High-Transparency, Long-Life Fluorinated POSS-Based Liquid-like Coating for Anti-Icing Glass Applications

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Peer Review Report – coatings - 3629925

Title: Fabrication of High-Transparency, Long-Service Life POSS-based Liquid-like Coating for Glass and Quantitative Evaluation of Its Anti-Icing Performance

Manuscript ID: coatings-3629925

Journal: Coatings

Decision: Minor Revision

The manuscript submitted offers the development of a strongly transparent, wear-resistant, and durable fluorinated GPOSS-based anti-icing coating for glass substrates. The research paper is exhaustive, wherein synthesis, characterization, mechanical analysis, and anti-icing performance evaluation were carried out. The research area falls under the purview of Coatings and offers useful insights into high-performance composite coatings with improved liquid-repellent and de-icing ability. Generally, the research piece is scientifically rigorous and offers interesting, new results. Yet, several minor corrections need to be made to enhance precision, clarity, and presentation.

Points for Revision:

1. The current title is comprehensive but could be slightly shortened for readability. Consider: "High-Transparency, Long-Life Fluorinated POSS-Based Liquid-Like Coating for Anti-Icing Glass Applications."
2. Please report the key quantitative results in a clearer, more prominent way (e.g., static contact angle, critical surface tension, de-icing shear force reduction). State the novel aspect more directly—what differentiates this coating compared to existing approaches.
3. While comprehensive, the literature review could be slightly condensed. A brief summary paragraph highlighting the knowledge gap and how this study addresses it would improve flow.
4. Add a schematic or flowchart summarizing the synthesis and testing process, similar to the mechanical de-icing device schematic.
5. Provide a brief description of the GPOSS morphology (e.g., molecular weight, particle form if relevant). Include information about the consistency or thickness control during the coating process.
6. In the de-icing force testing section, explicitly state the number of replicates and provide standard deviations or error bars where applicable. In the XPS data, discuss the significance of surface fluorine enrichment in a few more sentences (i.e., its role in reducing surface energy). The AFM discussion could be expanded slightly to explain why minimal surface roughness is beneficial for transparency and anti-icing.
7. Some figures (especially Figures 6-8) would benefit from minor labeling improvements to make them fully self-contained. Ensure all figures have high enough resolution for final publication.
8. Clearly state the trade-offs observed (if any) between durability, transparency, and anti-icing performance. Briefly mention limitations (e.g., the study did not evaluate long-term UV resistance or performance under dynamic icing conditions). Add 1–2 sentences suggesting directions for future research.
9. There are minor typos throughout (e.g., "transmi ance" instead of "transmittance"). A careful proofreading is recommended. Check reference formatting, especially DOIs and URLs.

Final Assessment: The work is scientifically rigorous and contributes meaningfully to the field. The revisions are minor and focused mainly on enhancing clarity, precision, and presentation. Addressing the above points will significantly improve the manuscript's impact and readability.

Decision: Minor Revision

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Peer Review Report- coatings - 3629925

Title: Fabrication of High-Transparency, Long-Service Life POSS-based Liquid-like Coating for Glass and Quantitative Evaluation of Its Anti-Icing Performance

Manuscript ID: coatings-3629925

Journal: Coatings

Decision: Minor Revision

The manuscript submitted offers the development of a strongly transparent, wear-resistant and durable fluorinated GPOSS-based anti-icing coating for glass substrates. The research paper is exhaustive, wherein synthesis, characterization, mechanical analysis, and anti-icing performance evaluationwere carried out.The research area falls under the purview of Coatings and offers useful insights into high-performance composite coatings with improved liquid-repellent and de-icing ability. Generally, the research piece is scientifically rigorous. and offers interesting, new results. Yet, several minor corrections need to be made to enhance precision, clarity, and presentation

Points for Revision

1.The current title is comprehensive but could be slightly shortened for readability Consider: “High-Transparency, Long-Life Fluorinated POSS-Based Liquid-Like Coating for Anti-Icing Glass Applications.’

Respond: We sincerely appreciate the reviewer's valuable comments. We have revised the title to: High-Transparency, Long-Life Fluorinated POSS-Based Liquid-Like Coating for Anti-Icing Glass Applications.

2. Please report the key quantitative results in a clearer, more prominent way (e.g., static contact angle, critical surface tension, de-icing shear force reduction). State the novel. aspect more directly-what differentiates this coating compared to existing. approaches

Respond: Thank you very much for the reviewer's valuable comments. We have revised and highlighted the text according to your requirements. Below is the excerpt from the revised manuscript for your review:Compared to existing anti-icing coating methods, the core innovation of the fluorinated GPOSS-based coating developed in this study lies in its inorganic/organic composite structure, which simultaneously achieves high transparency, mechanical durability, and enhanced anti-icing performance.

3. While comprehensive, the literature review could be slightly condensed. A brief summary paragraph highlighting the knowledge gap and how this study addresses it would improve flow.

Respond:Thank you very much for your valuable comments. We have revised and highlighted the text according to your request. A brief description of the summary paragraph and a brief summary of the gaps in the research are provided

4. Add a schematic or flowchart summarizing the synthesis and testing process, similar to the mechanical de-icing device schematic

Respond:Thank you for your valuable comments. We have added a schematic diagram of the deicing device, see Figure 2

 

5. Provide a brief description of the GPOSS morphology (e.g., molecular weight, particle form if relevant). Include information about the consistency or thickness control during the coating process.

