Thermal Analysis of Polyurethane Coatings Modified with Graphene and Modification Influence on Mechanical Properties of Hybrid Textile Materials Dedicated to Personal Protective Equipment

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The modification of polyurethane coating applied in outer layer of hybrid textile materials which is feasible by employing graphene into polymer background. A shift in the onset temperature of the polymer coating decomposition towards higher values after the incorporation of the graphene, leading to increase of thermal stability. The impact of the coating layers on the mechanical properties of hybrid textile materials occurs under tensile testing which unveils the potential of using such media as protective materials.

The paper deals with an interesting topic but certain improving modifications are necessary to become publishable at MDPI Coatings. In particular:

(A) How the absorbance and the endurance of the sample is affected by anisotropy and potential in-plane rotations [1,2] that has been proven to host powerful resonances and phase changes (magic angles)?

(B) The authors should physically explain the sharp peaks of Figures 4,5 where the Derivative Thermogravimetric (DTG) curve gets maximized at specific temperatures.

(C) The same analysis can be performed for alternative two-dimensional media which are famous for their durability and. The authors should comment appropriately in the revised version,

 

[1] Electromagnetic Analog to Magic Angles in Twisted Bilayers of Two-Dimensional Media, Phys. Rev. Applied, 2022.

[2] Magic angle butterfly in twisted trilayer graphene, Phys. Rev, Researcrh, 2023.

Author Response

#Reviewer 1:

The modification of polyurethane coating applied in outer layer of hybrid textile materials which is feasible by employing graphene into polymer background. A shift in the onset temperature of the polymer coating decomposition towards higher values after the incorporation of the graphene, leading to increase of thermal stability. The impact of the coating layers on the mechanical properties of hybrid textile materials occurs under tensile testing which unveils the potential of using such media as protective materials.

The paper deals with an interesting topic but certain improving modifications are necessary to become publishable at MDPI Coatings. In particular:

(A) How the absorbance and the endurance of the sample is affected by anisotropy and potential in-plane rotations [1,2] that has been proven to host powerful resonances and phase changes (magic angles)?

[1] Electromagnetic Analog to Magic Angles in Twisted Bilayers of Two-Dimensional Media, Phys. Rev. Applied, 2022.

[2] Magic angle butterfly in twisted trilayer graphene, Phys. Rev, Researcrh, 2023.

Answer 1 for Reviewer 1:

We appreciate the Reviewer's comments and agree that the topic presented should be investigated. However, the proposed studies are beyond the scope of the paper. In this article, we mainly focus on the application of graphene in PPE and the suggested studies can be described in another paper.

#Reviewer1 :

(B) The authors should physically explain the sharp peaks of Figures 4,5 where the Derivative Thermogravimetric (DTG) curve gets maximized at specific temperatures.

Answer 2 for Reviewer 1:

We thank the Editor for the valuable comment. We agree with the recommendation and have carefully improved that inaccuracy in the manuscript based on the provided remark

#Reviewer 1:

(C) The same analysis can be performed for alternative two-dimensional media which are famous for their durability and. The authors should comment appropriately in the revised version,

Answer 3 for Reviewer 1:

We would like to thank the Reviewer for the comment. Nevertheless, the proposed studies are beyond the scope of the paper. In this article, we mainly focus on the application of graphene in PPE and the suggested studies can be described in another paper.

Reviewer 2 Report

Comments and Suggestions for Authors

 

Coatings

Manuscript Number:  coatings-3541062

Title: "Thermal analysis of polyurethane coatings modified with graphene and the modification influence on mechanical properties of hybrid textile materials dedicated to personal protective equipment (PPE)"

Author(s): Emilia Irzmańska, Magdalena Jurczyk-Kowalska, Anna Boczkowska, Kamila Sałasińska, Kamila Strycharz, Olga Olejnik                          

The current paper focused on the modified polyurethane coatings in hybrid textile materials for PPE by incorporating graphene (0.25 wt.% and 0.5 wt.%). Thermogravimetric analysis revealed improved thermal stability, as evidenced by a higher decomposition onset temperature in a nitrogen atmosphere. 

