Composite Films of Polydimethylsiloxane and Micro-Graphite with Tunable Optical Transmittance
Round 1
Reviewer 1 Report
The paper reports an interesting study on the fabrication of PDMS composite films with tunable optical transmittance properties. I recommend it for publication after minor revisions.
Generally speaking, the work could have a good scientific soundness but it should be organized in a clearer manner.
Some recent articles on the use of nanocarbons in high performance composites should be included in the reference list:
1) doi: 10.3390/polym11050857
2) doi: 10.1021/nn103523t
3) doi: 10.1016/j.cej.2016.09.131
4) doi: 10.1016/j.carbon.2019.04.085
5) doi: 10.1016/j.compscitech.2018.01.008
6) doi: 10.1038/s41598-019-40828-8
7) doi: 10.1016/j.compositesb.2019.03.076
8) doi: 10.1016/j.compositesa.2019.05.008
9) doi: 10.1016/j.snb.2019.03.117
10) doi: 10.1016/j.compscitech.2018.11.003
In the experimental part, the materials and the formulation adopted must be properly presented. The authors should consider the possibility to include a Table reporting codename and formulation of each sample. Raw materials are better described. Amorphous graphite is a microcrystalline graphite. Who was the supplier? Which are the main characteristics of this graphite grade?
The authors are recommended to divide the experimental section into three subsections:
1) Materials
2) Preparation routes
3) Characterizations
Aiming to improve the readability of the manuscript.
English language must be improved.
Author Response
Dear editors and reviewers,
On behalf of my co-authors, we thank you very much for giving us an opportunity to re-submit our manuscript, we appreciate editor and reviewers very much for their constructive comments and suggestions on our manuscript entitled “Composite films of polydimethylsiloxane and micro-graphite with tunable optical transmittance.”
We have studied reviewers’ comments carefully and have made revision in the paper. We have tried our best to revise our manuscript according to the comments. Attached please find the revised version, which we would like to submit for your kind consideration.
The main corrections in the paper and the responds to the reviewer’s comments are as following.
Responds to the reviewer’s comments:
Reviewer 1:
The paper reports an interesting study on the fabrication of PDMS composite films with tunable optical transmittance properties. I recommend it for publication after minor revisions.
Generally speaking, the work could have a good scientific soundness but it should be organized in a clearer manner
Comment 1: Some recent articles on the use of nanocarbons in high performance composites should be included in the reference list:
1) doi: 10.3390/polym11050857
2) doi: 10.1021/nn103523t
3) doi: 10.1016/j.cej.2016.09.131
4) doi: 10.1016/j.carbon.2019.04.085
5) doi: 10.1016/j.compscitech.2018.01.008
6) doi: 10.1038/s41598-019-40828-8
7) doi: 10.1016/j.compositesb.2019.03.076
8) doi: 10.1016/j.compositesa.2019.05.008
9) doi: 10.1016/j.snb.2019.03.117
10) doi: 10.1016/j.compscitech.2018.11.003
Response: Thank you very much for your affirmation and advices. The above articles on the use of nanocarbons in high performance composites are interesting and valued, which have been put in the references [11]~[20] and added in lines 25 to 28 of the introduction as following: “Composites, which use of nanocarbons in high performance, have been widely used owing to their strengthening effect , high stiffening and feasible preparation. Recently, graphene oxide-silica nanohybrid[11-16], graphene/polydimethylsiloxane [17,18], polylactic acid (PLA) as a host polymer and different forms of carbon fillers[19,20].”
Comment 2: In the experimental part, the materials and the formulation adopted must be properly presented. The authors should consider the possibility to include a Table reporting codename and formulation of each sample. Raw materials are better described. Amorphous graphite is a microcrystalline graphite. Who was the supplier? Which are the main characteristics of this graphite grade?
Response: Thank you for your comment. In the experiment part, we added the supplier and main characteristics of microcrystalline graphite powder in lines 55-57.
Comment 3: The authors are recommended to divide the experimental section into three subsections:
1) Materials
2) Preparation routes
3) Characterizations
Response: Thank you for your suggestions. The second part of the experiment section has been divided into three subsections：1) Materials. 2) Preparation routes. 3) Characterizations.
Once again, thank you very much for your comments.
We tried our best to improve the manuscript and made some changes in the manuscript according to the comments. We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.
Best regards.
Yours sincerely,
Qi Wang
Reviewer 2 Report
The paper is generally well-written and clear. I have some suggestions to improve its general quality:
- It would be interesting to expand on the applications of PDMS-based composites (as briefly mentioned in the Introduction), and in particular for a composite with the properties the authors have developed (e.g. tunable transmittance, and composites with varying transmittance along its axis);
- How does the dispersion of the graphite powder compare for the different samples?
- Is the almost flat profile of the transmittance over the range of wavelenghts expected? Why was this range selected, and how does it relate to the applications of the composite? How does it compare with the bare PDMS?
- In Figure 5 the shade representing the thickness is confusing as it does not relate with the thickness axis on top; I'd suggest it is removed for clarity.