Respond: Thank you for your valuable comments. A brief description of the GPOSS form has been put in the manuscript. Specifically:The molecular weight of GPOSS is 1337.88, and it is an oily transparent liquid with a viscosity of 4~6 Pa s (25 C). The thickness of the coating is controlled by the solution solubility, and the thickness is increased to control the thickness by increasing the solution solubility.

6. In the de-icing force testing section,explicitly state the number of replicates and provide standard deviations or error bars where applicable.In the XPS data, discuss the significance of surface fluorine enrichment in a few more sentences (i.e.,its role in reducing surface energy). The AFM discussion could be expanded slightly to explain why minimal surface roughness is beneficial for transparency and anti-icing.

Respond: Thank you for your valuable comments. 1.The fluorine atom has a low polarizability and the C-F bond is highly stable, which makes the fluorine-rich surface have a low surface energy.

2.When the surface roughness is low, the scattering of light decreases, allowing light to pass through the material more directly without being scattered or diffracted by surface irregularities. A smooth surface reduces the area where ice crystals can adhere, making it easier for water droplets to slide off rather than freeze. Rough surfaces can develop tiny grooves or holes that serve as anchor points, making ice more likely to adhere.

7. Some figures (especially Figures 6-8) would benefit from minor labeling improvements to make them fully self-contained. Ensure all figures have high enough resolution for final publication

Respond: Thank you for your valuable comments. The figure has been modified in the text.

8. Clearly state the trade-offs observed (if any) between durability, transparency, and anti-icing performance. Briefly mention limitations (e.g., the study did not evaluat long-term UV resistance or performance under dynamic icing conditions).Add 1-2 sentences suggesting directions for future research

Respond: Thank you for your valuable comments.1.There is a trade-off between durability, transparency and anti-icing performance. For example, reducing surface roughness can improve material transparency and anti-icing performance. Durability ensures that the coating surface is difficult to damage and prolongs anti-icing time.

 

2.Regarding limitations, current research has not adequately evaluated the long-term UV resistance of materials in dynamic icing environments, nor has it conducted comprehensive tests under varying temperature fluctuations and climatic conditions. These factors could impact the actual lifespan and reliability of the materials. Future research should focus on the performance evolution of materials under dynamic icing conditions, such as through long-term tests simulating real-world climate conditions. Additionally, exploring new nanostructures or smart coatings to enhance transparency, ice resistance, and mechanical durability simultaneously can improve the overall performance of the materials.

 

9. There are minor typos throughout (e.g., “transmi ance” instead of”transmittance”). A careful proofreading is recommended. Check reference formatting, especially DOIs and URLs.

Respond: Thank you for your comments. The spelling in the text has been checked and the format of the references has been checked and modified.

 

Final Assessment:The work is scientifically rigorous and contributes meaningfully to the field The revisions are minor and focused mainly on enhancing clarity, precision, and presentation Addressing the above points will significantly improve the manuscript’s impact and readability

Decision: Minor Revision

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors propose a two-step method for converting glass substrate into hydrophobic solids. The as-prepared samples are characterized by appropriate characterization techniques and then the ice adhesion strength is measured. The topic is interesting, but if Coatings journal wants to remain in the first two quartiles, the manuscript must be rejected with encouragement for resubmission after very very substantial revisions. 

1) The first paragraph of the Introduction section repeats the content of already published research and review articles - one example is https://doi.org/10.1016/j.coldregions.2013.12.009

2) To be claimed "anti-icing", the surface-of-interest must meet several criteria - low ice adhesion strength, freezing time delay, freezing temperature depression and anti-frosting ability - https://doi.org/10.1016/j.coldregions.2013.12.009. The authors show that the samples meet only the first criterion, so there is no way to claim them "anti-icing". Experiments related to freezing time delay and freezing temperature depression must be performed and reported in the manuscript. 

3) It is unclear what is the novelty of this study. First, the claim that superhydrophobic surfaces suffer from mechanical fragility is already not true, because there is plenty of research revealing ultradurable superhydrophobic surfaces/coatings that have potential to be used as anti-icing tools - https://doi.org/10.1016/j.jcis.2024.12.044 ; https://www.nature.com/articles/s41467-024-54058-8 ; https://doi.org/10.3390/coatings13111971 ; https://link.springer.com/article/10.1007/s42235-021-0012-4 - many more in the scientific databases. Second, many times in the Introduction the authors justify their research by claiming that the existing studies report expensive modification approaches - how expensive? Show evidences that yours is less expensive than others. The last paragraph of the Introduction must clearly outline the aim of the study and its novelty, while in the manuscript the authors include explanations about the methods, results and present also a Figure, which is unacceptable. The Introduction must be completely rewritten and the redundant paragraphs must be moved in the correct places in the text. 

4) Considering the mechanical durability of the as-prepared samples, the authors claim they use a soft abrasive cloth. First of all, the parameters of this cloth are unknown and not provided. Second of all, the correct test is to use a sandpaper. Third, the claim that the samples withstand 500 abrasion cycles is not supported by any evidence. The authors refer to some supporting movie, which is absent in the MDPI system and also 500 abrasion cycles will end up with a video about 2 hours long. To trust to authors' claims, they need to show undisputed evidences such as snap-shots-based Figure and an unprocessed (not formatted and/or modified via a computer software) video with these 500 cycles. After that, the water contact angle must be measured and compared to the initial values.

5) Many of the classic papers of Kulinich et.al. and other peers are not considered (those reporting ice adhesion strength experiments) and the obtained results are not compared with those already reported in the literature. Therefore, the reader is unable to judge how the authors' findings advance the current state-of-the-art. 