The scientific subject could be of interest from a practical point of view, but some corrections must be made before being accepted for publication. Also, the recommendation is to revise the entire manuscript and the authors must explain more comprehensively their results.   

Introduction 

The authors fail to point out their starting interest on the subject and how they bring new contributions on it. The section must be improved. It may be beneficial to include additional bibliographical references in the introduction. For instance, on page 2, lines 47-51, there are no references supporting the statements in this paragraph. 

Materials and Methods 

2.2. Subsection. The term "Subsection" may not be the most appropriate subtitle. Perhaps renaming it to something more specific, such as "Sample Preparation," would be more appropriate.  

Results and discussion It may be better to start the Results and Discussion section with a short introductory paragraph before introducing the analysis of the foil samples. This approach would make the paper flow more smoothly and easier to follow. 

The discussion on thermal stability appears to be quite brief. I would suggest that the authors consider revisiting and expanding this paragraph to provide a more in-depth analysis.  

Page 7 line 214. ….monomers and polyol segments are obtained and finally degraded 14…. I appreciate the inclusion of references to support the argument. However, I noticed that the cited reference does not seem to directly relate to the content of this paragraph. Perhaps a more relevant source could be considered to strengthen the point being made. 

Page 8, line 223. You affirm that the….PU coatings with 0.25% and 0.5% graphene was lower in comparison to referential sample… Why is more lower? It would be helpful to provide an explanation or supporting argument to strengthen this observation.   

Page 8, line 233. I recommend you to insert a bibliographic reference.

Page 8. The discussion on DSCs appears to be quite brief. It may be beneficial to provide a more in-depth analysis to enhance clarity and support the findings.

Similarly, the FTIR analysis is addressed briefly. Expanding on this section with additional details and interpretation would help strengthen the discussion and provide greater clarity.

Since PPE is being discussed, it would be valuable to include air permeability and WVTR analyses. These tests provide important insights into breathability and water vapor transport in the new hybrid textile materials. It might be valuable to consider including such a study in your article, as it could provide additional insights and strengthen the overall analysis.

 

 

 

 

 

 

Comments for author File: Comments.pdf

Author Response

#Reviewer 2:

The current paper focused on the modified polyurethane coatings in hybrid textile materials for PPE by incorporating graphene (0.25 wt.% and 0.5 wt.%). Thermogravimetric analysis revealed improved thermal stability, as evidenced by a higher decomposition onset temperature in a nitrogen atmosphere.

The scientific subject could be of interest from a practical point of view, but some corrections must be made before being accepted for publication. Also, the recommendation is to revise the entire manuscript and the authors must explain more comprehensively their results.

Answer 1 for Reviewer 2:

We appreciate Reviewer’s suggestions and we decided to revise the entire manuscript, explain more comprehensively the obtained results as well as make necessary corrections. The changes are highlighted in yellow.

#Reviewer 2:

Introduction

The authors fail to point out their starting interest on the subject and how they bring new contributions on it. The section must be improved. It may be beneficial to include additional bibliographical references in the introduction. For instance, on page 2, lines 47-51, there are no references supporting the statements in this paragraph.

Answer 2 for Reviewer 2:

We thank Reviewer for valuable comments. We added some references supporting the statements in the mentioned paragraph.

[4] De Luca, P.; B.Nagy, J.; Macario, A. Nanomaterials Used in the Preparation of Personal Protective Equipment (PPE) in the Fight against SARS-CoV-2. Inorganics (Basel) 2023, 11.

[5] Basodan, R.A.M.; Park, B.; Chung, H.J. Smart Personal Protective Equipment (PPE): Current PPE Needs, Opportunities for Nanotechnology and e-Textiles. Flexible and Printed Electronics 2021, 6.