- The description of the trapezoidal shapes and their stretching is somewhat confusing. It is said that López has run similar experiments with uniform thickness sample and thus could only obtain uniform transmittance even after stretching. Does this mean the authors have run the trapezoidal stretching experiments using a cuneiform sample? Why was this shape chosen? The inset with the trapezoidal shape does not add any value to the figure.
- It's clear that the lenght of the top line of the sample influences the changes in transmittance, but there is no discussion on why this is happening? Likely the differences in geometry lead to thinner samples when the ration between top and base line are bigger. It would also be interesting to have a similar relation with the thickness and the expected transmittance according to the Beer-Lambert law, and perhaps a similar image with the samples over the mulit-coloured USST sheet. A comparison with bare PDMS would also be interesting, if there are any differences at all.
- How does the trasmittance vary in other axis? I think the discussion is important as it's likely that it's affected by geometries and thus might affect how much control there is over this.
Author Response
Dear editors and reviewers,
On behalf of my co-authors, we thank you very much for giving us an opportunity to re-submit our manuscript, we appreciate editor and reviewers very much for their constructive comments and suggestions on our manuscript entitled “Composite films of polydimethylsiloxane and micro-graphite with tunable optical transmittance.”
We have studied reviewers’ comments carefully and have made revision in the paper. We have tried our best to revise our manuscript according to the comments. Attached please find the revised version, which we would like to submit for your kind consideration.
The main corrections in the paper and the responds to the reviewer’s comments are as following.
Responds to the reviewer’s comments:
Reviewer 2:
The paper is generally well-written and clear. I have some suggestions to improve its general quality:
Comment 1: It would be interesting to expand on the applications of PDMS-based composites (as briefly mentioned in the Introduction), and in particular for a composite with the properties the authors have developed (e.g. tunable transmittance, and composites with varying transmittance along its axis);
Response: Thank you for your review. We have added references [11]~[20] in lines 25 to 28 of the introduction as following:
Composites, which use of nanocarbons in high performance, have been widely used owing to their strengthening effect, high stiffening and feasible preparation. Recently, graphene oxide-silica nanohybrid [11-16], graphene/polydimethylsiloxane [17,18], polylactic acid (PLA) as a host polymer and different forms of carbon fillers [19,20].
Comment 2: How does the dispersion of the graphite powder compare for the different samples?
Response: Thank you for your comment. The graphite powder are randomly distributed in the composite films, and there will be slight clustering phenomenon in figure 1(c).
Comment 3: Is the almost flat profile of the transmittance over the range of wavelengths expected? Why was this range selected, and how does it relate to the applications of the composite? How does it compare with the bare PDMS?
Response: The flat transmittance curve in the wavelength range is with our expectation for good spectral neutrality. The reason for choosing the range of 300-1000nm is that the undoped PDSM has good optical transmittance in this wavelength range.
Comment 4: In Figure 5 the shade representing the thickness is confusing as it does not relate with the thickness axis on top; I'd suggest it is removed for clarity.
Response: In Figure 5, the shadow representing thickness has been deleted.
Comment 5: The description of the trapezoidal shapes and their stretching is somewhat confusing. It is said that López has run similar experiments with uniform thickness sample and thus could only obtain uniform transmittance even after stretching. Does this mean the authors have run the trapezoidal stretching experiments using a cuneiform sample? Why was this shape chosen? The inset with the trapezoidal shape does not add any value to the figure.
Response: We cut the thickness-uniform composite film into different trapezoidal samples for tension experiments. We have added relative description in lines 146-147. Isosceles trapezoids are chosen because a transmittance range rather than a single fixed transmittance value of the same sample can be obtained. As a result, the technique can be used more flexibly. We have deleted the trapezoidal shape added in Figure 6 (b).
Comment 6: It's clear that the length of the top line of the sample influences the changes in transmittance, but there is no discussion on why this is happening? Likely the differences in geometry lead to thinner samples when the ration between top and base line are bigger. It would also be interesting to have a similar relation with the thickness and the expected transmittance according to the Beer-Lambert law, and perhaps a similar image with the samples over the multi-colored USST sheet. A comparison with bare PDMS would also be interesting, if there are any differences at all.
Response: Under the same tension conditions, the smaller the length of the upper bottom edge of isosceles trapezoid specimen is, the larger the strain it will be subjected to, so the specimen will be thinner to increase the transmittance. The different trapezoidal samples had similar transmitting phenomenon on multicolor USST paper as shown in Fig. 4. According to the above conclusion, the pure PDMS film will have small tunable range of transmittance.
Comment 7: How does the transmittance vary in other axis? I think the discussion is important as it's likely that it's affected by geometries and thus might affect how much control there is over this.
Response: Thank you for your comment. We measured the transmittance of different trapezoidal samples along the center line and the transmittance at a specific location along the vertical direction to center line was almost uniform. We have given the detailed information of measurement in lines 161-164.
Once again, thank you very much for your comments.
We tried our best to improve the manuscript and made some changes in the manuscript according to the comments. We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.
Best regards.
Yours sincerely,
Qi Wang
Round 2
Reviewer 1 Report
The authors made all the corrections required. The manuscript can be published as it is.
Reviewer 2 Report
Thank you for answering my comments.
