristic peaks. Moreover, where are located the -F- bands? There are also manuscripts where they can be found these values.
Response：Thank you for your valuable advice. I have added reference [60] for these lines. The absorption peak at 1400-1000 cm-1 is a fluorocarbon bond characteristic absorption indicated in the paper.
Question 12：Figure 2: I think the figure should be rearranged. Zooms should be done in specific areas of the spectra, where the authors focus the differences. In addition, the characteristic bands should be marked on the figure.
Response：Thank you for your valuable advice. I have rearranged the figure. Zooms have been done, and the characteristic bands have been marked on the figure.
Question 13：References should be added for the NMR as well.
Response：Thank you for your valuable advice. I have added reference [61] for these lines.
Question 14：Figure 3: What are the peaks found in both spectra at 1.65 ppm and 3.65. Also in Figure 3 CHCl3 should be marked as CDCl3, since it is a deuterated solvent.
Response：Thank you for your valuable advice. Spectra at 1.65 ppm and 3.65 were caused by Tetrahydrofuran. Maybe it was from uncleaned NMR tubes. CDCl3 has been marked on the figure.
Question 15：Line 263: Authors state, “so the cross-link density of the coating film will decrease”. How do they know that? Maybe to add references in the explanations here.
Response：In the formulation, I replaced the active monomer Trimethylolpropane triacrylate (TMPTA), which has three double bonds, with the fluorinated monomer HEA-HDI-TEOH-6, which has only one double bond, so the crosslinking density was reduced.
Question 16： Lines 264-266: Please add references.
Response：Thank you for your valuable advice. Please refer to Question 26.
Question 17：Lines 271-273: How do the authors know about that? Please provide references.
Response：Thank you for your valuable advice. Selection criteria set by the author based on common sense, based on the environmental requirements of kitchen marble use.
Question 18： 3.3, Lines 285-286: Authors state that this formulation has better hydrophobic properties, only by the use of higher percentage of F as an exterior layer. Even though, I believe that this is a good reason, I do not believe that the authors should put it as certain. In contact angle measurements it is also important the roughness of the material, something that the authors do not know. I believe they should rephrase this as a hypothesis.
Response：Thank you for your valuable advice. The contact angle of water and cetane on formulation F3, F4 and F5 coating films were measured separately and the results are shown in Figure 5. Higher percentage of F of the film is just an ancillary verification tool as a hypothesis.
Question 19：Moreover, for XPS the percentage of F is calculated based on the other elements. Authors should also report what are the percentages of elements participating in the formulations, and actually show the higher percentage of F for the F3.
Response ：Thank you for your valuable advice. It can be seen from the paint formula that the amount of other ingredients added is basically the same, except for the addition ratio of HEA-HDI-TEOH-6. Therefore, the relative content of fluorine (peak integral area) can represent the relative amount of F in different formulations. The use of higher percentage of F of the film is just an ancillary verification tool.
Question 20：Line 307: How do the authors know that the F3 has higher oleophobicity? Which experiment did they make? If authors refer to cetane contact angle, they should make it clear from the beginning of the manuscript. For me it was a little confusing.
Response：Thank you for your valuable advice. Figure 5 has shown the cetane contact angle of F3, F4, F5. Greater cetane contact angle means better oleophobicity.
Question 21： Lines 326-329: Please add references.
Response：Thank you for your valuable advice. I have added reference [63] for these lines.
Question 22： Lines 334-335: I believe that better characterization for the surface morphology can be done with AFM. If the author have access to AFM it would be better to characterize with this technique.
Response：Thank you for your valuable advice. Yes, I agree with this suggestion, because AFM is better than SEM. But SEM is the only tool I can use.
Question 23： Lines 365-368: Please add references.
Response：Thank you for your valuable advice. I have added reference [66] for these lines.
Question 24： Lines 377-380: Please add references.
Response：Thank you for your valuable advice. I have added reference [67] for these lines.
Question 25： Lines 408-412: Please add references.
Response：Thank you for your valuable advice. I have added reference [69] for these lines.
Question 26： Have the authors tested the thermal degradation of these coatings? As the authors know, higher temperatures can also be present in these marbles during different preparations. What is the performance of their material under heat?