[6] Syduzzaman, M.; Hassan, A.; Anik, H.R.; Akter, M.; Islam, M.R. Nanotechnology for High-Performance Textiles: A Promising Frontier for Innovation. ChemNanoMat 2023, 9.

[7]. Bhattacharjee, S.; Joshi, R.; Chughtai, A.A.; Macintyre, C.R. Graphene Modified Multifunctional Personal Protective Clothing. Adv Mater Interfaces 2019, 6.

#Reviewer 2:

Materials and Methods

2.2. Subsection. The term "Subsection" may not be the most appropriate subtitle. Perhaps renaming it to something more specific, such as "Sample Preparation," would be more appropriate.

Answer 3 for Reviewer 2:

We would like to thank the Reviewer for the suggestion. We changed the subtitle for the more specific one: “Preparation of coating pastes and hybrid textile materials”.

#Reviewer 2:

Results and discussion It may be better to start the Results and Discussion section with a short introductory paragraph before introducing the analysis of the foil samples. This approach would make the paper flow more smoothly and easier to follow.

Answer 4 for Reviewer 2:

We appreciate the Reviewer's comments and have decided to add the following brief introduction to the Results and Discussion section: “The analysis of the prepared materials was carried out in two steps. In the first step, individual coating layers in the form of thin foils without textile support were investigated by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). Subsequently, in the case of coating application on the meta-aramid textile, the obtained hybrid textile materials were analyzed by means of tear resistance as well as scanning electron microscopy before and after mechanical testing.”.

#Reviewer 2:

The discussion on thermal stability appears to be quite brief. I would suggest that the authors consider revisiting and expanding this paragraph to provide a more in-depth analysis.

Answer 5 for Reviewer 2:

We thank Reviewer for the valuable suggestions. We expanded the mentioned paragraph, where demanded explanations have been provided.

#Reviewer 2:

Page 7 line 214. ….monomers and polyol segments are obtained and finally degraded 14…. I appreciate the inclusion of references to support the argument. However, I noticed that the cited reference does not seem to directly relate to the content of this paragraph. Perhaps a more relevant source could be considered to strengthen the point being made.

Answer 6 for Reviewer 2:

Thanking the Reviewer for the remarks we would like to say that the suggested changes have been made.

#Reviewer 2:

Page 8, line 223. You affirm that the….PU coatings with 0.25% and 0.5% graphene was lower in comparison to referential sample… Why is more lower? It would be helpful to provide an explanation or supporting argument to strengthen this observation.

Answer 7 for Reviewer 2:

The authors wish to thank the Reviewer for drawing attention to the error that was made.

#Reviewer 2:

Page 8, line 233. I recommend you to insert a bibliographic reference.

Answer 8 for Reviewer 2:

Thank you for pointing out our error. The sentence is false and inconsistent with the analysis performed. Appropriate changes have been introduced to the article regarding the description of the TG analysis.

#Reviewer 2:

Page 8. The discussion on DSCs appears to be quite brief. It may be beneficial to provide a more in-depth analysis to enhance clarity and support the findings..

Answer 9 for Reviewer 2:

We are thankful for the Reviewer’s comments. We have improved DSC discussion and the changed part is highlighted in yellow.  

#Reviewer 2:

Similarly, the FTIR analysis is addressed briefly. Expanding on this section with additional details and interpretation would help strengthen the discussion and provide greater clarity..

Answer 10 for Reviewer 2:

We would like to thank Reviewer for the comment. We have improved FTIR analysis section and the changed part is highlighted in yellow. Moreover, the FTIR discission has been moved to the section: 3.1. Foil samples analysis.

#Reviewer 2:

Since PPE is being discussed, it would be valuable to include air permeability and WVTR analyses. These tests provide important insights into breathability and water vapor transport in the new hybrid textile materials. It might be valuable to consider including such a study in your article, as it could provide additional insights and strengthen the overall analysis.