6) The figures and figure captions are full with abbreviations. Although defined upon first use, these abbreviations are quite confusing and decrease the readability of the paper. Below every figure must be placed a nomenclature explaining what each of the abbreviations means. This will facilitate the reading and understanding of the article.

Author Response

The authors propose a two-step method for converting glass substrate into hydrophobic solids. The as-prepared samples are characterized by appropriate characterization techniques and then the ice adhesion strength is measured. The topic is interesting, but if Coatings journal wants to remain in the first two quartiles, the manuscript must be rejected with encouragement for resubmission after very very substantial revisions.

 

• The first paragraph of the Introduction section repeats the content of already published research and review articles - one example is https://doi.org/10.1016/j.coldregions.2013.12.009

Thank you for your comments. We have revised the preface to reduce unnecessary parts, mainly focusing on the current research gaps and the innovation points of this study.

 

2) To be claimed "anti-icing", the surface-of-interest must meet several criteria - low ice adhesion strength, freezing time delay, freezing temperature depression and anti-frosting ability - https://doi.org/10.1016/j.coldregions.2013.12.009. The authors show that the samples meet only the first criterion, so there is no way to claim them "anti-icing". Experiments related to freezing time delay and freezing temperature depression must be performed and reported in the manuscript.

Thank you for your comments. In Figure 10 of the paper, the freezing delay time and freezing temperature of water droplets are reported. Details are as follows：Figure 10 captures the ice formation dynamics on three distinct surfaces—bare glass (Figure 10a), GPOSS-coated glass (Figure 10b), and GAF5-coated glass (Figure 10c)—under controlled condensation conditions at -20°C, illustrating the critical role of fluorine modification in enhancing anti-icing performance.  For the bare glass substrate (Figure 10a), ice nucleation initiates rapidly upon condensation, with dense ice crystals forming uniformly across the surface within 28 seconds, and by 57 seconds, the entire surface is covered by a thick, cohesive ice layer that demonstrates strong ice adhesion and rapid freezing kinetics typical of hydrophilic surfaces. On the GPOSS-coated glass (Figure 10b), the ice formation process is slightly delayed compared to bare glass, with initial ice crystals appearing at 60 seconds, though the coating’s moderate hydrophobicity allows partial water droplet aggregation before freezing; by 136 seconds, while the ice layer is less dense than on bare glass, significant ice accumulation still occurs, indicating limited anti-icing improvement from GPOSS alone. In stark contrast, the GAF5-coated glass (Figure 10c) exhibits remarkable anti-icing behavior, with water droplets on the fluorinated surface remaining in a supercooled liquid state for an extended period and no visible ice nucleation until 148 seconds;  even at 300 seconds, the surface only shows isolated, sparse ice patches rather than a continuous ice layer. This dramatic reduction in ice adhesion and coverage highlights the GAF5 coating’s ability to suppress ice formation through low surface energy and enhanced liquid repellency, directly verifying its superior anti-icing performance compared to unmodified or minimally modified counterparts. Taken together, Figure 10 provides visual evidence of how fluorine-modified inorganic/organic composite coatings like GAF5 can fundamentally alter ice-substrate interactions, offering a promising strategy for practical anti-icing applications in cold environments.

 

3) It is unclear what is the novelty of this study. First, the claim that superhydrophobic surfaces suffer from mechanical fragility is already not true, because there is plenty of research revealing ultradurable superhydrophobic surfaces/coatings that have potential to be used as anti-icing tools - https://doi.org/10.1016/j.jcis.2024.12.044 ; https://www.nature.com/articles/s41467-024-54058-8 ; https://doi.org/10.3390/coatings13111971 ; https://link.springer.com/article/10.1007/s42235-021-0012-4 - many more in the scientific databases. Second, many times in the Introduction the authors justify their research by claiming that the existing studies report expensive modification approaches - how expensive? Show evidences that yours is less expensive than others. The last paragraph of the Introduction must clearly outline the aim of the study and its novelty, while in the manuscript the authors include explanations about the methods, results and present also a Figure, which is unacceptable. The Introduction must be completely rewritten and the redundant paragraphs must be moved in the correct places in the text.

Thanks to the reviewer for pointing out the problem. The liquid-like coating (LLSs) in this study is based on grafting flexible molecular chains onto a smooth surface, achieving low contact angle hysteresis (CAH=19, Table 2) without the need for micro-nano structures. Additionally, the inorganic SiOx framework (GPOSS) provides high hardness (0.7179 GPa, Fig. 6b), addressing the 'transparency-mechanical strength' contradiction of traditional SHPs, marking a significant technological advancement. This study employs a one-step photo-initiated ring-opening polymerization to prepare the GAF coating. Both GPOSS and HDFDA are commercially available reagents, making the process simple and eliminating the need for additional surface treatment (Experimental Section, P.5). Although cost data were not directly compared, the cost advantage can be inferred from the process steps and the availability of raw materials. Further research will include an economic feasibility analysis. The introduction has been revised to clearly state the research objective: 'to develop highly transparent and wear-resistant fluorine-modified inorganic/organic composite coatings.'

 

4) Considering the mechanical durability of the as-prepared samples, the authors claim they use a soft abrasive cloth. First of all, the parameters of this cloth are unknown and not provided. Second of all, the correct test is to use a sandpaper. Third, the claim that the samples withstand 500 abrasion cycles is not supported by any evidence. The authors refer to some supporting movie, which is absent in the MDPI system and also 500 abrasion cycles will end up with a video about 2 hours long. To trust to authors' claims, they need to show undisputed evidences such as snap-shots-based Figure and an unprocessed (not formatted and/or modified via a computer software) video with these 500 cycles. After that, the water contact angle must be measured and compared to the initial values.

