Effect of Abiotic Treatments on Agricultural Plastic Waste: Efficiency of the Degradation Processes

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Your manuscript provides valuable insights into the degradation of plastics used in agriculture, which is a significant area of research. However, I have a few suggestions that could enhance the clarity and impact of your work:

1. Abstract: The abstract would benefit from a brief explanation of the research background and motivation. Consider adding a sentence or two about why studying the degradation of these specific plastics is important, and its potential significance in environmental protection or agriculture.

2. While the abstract mentions that photo-oxidation treatments are more effective and cost-efficient than thermochemical treatments, it lacks details on how different treatments affect different types of plastics. Briefly mentioning the most effective treatment for each type of plastic would add persuasiveness to the abstract.

3.     The introduction provides necessary background information, yet further strengthening could be achieved by more explicitly stating the research motivation, objectives, innovation, and expected contributions. This would better capture the reader’s interest and clearly demonstrate the study’s value and importance.

4.     Materials Detail: The detailed information on all materials used, such as types, models, molecular weights, etc., is missing. Providing these details would enhance the reproducibility and technical understanding of your study.

5.     Equipment Details in Photo-oxidation UV Treatments: The model, manufacturer, and place of production of the equipment used for UV pre-treatments should be included to allow for replication of your study and to provide complete technical context.

I believe addressing these points will significantly improve the manuscript and more clearly convey your valuable findings to the scientific community.

Author Response

Please find attached the author's reply to review document.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This work is focused on the effect of abiotic pre-treatments on the plastic polymers degradation. The relevance of such research is increasing every year, as is the industry's need for new efficient approaches to plastic degradation due to increasing of different types of polymers produce and consumption. In addition, there is a need to conduct further research using a combination of the most effective abiotic methods from this study with microbial degradation of plastic to its final decomposition.

The text of the manuscript is well written, the results are presented clearly, and overall the work is interesting.

But the manuscript needs a minor revision before publication.

Please consider my comments as listed below.

Comments

Introduction

I recommend adding a short paragraph about biological methods of plastic degradation, their effectiveness, and the possibility of combined use with abiotic methods. Add also some references to works in this area.

Line 72 “…results in the break of specific chemical bonds into de polymer structure…” possibly a typo and correct “into the polymer structure”

Materials and methods

Line 120 2.2.3. Processing conditions to enhance polymer degradation - this is probably point 2.2.

Results

Supplementary materials 

Figure S1 and Figure S2 correct caption to pictures: remove  “(figure above)” and “(figure below)” since this information does not correspond to the data presented in the figures.

Figure S1. Why are two identical images presented?

Figure 6. Two identical figures are shown under the designation (a) with the same Carbonyl index value

Conclusions

Line 405 “…Regarding the thermochemical pre-treatments… possibly an incomplete sentence

References

The references part must be written according to the requirements of the journal, where the year of publication is put in its correct place and with the correct italics and bold font style.

Author Response

Please find attached the author´s reply to the review report

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The authors present “Effect of abiotic treatments on agricultural plastic waste: efficiency of the degradation processes”. However, it should be revised before it can be published.

1)      The abstract could benefit from a clearer elucidation of the outcomes associated with the presented polymers. A more explicit and detailed mention of the polymer results is needed to enhance the overall clarity and comprehensibility of the abstract.

2)      In the literature, there are many works that study the degradation of PS and PE (Low-density PE (LDPE) and Linear Low-density PE 104 (LLDPE)), as well as PET. These references must be presented. What else does the manuscript offer in this area? I suggest the authors better define the goal of their work and clearly state the results and the final message of the paper. Therefore, what is the innovative part of this work? The introduction should be adjusted accordingly.

3)      Why did the authors choose not to perform TGA measurements in ambient air, especially considering their intention to draw comparisons with photo-oxidation measurements? To enhance the clarity and completeness of the study, it is recommended that Figure S1 includes all the Thermogravimetric Analysis (TGA) curves for a comprehensive presentation of the data. This addition would contribute to a more thorough understanding of the experimental results.

4)      Why did the authors choose to employ these oxidizing agents to study the thermochemical pre-treatments? What is the error bar of these measurements?

5)      Figure S2 does not present pareto charts in line 236. Figure S5- S12 should be mentioned in the revised manuscript. The authors are required to elucidate the observed increase in mass illustrated in Figures S5, S6, S8 and S9 particularly beyond 500°C. Additionally, there is an increase exceeding 100% observed in certain TGA curves, especially at the onset of the plots. Have they performed a calibration on the instrument?

6)      Line 293: All the figures number should be checked.

7)      Figure 6 displays a consistent carbonyl index across all time points examined for both UV-B and UV-C. This observation requires clarification and explanation.

Comments on the Quality of English Language

minor editing of english language

Author Response

Please find attached the author's review document

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

It is not correct to present TGA plots with values of mass loss higher than 100% because mass loss is a relative measure, and a value greater than 100% implies a mass gain for polymer sample, which is physically impossible. The mass loss percentage is calculated based on the initial mass of the sample, and any value exceeding 100% would suggest that the sample has gained mass during the process, which contradicts the basic principles of TGA.

Author Response

Please find attached document for response to reviewer.

Author Response File: Author Response.docx