Comparative Environmental Life Cycle Assessment on Corn Starch Plasticization and Co-Plasticization Processes
and Manjusri Misra 1,2,*Round 1
Reviewer 1 Report
Comments and Suggestions for Authorsa) Some paragraphs are too long and could be shortened;
b) Please, make clear the unit "phr";
c) The results presented in Table 5 could be more discussed;
d) Revise the size of some tables (the size of text and width of columns);
e) Please, justify in more detail the choice of scenarios 1 and 2;
f) "Category" instead of "Catogory";
g) More insights and comparisons with scientific literature are expected.
Comments on the Quality of English LanguageThere are only minor revisions in terms of puctuaction and some wrong words (misprints).
Author Response
Q1: Some paragraphs are too long and could be shortened
Answer: Thank you for your comments and suggestions. The paragraphs were shortened throughout the text and were corrected.
Q2: Please make clear the unit “phr”
Answer: Thank you for your comments and suggestions. The Full form of the abbreviation is added at the bottom of the table 1. (line number 151 in the revised manuscript)
Q3: Revise the size of some tables (the size of the text and the width of columns)
Answer: Thank you for your comments and suggestions. Tables 6 and 7 have been revised for more clarity. (line number 260 and 288 in the revised manuscript)
Q4: Please justify in more detail the choice of scenarios 1 and 2;
Answer: Thank you for your comments and suggestions. The first paragraph of the sensitivity analysis (section 4) has been updated for more clarity (lines 237-247 in the revised manuscript).
Q5: “Category” instead of “Catogory”
Answer: Thank you for your comments and suggestions. The term Category is corrected in Figures 2,3 and 4.
Q6: More insights and comparisons with scientific literature are expected.
Answer: Thank you for your comments and suggestions. Limited studies exist on the life cycle assessment of the effect of plasticizers on TPS development. However, we have incorporated more articles and comparisons to support our findings (line 172-199 in the revised manuscript).
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe study compared the environmental impacts of different starch plasticization methods, including co-plasticization (glycerol-urea, glycerol-citric acid, glycerol-succinic anhydride) and conventional glycerol plasticization, using life cycle analysis (LCA). The results showed that co-plasticization with glycerol-citric acid and glycerol-succinic anhydride had similar environmental impacts to the traditional glycerol method. However, glycerol-urea plasticization had the largest negative impact. In order to reduce the impact, a sensitivity analysis was conducted, modifying the energy consumption in the processes using quantitative and qualitative methods. The qualitative approach significantly reduced the impacts on key categories such as global warming, cancer risk, ecotoxicity and fossil fuel depletion.
The publication contains important information related to the current trend of searching for new materials of natural origin that can replace petrochemical plastics. Thermoplastic starch is an example of this. The content of the work corresponds to the topic specified in the title. The sources were selected appropriately. The chapter "Literature" consists of 22 items - in most cases these are scientific publications and books. I have no objections to the content. However, the publication contains minor editing errors that are worth correcting, e.g. in Figure 2, 3, 4 the heading "Impact Catogory" should be corrected to "Impact Category". The tables can be presented more clearly, e.g. Table 6, 7.
Author Response
The study compared the environmental impacts of different starch plasticization methods, including co-plasticization (glycerol-urea, glycerol-citric acid, glycerol-succinic anhydride) and conventional glycerol plasticization, using life cycle analysis (LCA). The results showed that co-plasticization with glycerol-citric acid and glycerol succinic anhydride had similar environmental impacts to the traditional glycerol method. However, glycerol-urea plasticization had the most significant negative impact. To reduce the impact, a sensitivity analysis was conducted, modifying the energy consumption in the processes using quantitative and qualitative methods. The qualitative approach significantly reduced the impacts on key categories such as global warming, cancer risk, ecotoxicity and fossil fuel depletion.
The publication contains important information related to the current trend of searching for new materials of natural origin that can replace petrochemical plastics. Thermoplastic starch is an example of this. The content of the work corresponds to the topic specified in the title. The sources were selected appropriately. The chapter "Literature" comprises 22 items - in most cases, scientific publications and books. I have no objections to the content. However, the publication contains minor editing errors that are worth correcting
Q1: In Figures 2, 3, and 4, the heading Impact Category'' should be corrected to "Impact Category.