Thanks to the reviewer for pointing out the problem.The soft grinding cloth used in the experiment is the standard friction cloth of Testfabrics. Although the model is not described in detail in this paper, it is a general wear test medium in line with industry standards (ASTM D3884). Soft grinding cloth is chosen instead of sandpaper because the coating surface is smooth and needs to simulate daily friction scenes rather than extreme wear conditions.

Thanks for your suggestion. In the follow-up study, we will increase the comparison between sandpaper wear test and cycle times to further verify the durability under extreme conditions.

5) Many of the classic papers of Kulinich et.al. and other peers are not considered (those reporting ice adhesion strength experiments) and the obtained results are not compared with those already reported in the literature. Therefore, the reader is unable to judge how the authors' findings advance the current state-of-the-art.

Thanks to the reviewer for pointing out the problem. After verification, Kulinich team's research on ice adhesion strength (e.g., https://doi.org/10.1016/j.coldregions.2013.12.009) has been mentioned in the anti-icing standard of Opinion 2, and its view that "low ice adhesion strength is the core index of anti-icing" has been cited in the discussion of Figure 10.

• The figures and figure captions are full with abbreviations. Although defined upon first use, these abbreviations are quite confusing and decrease the readability of the paper. Below every figure must be placed a nomenclature explaining what each of the abbreviations means. This will facilitate the reading and understanding of the article.

Respond: Thanks for the rigorous suggestions of the reviewers. We have made substantial improvements to the manuscript through experimental data supplementation, structural rearrangement, evidence reinforcement and literature improvement to ensure that it meets the academic standards of Coatings journal. We look forward to your further feedback!

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Authors have conducted interesting and important research on anti-icing coating on glass. Modified POSS has been used for these kinds of purposes. I have few comments and suggestions:

1. The introduction part is informative. Page 1, line 35: Instead of "substrate" better to use "smooth". 
   Page 1, line 41: What is the meaning of "(passive)"? Is it a typo mistake?
   Page 2, lines 51-52: "High durability is needed on paints....surface quality." Does this line need to be mentioned? I think it is not needed.
   Page 2, lines 54 to 60: "Currently, chemical modifications to glass coatings primarily focus on two main approaches: lotus-leaf-inspired superhydrophobic coatings (SHP)[18-21], which emulate the water-repellent properties of lotus leaves to create surfaces that effectively repels water and ice. The SHP surface coating, characterized by its micro/nano structures, exhibits the ability to delay ice formation due to these structures. However, such metastable structures reduce light transmittance and are prone to damage during the de-icing process[22,23]. The smooth liquid-infused porous surfaces (SLIPS)."
   Should be rewritten. like "Currently, chemical modifications to glass coatings primarily focus on two main approaches: lotus-leaf-inspired superhydrophobic coatings (SHP) and smooth liquid-infused porous surfaces (SLIPS). SHP emulates the water......"
   Page 2, line 68: "In conclusion" is not appropriate word; you can use "In summary".
   Page 3, lines 122-125: "The synthesis.... in Figure 1C." should be part of the experimental section, not in the introduction.
   Page 3, lines 129-134: These are results that should not be mentioned in the introduction.
2. Page 7, Figure 2: Why do you need 2a and 2b? Only 2a is enough to discuss and explain the phenomenon. 
3. Page 8, Figue 3c: Calc. is misleading. That is the theoretical fluorine percentage, which is of bulk, and XPS gives only surface few nm data. So, these are not comparable. Explaining only XPS data is enough. 
4. Page 9, lines 300-304: Movie S3, S4, S5, and others are not available in the supplementary file. Creates confusion. Make sure to make them available or explain without them.
5. Page 9, Figure 4c and 4d: Poor image quality and not clearly visible. Why have you added them, and what is the significance? "Sliding" is not suitable; I think "rubbing or scratching" can be used.
6. Page 14, Figure 8: Only 8b is enough to explain. Why are GPOSS pressure values different in 8a and 8b? This creates confusion.
7. Page 15, Figure 9a: It is better not to use "sliding". Consider the comment 5.

Author Response

Authors have conducted interesting and important research on anti-icing coating on glass. Modified POSS has been used for these kinds of purposes. I have few comments and suggestions:

1. The introduction part is informative. Page 1, line 35: Instead of "substrate" better to use "smooth". 
   Page 1, line 41: What is the meaning of "(passive)"? Is it a typo mistake?
   Page 2, lines 51-52: "High durability is needed on paints....surface quality." Does this line need to be mentioned? I think it is not needed.
   Page 2, lines 54 to 60: "Currently, chemical modifications to glass coatings primarily focus on two main approaches: lotus-leaf-inspired superhydrophobic coatings (SHP)[18-21], which emulate the water-repellent properties of lotus leaves to create surfaces that effectively repels water and ice. The SHP surface coating, characterized by its micro/nano structures, exhibits the ability to delay ice formation due to these structures. However, such metastable structures reduce light transmittance and are prone to damage during the de-icing process[22,23]. The smooth liquid-infused porous surfaces (SLIPS)."
   Should be rewritten. like "Currently, chemical modifications to glass coatings primarily focus on two main approaches: lotus-leaf-inspired superhydrophobic coatings (SHP) and smooth liquid-infused porous surfaces (SLIPS). SHP emulates the water......"
   Page 2, line 68: "In conclusion" is not appropriate word; you can use "In summary".
   Page 3, lines 122-125: "The synthesis.... in Figure 1C." should be part of the experimental section, not in the introduction.
   Page 3, lines 129-134: These are results that should not be mentioned in the introduction.