Answer 11 for Reviewer 2:

We appreciate Reviewer’s suggestions. In presented article we were focused mostly on thermal and mechanical properties. However, the suggested methods can be applied and described in the further research in the future..

 

Reviewer 3 Report

Comments and Suggestions for Authors

The coating of textiles applied to personal protective materials is often necessary, and the polyurethane (PU) pastes are widely used. In this regard, other additives are added in the PU pastes for enhanced performances. In this manuscript, grapheme as a filler is added into a PU paste for regulating the properties of meta-aramid fabric. The thermal stability and dispersivity of grapheme-containing PU pastes as well as the morphological structure and mechanical (tearing) properties of PU-coated fabrics are studied. The research is novel. The important technical pointed are clearly presented. The conclusion is supported by the data. Also, the manuscript is well organized. It can be accepted for publishing after minor revision.

 

Please note the following issues:

 

Regarding Title:

The abbreviation (PPE) in the title should be deleted.

 

Abstract Section:

The present abstract is simple. Only one important point is pointed out. Additional points relative to the research subject may be supplemented.

 

Introduction Section:

Line 32: “PPE (Personal Protective Equipment)” should be replaced by “PPE” because its full name and abbreviation have been mentioned and used in Line 26.

 

Materials and Methods Section:

Lines 108, 110, 120, and 136: Please note the punctuation marks -- “0,25 wt% and 0,5 wt%”, “0,6 mm” and “a thickness of 0,23-0,28”, and “0,15”. Please check the punctuation marks regarding numerical values in other places.

 

Line 114: “2.2.1. Hybrid textile materials”: The sequence number is not correct.

 

Regarding sub-titles:

It would be better if the sub-titles can be changed.

 

Original sub-titles:

2. Materials and Methods

2.1. Components

2.2. Subsection

2.2.1. Foil samples preparation

2.2.2. Hybrid textile materials preparation

2.3. Microstructure assessment

2.4. Thermogravimetric Analysis (TGA)

2.5. Differential Scanning Calorimetry (DSC)

2.6. Fourier Transform Infrared Spectroscopy (FT-IR) Absorbance Spectra Analysis

2.7. Tear resistance of hybrid textile materials

 

Revised sub-titles:

2. Materials and Methods

2.1. Materials

2.2. Preparation of coating pastes and hybrid textile materials

2.3. Measurements

2.3.1 Microstructure assessment

2.3.2 Thermogravimetric analysis (TGA)

2.3.3 Differential scanning calorimetry (DSC)

2.3.4 Fourier Transform Infrared Spectroscopy

2.3.5 Tear resistance of hybrid textile materials

 

Results and Discussion Section:

Line 257: “green orange” should be replaced by “green”.

 

The sequence number of the sub-titles is not correct.

Line 198: 3.1. Foil samples analysis 198; Line 263: 3.1. Hybrid textile materials analysis.

 

Regarding FT-IR spectra:

(Figure 8: FT-IR spectra of referential polyurethane coating and polyurethane coating containing 0.25 wt. % grapheneand 0.5 wt. % grapheme)

It seems to be the FT-IR spectra of PU pastes. If so, the FT-IR spectra should be moved into Section 3.1.

Author Response

#Reviewer 3:

The coating of textiles applied to personal protective materials is often necessary, and the polyurethane (PU) pastes are widely used. In this regard, other additives are added in the PU pastes for enhanced performances. In this manuscript, grapheme as a filler is added into a PU paste for regulating the properties of meta-aramid fabric. The thermal stability and dispersivity of grapheme-containing PU pastes as well as the morphological structure and mechanical (tearing) properties of PU-coated fabrics are studied. The research is novel. The important technical pointed are clearly presented. The conclusion is supported by the data. Also, the manuscript is well organized. It can be accepted for publishing after minor revision.

Please note the following issues:

Regarding Title:

The abbreviation (PPE) in the title should be deleted..

Answer 1 for Reviewer 3:

We would like to thank Reviewer for the comment. The abbreviation (PPE) in the title has already been deleted.

