A Comparison of the Performance of Two Kinds of Waterborne Coatings on Bamboo and Bamboo Scrimber

Round 1

Reviewer 1 Report

See my comments in the attached file

Comments for author File: Comments.docx

Author Response

We must thank you for the valuable comments and suggestions, which helped improve our manuscript greatly. Please do forward our heartfelt thanks to the reviewers. Based on the comments we received, careful modifications have been made to the manuscript. All changes were marked in red text. We hope that the revised manuscript answered the questions. Below you will find our point-by-point responses to the comments/ questions:

 

To Reviewer 1:

Lines 2-4:     The title sounds a bit strange and it is not clear. Most probably due to relatively low quality of the English written language. Try with this title, or make something else: “Comparison of performance of two kinds of waterborne coatings on bamboo and bamboo scimber”.

    Thanks. We accepted the advice and have modified the paper title. Please check.

General:       I suggest that you use “waterborne coating” instead of “water-based coating”. The term “waterborne” is much more established in the area of wood coatings than the term “water-based”. This remark should be followed in the whole paper.

Thanks. We accepted the advice and have substituted “waterborne coating” for “water-based coating” in the whole paper. Please check.

General:             The quality of English written level is on a quite low quality level. Sometimes it is even hard to understand what the authors wanted to say. The quality of written language should be substantially improved. I suggest that the help of the professional lector is used.

Thanks. The writing of the paper has been checked, and some words and sentences have been modified. Please check.

Lines 34-36:      Here is an example of the sentence that cannot be understood, presumably due to low quality of English written language: “But the densification of material, less the hydrophilic groups and the parenchyma and fiber filled by adhesive of bamboo scrimber were got simultaneously.” Make this sentence clear. And there is plenty of examples like this one in the text!

Thanks. We have modified the sentence to “However, the substrate with dense structure and less hydrophilic groups was got simultaneously because the parenchyma and fiber were filled by adhesive”. Please check.

Lines 47-48:      this is related to the whole paper: write “polyurethane acrylate” and not “poly urethane acrylate”

Thanks. We accepted the advice and have substituted “polyurethane acrylate” for “poly urethane acrylate” in the whole paper. Please check.

Line 53:             “Phyllostachys pubescens« should be written in italic, as “Phyllostachys pubescens”

Thanks. We have made the modification. Please check.

Table 1:             check – was it “acrylate acid” or “acrylic acid”. Please use the correct version.

Thanks. We have corrected it to “acrylic acid”. Please check.

Lines 61-68:      if I understand the procedure of PUA synthesis, you prepared polyurethane without isocyanates? Is this right, is it possible in your combination of chemicals? Please make a short comment on this fact in the described procedure.

Thanks. We are very sorry for missing of synthesis of polyurethane parts. We added it in the manuscript. “The next step was to graft the pre-polyurethane onto the pre-polyarylate chain. 100 g TDI and 8 g DBTD were dissolved in N-methyl-2-pyrrolidone solvent and blended into a three-neck glass reactor at 150 r min^-1. The reactor was heated to 40 ^oC. During stirring, 66 g HEA was dripped into the reactor within 2 h. The pre-polyurethane emulsion was obtained. Afterwards, both the pre-polyarylate and pre-polyurethane emulsions were mixed in the three-neck glass reactor and blended at 150 r min^-1. The reaction was heated up to 85 ^oC and kept for 2 h.” Please check.

Lines 100, 105: The standards ISO are mentioned. All three standards should be listed in the list of references, just like all other references

Thanks. We have added the related references and reset the references numbers. Please check.

Lines 124-137:   there is plenty of assignments of the bands in the spectra to certain vibration. Please add necessary references to support these assignments

Thanks. We have added the related reference 28. Please check.

General:            in FT-IR we commonly use the term “band” instead of the term “peak”. So, please change “peak” into “band” elsewhere in this paper

Thanks. We accepted the advice and have substituted “band” for “peak” in the whole paper. Please check.

Lines 124-137: you say that there were chemical reactions. Chemical reactions happened when? During preparation of the scrimber? Make this clear. And these are all presumptions – might be true, or the changes might be the consequence of added chemicals during bonding and also the reactions between bamboo and adhesive might have occurred. Make a comment on these possibilities. Also, you wrote: “Compared with bamboo, the absorption peaks of –OH at 85500px^-1 of BS was obviously weakened, which indicated that the hydrophilicity of BS decreased.”. My comment: not necessarily.

Thanks. The chemical reactions happened during the preparation of the bamboo scrimber. We have added it in the manuscript. The reaction was inferred by Meng et al. 2018, we added the related reference 11. Besides, we accepted the advice of deleting the comparison at 3420 cm^-1. Please check.

Lines 138-147:   support assignment of the bands by citing relevant literature!

