Influence of Phenylmethylsilicone Oil on Anti-Fouling and Drag-Reduction Performance of Silicone Composite Coatings
Round 1
Reviewer 1 Report
The paper presents the issue regarding the anti-fouling and reducing the drag properties of paint coatings. The additives were investigated in relation to coatings functional properties (mechanical, physical and bacteria related properties ect).
Overall the paper is well written, the title refers to the aim of the work. The introduction justifies the idea of the work. The methodology is properly used. On the other hand, the discussion and analysis of the results do not convince me and Authors should explain the "initial roughness effect", see comments below.
My comments on, especially, the analysis of the results.
1) Please analyse the effect of initial coatings surface roughness on all tested properties. It should be done.
All we know, that the surface roughness is the primary parameters which affect most of the paint functional properties. From my point of view, the paper should present the initial surface roughness (before testing) - provide the results. Then the roughness results should be discussed with the properties of the all tested coating. I am worried that the differences in initial surface roughness of coatings are much more crucial than the additive. Please discuss it in the paper and explain it to me.
2) The coatings thickness should be stated. Please add it.
3) Please explain how the coatings were deposited. Now, it is only written in caption of fig. 2 that "The spraying...." - please provide some details about the fabrication procedure.
Author Response
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Influence of phenylmethylsilicone oil on anti-fouling and drag-reduction performance of silicone composite coatings” (ID: coatings-1028957). These comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have revised the full text. The language of this manuscript has been reviewed by a technical editor. Revised portion is marked using the “Track Changes” function in Microsoft Word. The responses to your comments are as follows.
The discussion and analysis of the results do not convince me and Authors should explain the "initial roughness effect", see comments below.
Comments 1. Please analyse the effect of initial coatings surface roughness on all tested properties. It should be done.
Response:
The surface roughness of the coating is the primary parameters which affect most of the paint functional properties. The required coating is prepared by spraying technics. The roughness of the coating was tested by Olympus OLS4000 CLSM (OLYMPUS (China) Co., Ltd., Beijing, China), and the specific results were shown in Figure 1.
|
Coating |
Roughness (Ra) |
|
W-0 |
|
|
B30-3 |
|
|
B30-5 |
|
|
B30-7 |
|
|
B30-9 |
|
|
B75-9 |
|
|
B100-9 |
Figure 1. Initial coatings surface roughness
It is found that the initial roughness of all coatings is approximately the same. Roughness will not be used as a variable to affect other properties of the coating.
Comments 2. The coatings thickness should be stated. Please add it.
Response:
Figure 2. The spraying sequence of composite coatings.
The thickness of epoxy primer, epoxy intermediate paint, silicone connecting paint and silicone topcoat were 80, 80, 60 and 150 μm, respectively .
Authors revised the manuscript. Please find in revised manuscript.
Comment 3. Please explain how the coatings were deposited. Now, it is only written in caption of fig. 2 that "The spraying...." - please provide some details about the fabrication procedure.
Response:
The spraying process was shown in Figure 3. The viscosity of the paint was controlled between 14 and 17 seconds (measured with No. 4 Cup).
Figure 3. Spraying process of silicone topcoat.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors report the influence of phenylmethylsilicone oil on anti-fouling and drag-reduction performance of silicone composite coatings. The manuscript needs extensive revisions before publication. I would like the authors to carefully review the following comments to improve the overall quality of the manuscript.
1- There are serious grammatical and structural errors that need to be rectified for publication. Check the paper with a linguistic expert of with the MDPI English editing service.
2- Clearly explain the novelty of this work in the abstract or the introduction section.
3- The reported literature is not suffice. Cite some more, rather most recent, literature for readers' understanding and provide a comparative analysis with the present study.
4- Introduction section only presents the literature review and the previous papers published on the research topic. I want the authors to relate the previous literature on why the present research was required and how it would revolutionize the subject topic. Also, briefly explain the most important results in the last paragraph of introduction section.
5- Provide CAS numbers of all the chemicals and coating materials.
6- There are too many Figures involved (16 figures). I want the authors to reduce the number of Figures because it only complicate the explanation process. For example, Figure 3 is not necessary for the explanation of a simple process. Also, I recommend the authors to merge some of the individual figures into multiple parts, such as merging figures 12 and 13, rather than using a whole new figure.
7- The results are explanatory rather argumentative. The authors are reporting simple narration of facts rather than propounding the analogy of why there results are better than the reported previous literature? Also, more refined scientific reasoning is required with proper referencing.
Author Response
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Influence of phenylmethylsilicone oil on anti-fouling and drag-reduction performance of silicone composite coatings” (ID: coatings-1028957). These comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have revised the full text. The language of this manuscript has been reviewed by a technical editor. Revised portion is marked using the “Track Changes” function in Microsoft Word. The responses to your comments are as follows.
1- There are serious grammatical and structural errors that need to be rectified for publication. Check the paper with a linguistic expert of with the MDPI English editing service.
Response:
The grammatical and structural of this manuscript has been reviewed by a technical editor.
2- Clearly explain the novelty of this work in the abstract or the introduction section.
Response:
Authors revised the manuscript. Please find in revised manuscript.
In this paper, phenyl silicone oils of different molecular weights are added to the silicone coating by means of mechanical stirring. To study drag reduction performance of silicone coating, the water contact angle, surface energy and elastic modulus of PSO were measured.
3- The reported literature is not suffice. Cite some more, rather most recent, literature for readers' understanding and provide a comparative analysis with the present study.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
4- Introduction section only presents the literature review and the previous papers published on the research topic. I want the authors to relate the previous literature on why the present research was required and how it would revolutionize the subject topic. Also, briefly explain the most important results in the last paragraph of introduction section.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
5- Provide CAS numbers of all the chemicals and coating materials.