Response：Thank you for your valuable advice. I have tested the thermal degradation of the film of Formulation F3, and TGA figure was added and analysed.
Question 27： Figure 11: Even though the authors are referring the type of stains inside the text, I propose to show with arrows in one image, which is each stain
Response：Thank you for your valuable advice. I indicated the stains in the picture.
Round 2
Reviewer 1 Report
I find that the work is perfect he has corrected the corrections given I give my favorable opinion for the publication of this work and thank you.
Author Response
Comments: I find that the work is perfect he has corrected the corrections given I give my favorable opinion for the publication of this work and thank you.
Response: Thanks for your comments.
Reviewer 2 Report
It is very disappointing to read that the authors thank the reviewer for the suggestion/comment and they do not anything about it. The quality of the manuscript is still very poor and the manuscript does not deserve its publication in Coatings.
- Introduction is still too qualitative and does not provide quantitative results concerning similar fluorinated systems. It is too qualitative and has to be rewritten completely.
- the radiation intensity (mW/cm2) on the sample surface should be measured. The power of a lamp is not meaningful and the authors' reply is a nonsense. They do not want to measure the radiation intensity on the sample surface. This is the point. Radiation intensity is a key parameter in UV-curing, the authors have to learn about it.
-the glass transition temperature of the prepared coatings should be determined. Besides, the glass transition temperature refers to the amorphous part of the polymer, therefore it does not "disappear" after curing. Again, the authors have to learn about it. It is quite embarrassing to read the authors' reply.
- the completeness of the UV-curing reaction should be assessed through FT-IR spectroscopy. This is a scientific way to go on. The authors do not seem to know anything about it. I would suggest the authors to read some nice paper about fluorinated coatings (see, just as an examples, the nice papers from Bruno Ameduri and Roberta Bongiovanni)
- dynamic contact angle measurements should be performed, hence measuring the advancing and receding contact angle values and calculating the hysteresis, which is directly related to the surface roughness of the coatings. The authors should perform the analyses, rather than saying that they are not necessary
- the contact angle measurements should also be performed on both sides of the films, i.e. that exposed to air and that in contact with the substrate. Stating that "The side of the paint film in contact with the marble will never be applied and there is no necessary to testing data from this side. The fluorocarbon chain segments in the paint film will also migrate to the side of the film that is in contact with air, so the focus is on assessing the surface of the paint film." is a nonsense: the authors have to prove the migration.
-XPS measurements should be used for determining the F/C ratios. Different take-off angles should be employed for the analyses. This way, it could be possible to assess the possible presence of F concentration gradients. Again, it is a nonsense to state that the "The amount of C in the paint formulation is much greater than the amount of F, and due to measurement errors, the F/C in each formulation may be very close." XPS analyses are very reliable and accurate, WHEN BEING PERFORMED
- from an overall point of view, the Results and Discussion is plenty of results, but lacks their critical interpretation and justification. It should be completely rewritten. The efforts spent by the author do not show any improvement of this part of the manuscript
Author Response
The topic discussed in this paper is hydrophobic and oleophobic coatings for kitchen marble countertops, and the research idea is novelty. Fluorooctylethyl alcohol (TEOH-6), hexamethylene diisocyanate (HDI) and hydroxyethyl acrylate (HEA) were used to synthesize UV-curing monomers with fluorocarbon branched chains. The new monomer was added to UV-curing coating formulations. In addition, Hydrofluoric ether was added to promote more efficient migration of the fluorocarbon chains to the surface, thereby improving the hydrophobic and oleophobic properties of the coating films.
The second reviewer raised a number of questions, which are not used in the research of the hydrophobic and oleophobic properties of paint films. He requested that the radiation intensity (mW/cm2) on the sample surface should be measured, and the glass transition temperature of the prepared UV coatings should be determined, and the contact angle measurements should also be performed on both sides of the films, i.e. that exposed to air and that in contact with the substrate, etc. All these requests are not meaningful to the article and keep the reader from focusing on the novelty highlighted by the article.
If the reviewer's comments had been followed exactly, it would have resulted in a significant change in the structure of the article, making the novelty of the article unclear to the reader. Several other reviewers did not question any of these aspects either.