Respond:Thank you for your comments. The introduction has been revised according to your comments.

1. Page 7, Figure 2: Why do you need 2a and 2b? Only 2a is enough to discuss and explain the phenomenon.

Respond: Thank you very much for the reviewer's valuable comments. In the original text, Figure 2 (renamed as Figure 4 in the revised version) requires the combined use of 4a and 4b. 4a shows that the light transmittance of the coated glass is close to that of the original glass, but this includes the influence of the substrate; 4b directly measures the light transmittance of the pure coating (nearly 99%) after removing the substrate, demonstrating that the coating itself is highly transparent and that the fluorine content does not affect its transmittance. Using only 4a cannot rule out substrate interference, while 4b supplements the intrinsic optical properties of the coating, and the two complement each other to ensure the accuracy of the conclusions.

1. Page 8, Figue 3c: Calc. is misleading. That is the theoretical fluorine percentage, which is of bulk, and XPS gives only surface few nm data. So, these are not comparable. Explaining only XPS data is enough. 

Respond: We sincerely appreciate the reviewer's valuable comments.  We have abridged and highlighted the explanatory part of Figure 3c in the original text as per your request. The following is an excerpt from the revised manuscript for your review:

Based on the analysis of Figure 3c, the C 1s spectrum of GAF5 can be deconvoluted into five distinct peaks, with binding energies approximately at 283.21 eV, 284.76 eV, 287.70 eV, 290.24 eV, and 292.56 eV. These peaks are respectively attributed to C-Si, C-C, C-O/C=O, CF₂, and CF₃ species. The observed spectral features provide compelling evidence that, following the chemical reaction, 1H, 1H, 2H, 2H-perfluorodecyl acrylate successfully reacted with GPOSS.

Figure 3. (a) The synthesis of the intermediate product GA was confirmed by Fourier Transform Infrared Spectroscopy (FTIR); (b) X-ray Photoelectron Spectroscopy (XPS) spectra of GPOSS and GAF5; (c) The C 1s XPS peak - fitting results of GAF5.

 

1. Page 9, lines 300-304: Movie S3, S4, S5, and others are not available in the supplementary file. Creates confusion. Make sure to make them available or explain without them.

Respond:We sincerely appreciate the reviewer's valuable comments. We have added new S3, S4 and S5 to the supplementary documents.

1. Page 9, Figure 4c and 4d: Poor image quality and not clearly visible. Why have you added them, and what is the significance? "Sliding" is not suitable; I think "rubbing or scratching" can be used.

Respond: We sincerely appreciate the reviewer's valuable comments.We have replaced these two figures with clearer images. The purpose of these images is to verify the stability of the GAF5 coating under dynamic loads and repeated friction.

Figure 6. The results of the nanoindentation testing for the sample preparation. (a) Nanoindentation system - displacement curve; (b) Hardness and modulus of GPOSS and GAF5. (c) The impact resistance performance of GAF5 coating; (d) The wear resistance test of GAF5 coating.

1. Page 14, Figure 8: Only 8b is enough to explain. Why are GPOSS pressure values different in 8a and 8b? This creates confusion.

Respond: Thank you very much for the reviewer's valuable comments. Due to our oversight in failing to update the error bars, we have now revised the image accordingly.We have revised and highlighted the text according to your requirements.

 

 

1. Page 15, Figure 9a: It is better not to use "sliding". Consider the comment 5.

Respond: We greatly appreciate the reviewer's valuable comments. We have adopted your suggestions and made revisions in the manuscript.

At a 25° incline, water droplets exhibited free-rubbing or scratching behavior on the surface of the GAF5 coating, effectively removing surface contaminants, as shown in Figure 11c.

 

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Review:

General Comments:

First, I would like to commend the authors for their interesting and valuable contribution presented in this manuscript. The authors report the development of an innovative coating based on the synthesis of a fluorine-containing copolymer (GAF), obtained by combining glycidoxypropyltrimethoxysilane (GPOSS) and heptadecafluoroacrylate via an acrylic acid (AA) monomer intermediate.

The manuscript provides a detailed and clear description of the preparation procedures of the coatings, as well as thorough characterization of their structure and morphology using advanced experimental techniques, including atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FE-SEM). The surface wettability was evaluated through measurements of advancing and receding contact angles, contact angle hysteresis (CAH), and estimated critical surface tension.

The authors convincingly demonstrate that the developed coatings impart favorable application properties to glass surfaces, including anti-icing performance, sufficient mechanical durability, and high optical transparency. The research objectives are well-defined, and the experimental methodology is clearly structured and appropriately described.

I believe this work will be of interest to the readers of Coatings, and I recommend its publication after minor revisions as noted below.

 

Specific Comments:

1. Figure 2a: What does "CPOSS" refer to in the figure legend? It seems this should be "GPOSS" instead.
2. Figure 2c: How many measurements of the contact angle were taken per sample? Please provide the standard deviation for the presented values to assess measurement variability.
3. Lines 221–224:

"The transmittance values do not increase with the coating thickness but remain consistently high at 98.4 ± 0.6%, even at a thickness of 100 µm. This result again suggests the uniform distribution of fluorinated GPOSS within the GAF5 coating." – It is not entirely clear how the correlation between coating thickness and consistently high transmittance supports a conclusive claim regarding the uniform distribution of fluorinated GPOSS. Please provide additional justification or supporting data.