Answer: Thank you for your comments and suggestions. The term Category is corrected in Figures 2,3 and 4.
Q2: The tables can be presented more clearly, e.g. Tables 6 and 7.
Answer: Thank you for your comments and suggestions. Tables 6 and 7 have been revised for more clarity. (line number 260 and 288 in the revised manuscript)
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsComments for author File: Comments.pdf
Author Response
Recommendation
This paper provides an LCA method to compare different improved co-plasticizers with traditional and commercial ones. The main topic of the research is interesting and well-organized. There are only some weak points that the authors should present clearly, and it is suggested that they better illustrate the scientific contribution of the study. The following comments can be considered for further improvement.
Introduction
Q1: Lines 41-44: Short sentences improve readability.
Answer: Thank you for your comments and suggestions. All sentences (Lines 41-44 in the revised manuscript) have been improved for optimal readability.
Q2: Line 62: The full name of TPS (Thermoplastic Starch) should be introduced in the first instance.
Answer: Thank you for your comments and suggestions. The term thermoplastic starch is added in line 60, where it is used for the first time.
Q3: Clearly point out the gaps from previous studies: Previous studies have not adequately addressed the environmental impacts of using alternative co-plasticizers in TPS. Additionally, there is limited data on the end-of-life impacts of these materials.
Answer: Thank you for your comments and suggestions. The sentences were added at the end of the introduction. (line number 94-97 in the revised manuscript)
Method
Q4: In Figure 1, the keywords "waste from processing" and "end of life" should be placed outside the dotted frame, indicating they are out of the system boundary.
Answer: Thank you for your comments and suggestions. The study included waste after processing (15%) and its end-of-life. Thus, they are inside the system boundary.
Q5: Ensure consistency of tenses throughout the methods section. For example, use the past tense uniformly: "The study was conducted using..."
Answer: Thank you for your comments and suggestions. The sentences in section 2 have been corrected to pass tense.
Q6: Line 129: Cite the sources of Ecoinvent 3 and Simapro. For example, "Data was obtained from Ecoinvent 3 (citation) and Simapro (citation)."
Answer: Thank you for your comments and suggestions. The citations for the software and database have been added in the third line of the materials and methods section.
Q7: Present data sources for Tables 1, 2, and 3. For example, "Data for Tables 1, 2, and 3 were sourced from [insert source]."
Answer: Thank you for your comments and suggestions. The source has been added: "Tables 1, 2, and 3 were sourced from the SimaPro software that used the Ecoinvent database [1,2].”
Results
Q8: Lines 173-175: Quantify the results found in literature 12. For example, "Literature 12 reports a reduction in greenhouse gas emissions by 20% when using alternative co-plasticizers."
Answer: Thank you for your comments and suggestions. The sentence has been rewritten for clarity (line number 176-178 in the revised manuscript)
Q9: Present the differences compared with other studies.
Answer: Thank you for your comments and suggestions. In the result and discussion section, more related studies were incorporated.
Sensitivity Analysis
Q10: Fluctuation ranges are categorized by degree from maximum to minimum. Use gradient colours in Tables 6 and 7 to indicate these ranges.
Answer: Thank you for your comments and suggestions. Tables 6 and 7 were categorized by degree from maximum to minimum using gradient colours. (line number 260 and 288 in the revised manuscript)
Conclusion
Q11: Avoid using abbreviations for ”reduced energy consumption“ in this section.
Answer: Thank you for your comments and suggestions. The abbreviation has been removed.
References
[1] PRé Sustainability, “SimaPro 8.4.0,” PRé , 2017, accessed on August 5, 2024, https://support.simapro.com/s/.
[2] Ecoinvent Association, “ecoinvent v3.10,” ecoinvent Association, 2023, https://ecoinvent.org/ecoinvent-v3-10/.
Author Response File: Author Response.pdf