I have followed the comments of the other reviewers and revised the article to highlight the novelty of the article. I hope that my explanation could be understood.
Thank you very much!
Reviewer 3 Report
The authors have improved the manuscript a lot. Still, some points need clarification, and some corrections must be made.
1) In the Figure of FTIR, the authors did not add zoom images as proposed. It can help the reader to see the differences between the different samples. In the exact figure, the authors claim that the bands 1000-1400 can be found as the characteristic for the -F-. Still, they have to show references for that, and as I have proposed, they are to show with arrows or somehow the characteristic bands of all samples inside the figure.
2) In the comment about the two peaks of the HNMR. Authors have responded that this may be from dirty NMR tubes and due to the presence of the THF. Even though I can agree with the authors on their explanation, I have to say that in this case, they must present a new HNMR without these bands.
3) Comment 15: Authors claim that the different numbers of double bonds can lead to alteration in cross-linking. How about the reactivity of the other formulation? Is it the same? How about the steric hindrance of the different formulations? All these can show different kinetics and thus change the cross-linking. I advise the authors to use a reference that can strengthen their claims.
4) Comment 18: Authors should provide references for their claims here.
5) Comment 19: Here, the authors explain quantitative results from a technique where the percentages are calculated based on the elements participating and presented each time. The authors must show the percentages of all basic elements of the formulations to actually show the higher or lower percentages of F compared with other elements. Or they can show a ratio among the elements based on how many C, F, or other elements there are to show where more F is.
Author Response
Thank you for your recognition and encouragement. As for the point you mentioned, I response as the following:
- In the Figure of FTIR the authors did not add zoom images as proposed. It can help the reader to see the differences between the different samples in the exact figure, the authors claim that the bands1000-1400 can be found as the characteristic for the-F-. Still, they have to show references for that and as I have proposed they are to show with arrows or somehow the characteristic bands of all samples inside the figure.
Response: Thank you for your valuable advice. I have zoomed images in the manuscript, and attached reference for the characteristic of the F. It can be seen from Fig. 3(b) that the peak at 1140 cm-1 should be assigned to C-F absorption.
- In the comment about the two peaks of the HNMR. Authors have responded that this may be from dirty NMR tubes and due to the presence of the THF. Even though can agree with the authors on their explanation. I have to say that in this case they must present a new HNMR without these bands.
Response: Thank you for your valuable advice. To be honest, I cannot modify the graphs, nor can I re-synthesis the UV-cured monomers and get the data retested within one month. In order to make the peaks found at 1.65 ppm and 3.65 ppm more understandable to the reader, I have given interpretation in the article that these peaks are from the solvent DMF and do not affect the judgement of the structure of the UV-cured monomer. I hope that this explanation could be understood.
- Comment 15: Authors claim that the different numbers of double bonds can lead to alteration in cross-linking. How about the reactivity of the other formulation? Is it the same? How about the steric hindrance of the different formulations? All these can show different kinetics and thus change the cross-linking. I advise the authors to use a reference that can strengthen their claims.
Response: Thank you for your valuable advice. I have added reference for this inference.
- Comment 18: Authors should provide references for their claims here.
Response: Thank you for your valuable advice. I have added reference for this claim.
- Comment 19: Here the authors explain quantitative results from a technique where the percentages are calculated based on the elements participating and presented each time. The authors must show the percentages of all basic elements of the formulations to actually show the higher or lower percentages of F compared with other elements. Or they can show a ratio among the elements based on how many C, F, or other elements there are to show where more F is
Response: Thank you for your valuable advice. The integrated area of the XPS curve represents only the relative content of the surface elements. Since all formulations have the same total weight and the same elements, the F integrated area can be considered as a result of the relative content of F in the different formulations. Formulation F3 which has larger F integration area of the XPS curve represents a better hydrophobic and oleophobic property than formulations F4 and F5. This has been explained in the article also.
Round 3
Reviewer 3 Report
The authors have provided adequate explanations.
Author Response
Comments: The authors have provided adequate explanations.
Response: Thanks for your comments. As for English language, we have checked and improved.