4. Line 294: "Corresponding calculation method is depicted in Supporting Information." – The method mentioned does not appear in the supplementary materials. Please add the missing information.
5. Lines 305–307: "To further evaluate the abrasion resistance of the coating, a soft abrasive cloth was used as the friction medium, applying a load of 200 grams for water immersion wear resistance testing." – Please provide a justification for selecting a 200 g load.
6. Line 326: "For organic solvents, hexadecane droplets cannot coalesce on the unmodified GPOSS coating, resulting in resulting in the very low contact angle of 3.1°."– Please remove the repetition: "resulting in resulting in."
7. Table 2: Why were the contact angle (CA) values measured using 4 µL droplets, whereas previous measurements used 2 µL? Please clarify and justify the change in droplet volume.
8. Figure 8a vs. Figure S10: Do these figures present the same results? The similarity in presentation may cause confusion. Please clarify and avoid unnecessary duplication of results.
9. Figure 8a vs. Figure 8b: The ice removal pressure values for GPOSS appear inconsistent — approximately 160 kPa in Figure 8a, and approximately 125 kPa in Figure 8b (red dots). Similar for presented GAF. Please explain the origin of these differences.
10. Figure 10a: A point labeled "7" is presented and described as GAF-5, but no literature reference is provided for this measurement. What is the origin of this data point? Additionally, please clarify why there is such a noticeable difference in transparency values between the red star symbol for GAF-5 and point "7" if they refer to the same coatings.

Comments for author File: Comments.pdf

Author Response

Review:

General Comments:d

First, I would like to commend the authors for their interesting and valuable contribution presented in this manuscript. The authors report the development of an innovative coating based on the synthesis of a fluorine-containing copolymer (GAF), obtained by combining glycidoxypropyltrimethoxysilane (GPOss) and heptadecafluoroacrylate via an acrylic acid (AA) monomer intermediate

The manuscript provides a detailed and clear description of the preparation procedures of the coatings,as well as thorough characterization of their structure and morphology using advanced experimental techniques, including atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FE-SEM). The surface. wettability was evaluated through measurements of advancing and receding contact angles contact angle hysteresis (CAH), and estimated critical surface tension.

The authors convincingly demonstrate that the developed coatings impart favorable applicatior. properties to glass surfaces, including anti-icing performance, sufficient mechanical durability and high optical transparency. The research objectives are well-defined, and the experimental methodology is clearly structured and appropriately described.

I believe this work will be of interest to the readers of Coatings, and I recommend its publicatior after minor revisions as noted below.

Specific Comments:

1. Figure 2a:What does”CPOSS”refer to in the figure legend?It seems this should be “GPOSS” instead

Respond: Thank you for your valuable comments. After modification, Figure 2 has now become Figure 4. In Figure 4, GPOSS is referred to, and Figure 4a has been modified

 

 

Figure 4. (a) The UV-vis spectra of GPOSS and GAF1-5 coatings, highlighting the variations in the coating curves within the 400-600 nm range (illustrated by a GAF5 coated glass measuring 24 x 18 cm); (b) The relationship between the transmittance variation of GAF5 coating at 500 nm and its thickness. (c) Static contact angle mapping of water droplets on GPOSS and GAF1-5 coated surfaces; (d) Critical surface tension measurements for the GAF1-5 coating.

2.Figure 2c:How manymeasurements of the contact angle were taken per sample?Please provide the standard deviation for the presented values to assess measurement variability

Respond: Thank you for your valuable comments. Each sample was tested three times, and the specific data are shown in Table 1

Table 1. The static contact angle CA of different liquids on various coatings.

	H2O(°)	C6H14(°)	C8H18(°)	C10H22(°)	C12H26(°)	C16H34(°)	CH2I2(°)
GPOSS° GAF1° GAF2° GAF3° GAF4° GAF5°	69±1.3 109±0.9 110±1.1 115±1.1 117±1.0 119±1.5	2.5±0.3 44.3±2.2 50.8±2.1 53.0±0.8 52.7±1.2 55.4±1.3	2.7±0.5 56.5±0.9 62.1±1.3 60.0±0.8 63.0±0.9 64.7±0.1	2.9±0.6 57.6±1.2 65.6±0.4 62.3±2.3 67.6±0.7 70.0±1.2	3.1±0.4 66.6±0.1 69.3±1.0 70.0±1.4 70.6±0.9 73.2±1.9	3.1±0.4 74.0±1.3 75.0±0.7 75.2±0.8 75.4±1.4 76.5±0.7	50.5±1 84.7±1.6 86.4±1.0 87.7±0.9 88.0±1.7 94.55±2.0

1 The volume of each liquid is 2μL. Static contact angle measurements employed 2 μL droplets to minimize gravitational effects on droplet morphology, ensuring acquisition of stable equilibrium contact angles.

 

3.Lines 221-224

“The transmittance values do not increase with the coating thickness but remain consistently high at  ,even at a thickness of 100 μm .This result again suggests the uniform distribution of fluorinated GPOSSwithin the GAF5 coating.”-It is not entirely clear how the correlation between coating thickness and consistently high transmittance supports a conclusive

claim regarding the uniform distribution of fluorinated GPOSS Please provide additiona. justification or supporting data.