Thanks. We have added the related references 28 and 29. Please check.

Lines 148-160:  support assignment of the bands by citing relevant literature!

Thanks. We have added the related references 28 and 30. Please check.

 

Sincerely,

Jianfeng Xu, Ru Liu, Huagui Wu, Hongyun Qiu, Yanglun Yu Ling Long, Yonghao Ni

 

25 Jan, 2019

Author Response File: Author Response.pdf

Reviewer 2 Report

Please let an English native speaker check the grammar. Too many sentences start with "And.....", word order in some sentences, the use of "the", plural s, tenses, prepositions etc. must be checked and corrected through out the text.

L2 Title: change to "...coating performance on bamboo..."

L11: what was the contribution of the other four authors?

L19: delete "bamboo coated by" because only the coating has adhesion to the substrate, which is bamboo

L48: what do you mean with coating mechanism, could you find another wording here?

L54: I think the Fujian province is IN THE south east of China

L62 ff: r/min is not a SI unit, please change to min-1

L68+L77: please add: PROTECTED against light

L78 ff: please add a descpription how neat bamboo was prepared before coating

2.4 Coating: Why was a photoinitiator formulatied into the PUA when there was no UV curing?

2.5.: describe the standard methods briefly with a few words. in particular the adhesions levels you use in the results section must be described

L107: I didn´t see the abreviation HBS earlier in the text, what do you mean?

L111: the results from XPS analysis are nto the number of functioinal groups, it may be dominant functional groups or similar you measure with the spectra

L128: ATR-FTIR does not allow conclusions on hydrophilicity of a surface, the sample may shave imply been dryier

L154: you have not shown evidence on better or worse penetration of the coatings, at least not with FT-IR

L174ff: the statements on reactions are rather speculative, film thicknesses of the coatings an penetration depths of the analysis may be another reason for your findings; please discuss the influence of the depths of detection of XPS vs. film thickness on your samples

Table 2 caption: add "XPS analysis"

Fig 2 caption: add "XPS analysis"

L207: add: ...After the recombinant processing INTO BS....

L212: conclusions on penetrations are speculative; you would need to analyse cross sections of samples

Fig3: bubbles and agglomerates cannot be seen on the images; please add at least arrows or markers on the images

Fig 4: please add a SI unit for roughness and explain this value in the method description; uncoated bamboo is not shown here

Fig 5: please add a table with results of the adhesion measurements

Table 4: I suggest to add a few colums e.g. for dry film thickness, adhesion, roughness

Talbe 4: how do you explain the much higher abrasion value in the last line? A discussion on hardness and abrasion results is missing

L246: you seemingly forgot to mention which coating was better; a conclusion on better penetration, however, is rather speculative

Author Response

We must thank you for the valuable comments and suggestions, which helped improve our manuscript greatly. Please do forward our heartfelt thanks to the reviewers. Based on the comments we received, careful modifications have been made to the manuscript. All changes were marked in red text. We hope that the revised manuscript answered the questions. Below you will find our point-by-point responses to the comments/ questions:

 

To Reviewer 2:

L2 Title: change to "...coating performance on bamboo..."

Thanks. We accepted the advice and have modified the paper title. Please check.

L11: what was the contribution of the other four authors?

    Thanks. The research about the paper was made by a team including the other five authors, who came from different departments and undertook different tasks. We had showed the details in “Author Contributions”. Please check.

L19: delete "bamboo coated by" because only the coating has adhesion to the substrate, which is bamboo

Thanks. We have modified the sentence to “The epoxy resin coating on bamboo has the best adhesion”. Please check.

L48: what do you mean with coating mechanism, could you find another wording here?

Thanks. In the original paper, “coating mechanism” means the physical and chemical changes of the substrates. And the “coating performance” can contain this meaning, so we have deleted the short sentence “and the coating mechanism”. Please check.

L54: I think the Fujian province is IN THE south east of China

Thanks. We have deleted the word “southeast”. Please check.

L62 ff: r/min is not a SI unit, please change to min-1

Thanks. We have made the changes in the whole paper. Please check.

L68+L77: please add: PROTECTED against light

Thanks. We have added protected in the manuscript. Please check.

L78 ff: please add a descpription how neat bamboo was prepared before coating

Thanks. We have added the preparation of neat bamboo. “The neat bamboo, which was designed as the control group, was prepared by removal of inner and out nodes of bamboo tube, and cut into dimension of 2600 mm × 35 mm × 5 mm.”

2.4 Coating: Why was a photoinitiator formulatied into the PUA when there was no

UV curing?

Thanks. We are sorry for making a mistake for the formulation. The photoinitiator was deleted.

