Ubim Fiber (Geonoma baculífera): A Less Known Brazilian Amazon Natural Fiber for Engineering Applications

Round 1

Reviewer 1 Report

The contribution of the document regards the new source of fillers/filaments, this plant. As far as the characterization methods of the samples it is ok, but as for the discussion and correlation of the results with the chemistry/structure/nature of the samples, the paper need to be improved.

Author Response

The authors would like to thank the Reviewers for the valuable comments and suggestions on the structure and scientific aspects that contribute to improve the manuscript. Amendments are provided accordingly. Responses to each comment are listed below and all modifications/additions were marked as Track Changes in the revised version of the manuscript.

General comment: The contribution of the document regards the new source of fillers/filaments, this plant. As far as the characterization methods of the samples it is ok, but as for the discussion and correlation of the results with the chemistry/structure/nature of the samples, the paper need to be improved

Response: The authors thank the reviewer for suggestions to improve our manuscript the new revised version in now substantially improved in terms of discussion and results correlation with the chemistry, structure and nature of samples.

Author Response File: Author Response.pdf

Reviewer 2 Report

The submitted manuscript is currently not ready for publication. Authors should pay more attention to the literature review. Review the obtained results of structural studies. Answer the question how the minimum density values ​​relate to high crystallinity. Expand the discussion in all sections. After that, revise the conclusions.     Lines 62, 63. Not quite the correct expression. Cellulose contains both crystalline and amorphous fractions. 2. Materials and Methods. For the obtained samples, it is necessary to indicate the content of the alpha fraction of cellulose, lignin, water, metals, etc. Line 154. "cave" needs to be changed to "Cave". 2.2.1. Crystallinity index (CI). How can the peak in the diffractogram be associated with the amor phase? What shooting method did the authors use? The sections devoted to the determination of fiber density should be expanded with discussion. How do the authors explain such a spread in values? Is it correct to compare different types of density with each other? If we talk about cellulose, then for it the most common density values ​​are 1.5 g / cm³ (https://doi.org/10.1007/s10692-017-9786-x). And as you know, cellulose contains both crystalline and amorphous phases. How do the authors explain such high density values ​​- 1.8604 ± 0.2596 g / cm³?  

Author Response

The authors would like to thank the Reviewers for the valuable comments and suggestions on the structure and scientific aspects that contribute to improve the manuscript. Amendments are provided accordingly. Responses to each comment are listed below and all modifications/additions were marked as Track Changes in the revised version of the manuscript.

 General comment: The submitted manuscript is currently not ready for publication. Authors should pay more attention to the literature review. 


 Response: The authors agree with the Reviewer that our manuscript needs improvements in order to be ready for publication. In particular, more attention is now payed to recent literature review.

Point 1: Review the obtained results of structural studies. 


Response: As recommended, a thorough revision was performed on the obtained structural results of discussed studies.

 

Point 2: Answer the question how the minimum density values relate to high crystallinity. 


 

Response: The values of density and crystallinity of natural fibers are now considered in Table 2 and discussed, which contribute to answer the question of how minimum density relates to high crystallinity.

 

Point 3: Expand the discussion in all sections. After that, revise the conclusions. 


 

Response: Complied; discussion related to density and crystallinity is now expanded and conclusion are revised accordingly.

 

Point 4: Lines 62, 63. Not quite the correct expression. Cellulose contains both crystalline and amorphous fractions. 


 

Response: The Reviewer is right and the indicated correction is now introduced in the revised version.

 

Point 5: 2. Materials and Methods. For the obtained samples, it is necessary to indicate the content of the alpha fraction of cellulose, lignin, water, metals, etc. 


 

Response: The requested contents are now indicated in the revised version.

 

Point 6: Line 154. "cave" needs to be changed to "Cave". 


 

Response: Complied, now is by Cave [26]

 

Point 7: 2.2.1. Crystallinity index (CI). How can the peak in the diffractogram be associated with the amor phase? 


 

Response: The Reviewer raised a relevant question, which is now better explained in the corresponding section.

 

Point 8: What shooting method did the authors use? 


 

Response: The authors apologize for lack of information on shooting methods that are now fully disclosed in the revised version.

 

 

Point 9: The sections devoted to the determination of fiber density should be expanded with discussion. 


 

Response: As recommended, sections 3.1.1; 3.1.2; and 3.1.3 are now expanded and discussed in the revised version.

 

Point 10: How do the authors explain such a spread in values? 


 

Response: This is another important question, which is particularly explained and discussed in the revised version.

 

Point 11: Is it correct to compare different types of density with each other? 


 

Response: The answer to this question is now presented as a relevant point and discussed in the revised version.

 

Point 12: If we talk about cellulose, then for it the most common density values are 1.5 g / cm³ (https://doi.org/10.1007/s10692-017-9786-x). And as you know, cellulose contains both crystalline and amorphous phases. How do the authors explain such high density values - 1.8604 ± 0.2596 g / cm³?  


 

Response: First, the authors are thankful to the suggested paper that serves to clear the discussed relevant points on natural fiber cellulose content. Second, the high density obtained by the pycnometry technique is now confronted with the other techniques for a possible explanation, based on result of another Amazon natural fiber and pure cellulose.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Line 73. "a polysaccharide (not a form of cellulose)," - extra information. Better to remove. 2.2. Crystallinity index (CI). I recommend indicating the angular position of the peak corresponding to the crystalline phase and the intensity corresponding to the amorphous phase. For the amorphous phase, there are no clear peaks in the diffraction patterns.   Lines 191-193. You need to add a link. In my opinion, it is better to delete this statement. Other methods are usually used to determine the alpha fraction. Lines 260, 261. "and did not correspond to any data already mentioned in the literature, and, therefore, it was not used as another constituent of the ubim fiber." - I suggest deleting. Lines 269-272. It is better to remove this information from this section. Line 360. "0.703" - you can round the density value.

Author Response

Response to Reviewer 2 – Round 2 Comments

The author would like to thank the Reviewer for the additional valuable comments and suggestions.

 Point 1: Line 73. "a polysaccharide (not a form of cellulose)," - extra information. Better to remove. 


Response: Complied, this extra information is now removed from the second revised version.

 

Point 2: 2.2. Crystallinity index (CI). I recommend indicating the angular position of the peak corresponding to the crystalline phase and the intensity corresponding to the amorphous phase. For the amorphous phase, there are no clear peaks in the diffraction patterns. 


Response: As recommended, the angular position of the peaks corresponding to the crystalline phase and the halo of the amorphous phase, obtained from convoluted XRD patters in Figure 4, as well as the respective intensities are now indicated in a new additional text.

 

Point 3: Lines 191-193. You need to add a link. In my opinion, it is better to delete this statement. Other methods are usually used to determine the alpha fraction. 


Response: The authors agree with the suggestions and the statement in lines 191-193 is now deleted.

 

Point 4: Lines 260, 261. "and did not correspond to any data already mentioned in the literature, and, therefore, it was not used as another constituent of the ubim fiber." - I suggest deleting. 


Response: Deleted, as suggested by the Reviewer.

 

Point 5: Lines 269-272. It is better to remove this information from this section. 


Response: As requested, the information in lines 269-272 is now removed in the second revised version.

 

Point 6: Line 360. "0.703" - you can round the density value. 


Response: As recommended, the value is now rounded to “0.70 g/cm³”.

Author Response File: Author Response.pdf