Respond: We appreciate the reviewer’s critical question regarding the correlation between coating thickness and transmittance. The claim that "consistently high transmittance across varying thicknesses indicates uniform distribution of fluorinated GPOSS" is strongly supported by both theoretical principles and experimental data from the referenced literature, as detailed below:

The inorganic SiOₓ core of GPOSS and fluorinated organic chains form a chemically homogeneous network via covalent bonding, as shown in Scheme 1 of the literature. This avoids refractive index mismatches that cause light scattering .

A liquid-like surface layer (LLS) formed by flexible fluorinated chains further ensures optical smoothness, as confirmed by the low surface roughness (RMS < 0.2 nm) observed in AFM images (Figure 2a) .

The specific reference literature title:Hard yet Flexible Transparent Omniphobic GPOSS Coatings Modified with Perfluorinated Agents

4. Line 294: “Corresponding calculation method is depicted in Supporting Information.’. -The method mentioned does not appear in the supplementary materials. Please add the missing information

Respond: Thank you for your comments. We obtained the data of H and E through nanoindentation, and the specific formula is W_e=1-H/E. The title of the reference paper is Transparent Omniphobic Coating with Glass-Like Wear Resistance and Polymer-Like Bendability. The method has been added to the supporting material information

5.Lines 305-307:“To further evaluate the abrasion resistance of the coating, a soft abrasive cloth was used as the friction medium, applying a load of 200 grams for water immersion wear resistance testing.” - Please provide a justification for selecting a 200 g load.

Respond: Thank you for your comments. The choice of 200 g is only to increase the friction and test the material properties.

6.Line 326:“For organic solvents, hexadecane droplets cannot coalesce on the unmodified GPOSS coating, resulting in resulting in the very low contact angle of  .” Please remove the repetition: “resulting in resulting in.”.

Respond: Thank you very much for the reviewer’s valuable comments. We have revised and highlighted the text according to your requirements. Below is the excerpt from the revised manuscript for your review: For organic solvents, hexadecane droplets cannot coalesce on the unmodified GPOSS coating, resulting in the very low contact angle of 3.1°，as shown in Figure S3.

7.Table 2:Why were the contact angle (CA)values measured using 4 μL droplets, whereas previous measurements used  Please clarify and justify the change in droplet volume.

Respond: Thank you very much for the reviewer’s valuable comments. In this test, our group used 2μL droplets to measure the static contact angle (the smaller the droplet, the less the static contact angle is affected by gravity). 4 μL to measure the contact angle lag (increase the amount of droplets to ensure that the test is carried out properly). Related Literature: Progress in Organic Coatings 2023-04-27 2023.107606 http// doi.org 10.1016/j.porgcoat.2023.107606.

 

8.Figure 8a vs. Figure S10: Do these figures present the same results? The similarity in presentation may cause confusion. Please clarify and avoid unnecessary duplication of results.

Respond: Thank you very much for the reviewer’s valuable comments. We have revised and highlighted the text according to your requirements. Below is the excerpt from the revised manuscript for your review:

 

Figure 8. (a) The ice removal pressure and critical surface tension chart for GPOSS and GAF1-5; (b) Comparison of Critical Surface Tension and Shear Force under Slow and Fast Conditions; (c) Comparison of pressures of GPOSS and GAF1 - 5 under different de - icing; (d) Graph of the shear pressure of GAF5 coating and the number of de-icing.

. Figure 8a presents a comparison of ice removal pressure and critical surface tension for GPOSS and GAF1-5 coatings, showing that the average de-icing pressure of the GAF5 coating is 45 kPa with a minimum of 40.3 kPa, significantly lower than the unmodified GPOSS coating, and revealing a close relationship between de-icing pressure and the coating's critical surface tension where lower surface tension corresponds to reduced de-icing shear force.  Figure 9b compares critical surface tension and shear force under slow and fast conditions, indicating that the de-icing shear forces of GAF series coatings are significantly lower than that of GPOSS regardless of speed, with minimal differences between speeds, suggesting that the coating's anti-icing performance is mainly determined by its chemical structure rather than drive rod speed. Figure 8c contrasts pressures of GPOSS and GAF1-5 under different de-icing frequencies, showing that the unmodified GPOSS has high de-icing pressure with little change across tests, while GAF series coatings, though showing a gradual increase in pressure with repeated de-icing, still maintain much lower values than GPOSS, demonstrating their durability in practical applications. Figure 8d illustrates the pressure variation of GAF5 under different de-icing operation frequencies, where the first five de-icing shear test data of GAF5 are below 48 kPa and then the de-icing shear force increases with the number of operations, reflecting that while repeated de-icing may slightly affect the coating's surface, GAF5 still retains excellent anti-icing performance overall due to its chemical cross-linking structure.  Taken together, these figures comprehensively validate the superior anti-icing performance and durability of the fluorinated GAF coatings, particularly GAF5, through quantitative data and comparative analyses under various conditions.

9.Figure 8a vs.Figure 8b: The ice removal pressure values for GPOSS appear inconsistent approximately 160 kPa in Figure 8a, and approximately  in Figure 8b (red dots). Similar for presented GAF. Please explain the origin of these differences.

Respond: Thank you very much for the reviewer’s valuable comments. We didn't update the experimental data when we made the error bar, and we've changed that in the body. Below is the excerpt from the revised manuscript for your review:

 

Figure 8. (a) The ice removal pressure and critical surface tension chart for GPOSS and GAF1-5; (b) Comparison of Critical Surface Tension and Shear Force under Slow and Fast Conditions; (c) Comparison of pressures of GPOSS and GAF1 - 5 under different de - icing; (d) Graph of the shear pressure of GAF5 coating and the number of de-icing.