2.5.: describe the standard methods briefly with a few words. in particular the adhesions levels you use in the results section must be described

Thanks. We have added the description of the adhesions levels in 2.5. Please check. “The adhesion level was determined by a cross-cut test of 0-5 classification. Classification 0: the edges of the cuts are completely smooth; none of the squares of the lattice is detached. Classification 1: detachment of small flakes of the coating at the inter sections of the cuts. A cross-cut area not greater than 5% is affected. Classification 2: the coating has flaked along the edges and/or at the intersections of the cuts. A cross-cut area greater than 5%, but not greater than 15%, is affected. Classification 3: the coating has flaked along the edges of the cuts partly or wholly in large ribbons, and/or it has flaked partly or wholly on different parts of the squares. A cross-cut area greater than 15%, but not greater than 35%, is affected. Classification 4: The coating has flaked along the edges of the cuts in large ribbons and/or some squares have detached partly or wholly. A cross-cut area greater than 35%, but not greater than 65% is affected. Classification 5: Any degree of flaking that cannot even be classified by classification 4.”

L107: I didn´t see the abreviation HBS earlier in the text, what do you mean?

Thanks. It is a spelling mistake and we have deleted the word. Please check.

L111: the results from XPS analysis are not the number of functioinal groups, it may be dominant functional groups or similar you measure with the spectra

Thanks. We have corrected it the dominant functional groups. Please check.

L128: ATR-FTIR does not allow conclusions on hydrophilicity of a surface, the sample may shave imply been dryier

Thanks. We have deleted the description of the hydrophilicity. Please check.

L154: you have not shown evidence on better or worse penetration of the coatings, at

least not with FT-IR

Thanks. The penetration of the coatings was not discussed in this paper and we will make some relevant research in the future. Thank you for the advice.

L174ff: the statements on reactions are rather speculative, film thicknesses of the coatings an penetration depths of the analysis may be another reason for your findings; please discuss the influence of the depths of detection of XPS vs. film thickness on your samples

Thanks. We have added the film thickness measurement in our manuscript. And we also corrected the analysis of XPS results. “Another possible reason might be associated with the film thickness (Table 4), the BS coated by PUA showed larger film thickness than bamboo coated with PUA, indicating the difficulty for PUA penetrating into BS. Therefore, the N content was higher.” And “Also, the larger film thickness of epoxy resin coated BS contributed to the larger O content.” Please check.

Table 2 caption: add "XPS analysis"

Thanks. We have added the words in Table 2 caption. Please check.

Fig 2 caption: add "XPS analysis"

Thanks. We have added the words in Fig. 2 caption. Please check.

L207: add: ...After the recombinant processing INTO BS....

Thanks. We have added it. Please check.

L212: conclusions on penetrations are speculative; you would need to analyse cross

sections of samples

Thanks. We have observed the cross sections for the SEM analyse. However, due to the very thin film layer, it was very hard to understand the penetration. But we added the film thickness for the coated groups. We think it could be helpful to understand the penetration depth. Please check.

Fig3: bubbles and agglomerates cannot be seen on the images; please add at least

arrows or markers on the images

Thanks. We have added the arrows on the images. Please check.

Fig 4: please add a SI unit for roughness and explain this value in the method description; uncoated bamboo is not shown here

Thanks. We added the unit of “nm” for the roughness. Please check. The surface of uncoated bamboo and bamboo scrimber was very rough, and the micro-gaps of bamboo cell walls could break the scanning probe of the AFM test, which made it untestable.

Fig 5: please add a table with results of the adhesion measurements

Thanks. We added a brief description for the adhesion measurement in line 112. “The adhesion level was determined by a cross-cut test of 0-5 classification. Classification 0: the edges of the cuts are completely smooth; none of the squares of the lattice is detached. Classification 1: detachment of small flakes of the coating at the inter sections of the cuts. A cross-cut area not greater than 5% is affected. Classification 2: the coating has flaked along the edges and/or at the intersections of the cuts. A cross-cut area greater than 5%, but not greater than 15%, is affected. Classification 3: the coating has flaked along the edges of the cuts partly or wholly in large ribbons, and/or it has flaked partly or wholly on different parts of the squares. A cross-cut area greater than 15%, but not greater than 35%, is affected. Classification 4: The coating has flaked along the edges of the cuts in large ribbons and/or some squares have detached partly or wholly. A cross-cut area greater than 35%, but not greater than 65% is affected. Classification 5: Any degree of flaking that cannot even be classified by classification 4.” Please check.

Table 4: I suggest to add a few colums e.g. for dry film thickness, adhesion,

roughness

Thanks. We have added dry film thickness and adhesion level, and roughness in Table 4. Please check.