#Reviewer 3:

Abstract Section:

The present abstract is simple. Only one important point is pointed out. Additional points relative to the research subject may be supplemented.

Answer 2 for Reviewer 3:

We thank the Reviewer for paying attention to this issue. We added extra information as follows:

“The paper is focused on the modification of polyurethane coating applied in outer lay-er of hybrid textile materials dedicated to personal protective equipment. For this purpose, graphene with various weight fractions, i.e. 0.25 and 0.5 wt. % were intro-duced into the polyurethane matrix. The prepared pastes were implemented into me-ta-aramid fabric as coating. The results of thermogravimetric analysis of polymer coating showed a shift in the onset temperature of the polymer coating decomposition to higher values after graphene addition, which indicates an improvement in thermal stability. Considering mechanical properties, the coating implementation on me-ta-aramid fabric reduces tear resistance but it may be improved by addition of 0.5 wt. % of graphene. Such a hybrid textile material meets the tearing force requirements for protective clothing for firefighters according to the EN 469:2020”

#Reviewer 3:

Materials and Methods Section:

Lines 108, 110, 120, and 136: Please note the punctuation marks -- “0,25 wt% and 0,5 wt%”, “0,6 mm” and “a thickness of 0,23-0,28”, and “0,15”. Please check the punctuation marks regarding numerical values in other places.

Answer 3 for Reviewer 3:

We are grateful for paying attention to the mentioned mistake. We have already changed the incorrected punctuation marks.

#Reviewer 3:

Line 114: “2.2.1. Hybrid textile materials”: The sequence number is not correct.

Answer 4 for Reviewer 3:

We thank Reviewer for pointing out our mistake. We changed the subtitles based on the Reviewer’s suggestions.

#Reviewer 3:

Regarding sub-titles:

It would be better if the sub-titles can be changed.

Original sub-titles:

Materials and Methods

2.1. Components

2.2. Subsection

2.2.1. Foil samples preparation

2.2.2. Hybrid textile materials preparation

2.3. Microstructure assessment

2.4. Thermogravimetric Analysis (TGA)

2.5. Differential Scanning Calorimetry (DSC)

2.6. Fourier Transform Infrared Spectroscopy (FT-IR) Absorbance Spectra Analysis

2.7. Tear resistance of hybrid textile materials

Revised sub-titles:

Materials and Methods

2.1. Materials

2.2. Preparation of coating pastes and hybrid textile materials

2.3. Measurements

2.3.1 Microstructure assessment

2.3.2 Thermogravimetric analysis (TGA)

2.3.3 Differential scanning calorimetry (DSC)

2.3.4 Fourier Transform Infrared Spectroscopy

2.3.5 Tear resistance of hybrid textile materials.

Answer 5 for Reviewer 3:

We are thankful for the Reviewer’s comments and we changed the subtitles based on the presented suggestions.

#Reviewer 3:

Results and Discussion Section:

Line 257: “green orange” should be replaced by “green”.

Answer 6 for Reviewer 3:

We are grateful for pointing out our error. The mistake has been already corrected.

#Reviewer 3:

The sequence number of the sub-titles is not correct.

Line 198: 3.1. Foil samples analysis 198; Line 263: 3.1. Hybrid textile materials analysis.

Answer 7 for Reviewer 3:

We thank Reviewer for pointing out our errors. We corrected the mistakes based on the Reviewer’s suggestions

#Reviewer 3:

Regarding FT-IR spectra:

(Figure 8: FT-IR spectra of referential polyurethane coating and polyurethane coating containing 0.25 wt. % grapheneand 0.5 wt. % grapheme)

It seems to be the FT-IR spectra of PU pastes. If so, the FT-IR spectra should be moved into Section 3.1.

Answer 8 for Reviewer 3:

We confirm that the FTIR results of the tested materials refer to polyurethane and nanocomposites, not coated fabrics.

As suggested, we are moving the FTIR results to the section on the polyurethane films