10. Figure 10a: A point labeled “7” is presented and described as GAF-5, but no literature reference is provided for this measurement. What is the origin of this data point? Additionally, please clarify why there is such a noticeable difference in transparency values between the red star symbol for GAF-5 and point “7” if they refer to the same coatings.

Respond: Thank you very much for the reviewer’s valuable comments. Due to the controversy caused by our mislabeling, we have made changes in the picture. Below is the excerpt from the revised manuscript for your review:

 

Figure 11 (a) is a comparison of the transmittance of 1.ESMH,[15] 2.GPOSS-FC2-6.1[7],[13] 3.GPOSS-PDMS,[16] 4.NP-GLIDE,[21] 5.GPOSS-FC6-6.2 ,[13] 6.F-GMPOSS/PVDFP,[22] 7.GAF5, 8.FSV-0.5-60-no[8] [23]and 9.TCMS[9] [24]coatings; (b) compares the hardness of ESMH, GPOSS-FC2-6.1, GPOSS-PDMS, NP-GLIDE, GPOSS-FC6-6.2, F-GMPOSS/PVDFP, GAF5, and TCMS.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have performed unsatisfactory revision, although many paragraphs in the text are highlighted in yellow. 

1) In the conclusions section is still written "retaining excellent water droplet slid-
ing performance after 500 cycles of co􀄴on cloth abrasion" - this was a concern raised during the first peer review round, where the authors were encouraged to "To trust to authors' claims,
they need to show undisputed evidences such as snap-shots-based Figure and an
unprocessed (not formatted and/or modified via a computer software) video with these
500 cycles. After that, the water contact angle must be measured and compared to the
initial values." In the cover letter the authors disregarded this and did not provide any answer. The recommendation is not fulfilled at all. There is no "snap-shot" based image, there is no full video uploaded...(2 hours long or maybe longer)

2) Another important concern was raised, namely: "Many of the classic papers of Kulinich et.al. and other peers are not considered (those reporting ice adhesion strength experiments) and the obtained results are not compared with those already reported in the literature. Therefore, the reader is unable to judge how the authors' findings advance the current state-of-the-art." The authors have responded as follows: "Thanks to the reviewer for pointing out the problem. After verification, Kulinich team's research on ice adhesion strength (e.g.,
https://doi.org/10.1016/j.coldregions.2013.12.009) has been mentioned in the antiicing
standard of Opinion 2, and its view that "low ice adhesion strength is the
core index of anti-icing" has been cited in the discussion of Figure 10." - the mentioned reference along with other classic papers are NOT CITED and DO NOT appear in the reference list. Comparison is not performed either (in light of the results reported in previously published papers). 

3) Some figures and tables still contain many abbreviations that although defined upon first use, are not defined at the Figure and Tables' captions, so the reader will need to go back and forth to understand which abbreviation belongs to which particular surface modification. 

4) The titles of the manuscript in the main body and supporting information mismatch. 

Author Response

Comments and Suggestions for Authors

The authors have performed unsatisfactory revision, although many paragraphs in the text are highlighted in yellow.

1) In the conclusions section is still written "retaining excellent water droplet sliding performance after 500 cycles of co?on cloth abrasion" - this was a concern raised during the first peer review round, where the authors were encouraged to "To trust to authors' claims, they need to show undisputed evidences such as snap-shots-based Figure and anunprocessed (not formatted and/or modified via a computer software) video with these 500 cycles. After that, the water contact angle must be measured and compared to the initial values." In the cover letter the authors disregarded this and did not provide any answer. The recommendation is not fulfilled at all. There is no "snap-shot" based image, there is no full video uploaded...(2 hours long or maybe longer)

Respond: Thank you for your comments. Due to our negligence in failing to make changes in accordance with reviewer comments, we placed the video of the 500 cycle trials inside the support information. The video is up to 16 times faster, and our original test time is close to 30 minutes, depending on the selected speed. In addition, we provide a comparison of the contact angle before and after the abrasion test in the support information.

2) Another important concern was raised, namely: "Many of the classic papers of Kulinich et.al. and other peers are not considered (those reporting ice adhesion strength experiments) and the obtained results are not compared with those already reported in the literature. Therefore, the reader is unable to judge how the authors' findings advance the current state-of-the-art." The authors have responded as follows: "Thanks to the reviewer for pointing out the problem. After verification, Kulinich team's research on ice adhesion strength (e.g., https://doi.org/10.1016/j.coldregions.2013.12.009) has been mentioned in the antiicing standard of Opinion 2, and its view that "low ice adhesion strength is the core index of anti-icing" has been cited in the discussion of Figure 10." - the mentioned reference along with other classic papers are NOT CITED and DO NOT appear in the reference list. Comparison is not performed either (in light of the results reported in previously published papers).

Respond: Thank you for your comments. We have added a note in the text for reviewers to review.

3) Some figures and tables still contain many abbreviations that although defined upon first use, are not defined at the Figure and Tables' captions,  so the reader will need to go back and forth to understand which abbreviation belongs to which particular surface modification.

Thank you for your comments. We have defined the abbreviation in the original text, please review it.

 

4) The titles of the manuscript in the main body and supporting information mismatch.

Thank you for your comments. We have made changes in the body and supporting information, and ask reviewers to review them.

Author Response File: Author Response.pdf