Response: Those numbers were added in revised manuscript.
polydimethylsiloxane CAS Number: 31900-57-9
Phenylmethylsilicone oil CAS Number: 63148-58-3
Tetraethylorthosilicate CAS Number:68412-37-3
Dibutyltin dilaurate CAS Number:77-58-7
6- There are too many Figures involved (16 figures). I want the authors to reduce the number of Figures because it only complicate the explanation process. For example, Figure 3 is not necessary for the explanation of a simple process. Also, I recommend the authors to merge some of the individual figures into multiple parts, such as merging figures 12 and 13, rather than using a whole new figure.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
7- The results are explanatory rather argumentative. The authors are reporting simple narration of facts rather than propounding the analogy of why there results are better than the reported previous literature? Also, more refined scientific reasoning is required with proper referencing.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
Author Response File: Author Response.pdf
Reviewer 3 Report
Too many references from Chine and there are a few from USA or Europe. The people working there are several. Please make better the introduction.
Author Contributions: reduce the names to three….the concepts in the MDPI format is a suggestion, not an obligation.
Conclusions: give 2-4 as bullets, one per each highlight.
The experimental attachment bacteria were selected from the natural seawater of Dalian Yellow Sea: are there big differences with other seas…please explain the reasons. Navicula Tenera is not common in other places?
I have read carefully and results is OK. The application is some unclear….propeller?. Please define.
How did you carry out the medium environment, some people gave very interest to test tracebility, see and include Biomachining: Preservation of Acidithiobacillus ferrooxidans and treatment of the liquid residue, Engineering in Life Sciences 17 (4), 382-391 and Critical reviews in biotechnology 37 (3), 323-332they considered a kind of bacteria aggressive qith some ship components.
Good work, please improve it a little
Author Response
Dear Reviewer:
Thank you for your comments concerning our manuscript entitled “Influence of phenylmethylsilicone oil on anti-fouling and drag-reduction performance of silicone composite coatings” (ID: coatings-1028957). These comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have revised the full text. The language of this manuscript has been reviewed by a technical editor. Revised portion is marked using the “Track Changes” function in Microsoft Word. The responses to your comments are as follows.
- Too many references from Chine and there are a few from USA or Europe. The people working there are several. Please make better the introduction.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
- Conclusions: give 2-4 as bullets, one per each highlight.
Response:
Authors agreed with the comments of reviewer and revised the manuscript. Please find in revised manuscript.
- The experimental attachment bacteria were selected from the natural seawater of Dalian Yellow Sea: are there big differences with other seas…please explain the reasons. Navicula Tenera is not common in other places?
Response:
(1). My university is located in Dalian, so I choose the sea water of Dalian Yellow Sea. Seawater in other sea areas can be selected.
(2) Navicula Tenera is one of the most common Benthic diatoms in the ocean around the world.
- I have read carefully and results is OK. The application is some unclear….propeller?. Please define.
Response:
The coating prepared is mainly applied to the surface of the shipping, not only the propeller. I would do more research in the future.
5.How did you carry out the medium environment, some people gave very interest to test tracebility, see and include Biomachining: Preservation of Acidithiobacillus ferrooxidans and treatment of the liquid residue, Engineering in Life Sciences 17 (4), 382-391 and Critical reviews in biotechnology 37 (3), 323-332they considered a kind of bacteria aggressive qith some ship components.
Response:
The paper you introduced helps me a lot.
The preparation process of the medium environment used in the bacterial attachment experiment is as follows:
Before the test, the measuring cylinders, beakers, cotton swabs, and sterile seawater were sterilized by YX-280D portable sterilizing equipment (Hefei Huatai Medical Equipment Co., Ltd., Hefei, China) under a high pressure of 0.1 MPa for 20 min. Then placed on the SW-CJ-1FD clean bench (Shanghai Boxun Industrial Co., Ltd., Shanghai, China) and sterilized by UV light for 20 min. Immersed six coated glass slides of each formula in natural seawater. Three coated slides of each formula were taken as group P, and unattached bacteria on the surface were rinsed away with sterile seawater. The other 3 coated slides of each formula were group Q, put into a 50 mL centrifuge tube, and was filled 40 mL of sterile seawater. HY-4 Variable-speed multi-function shaker (Guohua Electric Co., Ltd., Changzhou, China) was used to simulate seawater washing the surface of the sample for 15 min under an oscillation amplitude of 20 mm and frequency of 130 r/min to removed bacteria that were not firmly attached to the surface, and then brushed the bacteria on the surface of the two samples into sterile seawater with a cotton swab. And sterilized seawater was used to dilute the bacteria suspension to a volume of 10-6. Take 10 μL from it and inoculate it on 2216E solid medium, and spread evenly. The medium was then inverted and cultured in a biochemical incubator at (18±1) °C for two days. Take pictures to record the experimental results. Perform grayscale processing on photos to increase contrast. The image-Pro Plus software was used to count and process the bright area of the processed image to quantitatively analyze the colonies.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Dear Authors,
Thank you for your explanations, I accept them all. It is interesting that the roughness is at a constant level.
I have one minor comment on the description in fig 2. Figure 2. Spraying process of silicone topcoat - please improve the legend font size and the quality of the figure.
Wishes,
Reviewer
Author Response
Response:
The spraying process was shown in Figure 2.
Figure 2. Spraying process of silicone topcoat.
Reviewer 2 Report
The authors have significantly provided the response to the comments asked in the review round 1. I believe the article is now ready for publication in coatings.
Author Response
Response:
The grammatical and structural of this manuscript has been reviewed by a technical editor.