Talbe 4: how do you explain the much higher abrasion value in the last line? A

discussion on hardness and abrasion results is missing

Thanks. We have added discussion for it. “However, the abrasion value of BS coated by epoxy coating was the highest, which might be associated with the high film thickness and roughness. It was mentioned in the SEM analysis that more bubbles were found on the surface of the BS coated with epoxy coating. Thus, the surface performance of it was poor.” Please check.

L246: you seemingly forgot to mention which coating was better; a conclusion on better penetration, however, is rather speculative

Thanks. We have added the penetration in the conclusion. “However, the PUA coated samples owned smoother surfaces with adhesion level of 2, pencil hardness of H. Besides, the abrasion value of PUA coated samples was acceptable in range of 0.088-0.092 g/100r for its rarely good penetration.” Please check.

 

Sincerely yours,

 

Jan 25, 2019

 

Jianfeng Xu, Ru Liu, Huagui Wu, Hongyun Qiu, Yanglun Yu, Ling Long, Yonghao Ni

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Thank you for following my comments from the 1st Review round. By majority it is OK now. However, the quality of English written language can still be improved. I guess this can be done by the publisher prior sending the manuscript for printing. For instance, I suggested you to correct the sentence: “But the densification of material, less the hydrophilic groups and the parenchyma and fiber filled by adhesive of bamboo scrimber were got simultaneously.” You changed it into "“However, the substrate with dense structure and less hydrophilic groups was got simultaneously because the parenchyma and fiber were filled by adhesive”. However, this sentence is still not OK. I do not understand the meaning of "was got simultaneously". PLease make this clear!

Author Response

We must thank you for the valuable comments and suggestions, which helped improve our manuscript greatly. Based on the comments we received, careful modifications have been made to the manuscript. All changes were marked in red text. We hope that the revised manuscript answered the questions. Below you will find our point-by-point responses to the comments/ questions:

 

To Reviewer 1:

 

Thank you for following my comments from the 1st Review round. By majority it is OK now. However, the quality of English written language can still be improved. I guess this can be done by the publisher prior sending the manuscript for printing. For instance, I suggested you to correct the sentence: “But the densification of material, less the hydrophilic groups and the parenchyma and fiber filled by adhesive of bamboo scrimber were got simultaneously.” You changed it into "“However, the substrate with dense structure and less hydrophilic groups was got simultaneously because the parenchyma and fiber were filled by adhesive”. However, this sentence is still not OK. I do not understand the meaning of "was got simultaneously". PLease make this clear!

Thanks. We have changed this sentence to “However, the dense structure and less hydrophilic groups are gotten because the parenchyma and bamboo fiber were compressed and filled by adhesive.” Please check.

 

Sincerely yours,

 

Jianfeng Xu, Ru Liu, Huagui Wu, Hongyun Qiu, Yanglun Yu, Ling Long, and Yonghao Ni

 

Feb 9, 2019

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript has improved significantly. A few editorial comments are marked in the attachted document.

2.2: r ist not a SI unit but rotations have the unit [1], so the rotation speed of the reactor must be stated in min-1 only

L186 - L221: with all the interpretation made in this chapter it is very important to know the depths  of detection achieved with this kind of analysis. Did it reach the substrate?

L175, L238, L279: any interpretation of penetration or permeability is speculative because the methods used did not give evidence on this. Please avoid this.

L290: Please add the contribution of the new co-author Yonghao Ni.

Comments for author File: Comments.pdf

Author Response

We must thank you for the valuable comments and suggestions, which helped improve our manuscript greatly. Based on the comments we received, careful modifications have been made to the manuscript. All changes were marked in red text. We hope that the revised manuscript answered the questions. Below you will find our point-by-point responses to the comments/ questions:

 

To Reviewer 2:

The manuscript has improved significantly. A few editorial comments are marked in the attachted document.

Thanks. We have corrected the manuscript according to the attached file.

2.2: r ist not a SI unit but rotations have the unit [1], so the rotation speed of the reactor must be stated in min-1 only

Thanks. We have deleted the unit of r.

L186 - L221: with all the interpretation made in this chapter it is very important to know the depths of detection achieved with this kind of analysis. Did it reach the substrate?

Thanks. The depth of XPS analysis is about 2 nm, which is much lower than the thickness of the coating. However, if the substrate was not well covered, some element of the substrate might be detected.

L175, L238, L279: any interpretation of penetration or permeability is speculative because the methods used did not give evidence on this. Please avoid this.

Thanks. We have deleted the penetration or permeability.

L290: Please add the contribution of the new co-author Yonghao Ni.

Thanks. We added the contribution for Yonghao Ni that Writing-Review & Editing, Yonghao Ni.

 

Sincerely yours,

 

Jianfeng Xu, Ru Liu, Huagui Wu, Hongyun Qiu, Yanglun Yu, Ling Long, and Yonghao Ni

 

Feb 9, 2019