Prediction of the Elastic Properties of Ultra High Molecular Weight Polyethylene Reinforced Polypropylene Composites Using a Numerical Homogenisation Approach

Round 1

Reviewer 1 Report

The article has predicted the elastic properties of UHMWPE/PP composites using a numerical manner, which is interesting. The manuscript can be accepted after well revisions. The reviewer’s comments are as follows:

(1)      What is the biggest contribution of this study? The reviewer cannot see the significance of this study which must be well presented.

(2)      The introduction should be divided into several paragraphs to clearly elaborate the key contents. The conclusions should be rewritten following (1), (2), … (3) to emphasise the key points.

(3)      Why polypropylene (PP) and ultra-high molecular weight polyethylene (UHMWPE) textile composites? Based on the authors’ descriptions, it is actually UHMWPE reinforced PP composites, viz. UHMWPE/PP. Relevant parts must be revised accordingly in the context.

(4)      The title is suggested to be corrected as “Prediction of the Elastic Properties of Ultra-High-Molecular-Weight Polyethylene reinforced Polypropylene composites using a numerical homogenisation approach”.

(5)      The study is very limited by just considering the prediction of elastic properties. The authors must consider or discuss more on some other more important performance predictions, such as thermal properties: Compos Sci Technol 2022; 227: 109599, failure performance: Compos Struct 2017; 168: 322-334, Thin-Walled Struct 2023; 184: 110552, etc.

(6)      English expression must be carefully polished. e.g. “The Monte Carlo (MC) approach was applied to the code for generating the PP/UHMWPE composite analysis models to implement a composite model in which UHMWPE textiles are evenly distributed in the PP matrix”, etc.

Author Response

The article has predicted the elastic properties of UHMWPE/PP composites using a numerical manner, which is interesting. The manuscript can be accepted after well revisions. The reviewer’s comments are as follows:

(1)      What is the biggest contribution of this study? The reviewer cannot see the significance of this study which must be well presented.

-I added the following sentence to the introduction to address the need for the study.
"To compensate for the shortcomings of existing fiber-based composites, the develop-ment of woven isotropic composites will expand the range of applications of polymer composites. For further research on UHMWPE/PP woven composites, it is necessary to analyze their elastic properties using finite element analysis methods. "

(2)      The introduction should be divided into several paragraphs to clearly elaborate the key contents. The conclusions should be rewritten following (1), (2), … (3) to emphasise the key points.

- Separated the paragraphs in the introduction and rewrote the conclusion sequentially.

(3)      Why polypropylene (PP) and ultra-high molecular weight polyethylene (UHMWPE) textile composites? Based on the authors’ descriptions, it is actually UHMWPE reinforced PP composites, viz. UHMWPE/PP. Relevant parts must be revised accordingly in the context.

- As described in the Introduction, we want to combine the versatility and processability advantages of PP with the mechanical properties of UHMWPE.
- Corrected all notations to "UHMWPE/PP".

(4)      The title is suggested to be corrected as “Prediction of the Elastic Properties of Ultra-High-Molecular-Weight Polyethylene reinforced Polypropylene composites using a numerical homogenisation approach”.

- Corrected the title.

(5)      The study is very limited by just considering the prediction of elastic properties. The authors must consider or discuss more on some other more important performance predictions, such as thermal properties: Compos Sci Technol 2022; 227: 109599, failure performance: Compos Struct 2017; 168: 322-334, Thin-Walled Struct 2023; 184: 110552, etc.

- We have conducted basic research on the morphology of woven fabrics. Currently, we are conducting research by comparing the mechanical, thermal, and fatigue failure properties of woven fabrics with experimental values depending on the angle and orientation of the woven fabric.
- We prioritized the recommended papers and added them as references.

(6)      English expression must be carefully polished. e.g. “The Monte Carlo (MC) approach was applied to the code for generating the PP/UHMWPE composite analysis models to implement a composite model in which UHMWPE textiles are evenly distributed in the PP matrix”, etc.

- We reviewed the English expressions once again.

Reviewer 2 Report

This is a timely effort by authors on "Study on the Prediction of the Elastic Properties of Polypropylene/Ultra-High-Molecular-Weight Polyethylene Textiles using 3D Modeling". However, I am really concerned about the technical vitality of this work.

1.  I am really concerned about the novelty of this work as compared to previous body of literature.

2. Introduction may be enhanced using many merged references by discussing each of them one by one.

3. Materials and methods have few basic errors relevant to simulation settings. Please see my comments below in this regard.

4. At page and line 153, the element type should be SOLID187 instead of mesh type.

5. How did you select the mesh size 0.5 micrometer for your simulations?

6. H value is not clear. Please define it first and its importance.

7. The difference in the values for different composite setting seems huge in figures for similar kind of moduli. What do you think why this happened?

8. Discussion section must be enhanced with a validation of results even with those of similar studies. This must be done to check the real accuracy of current simulation in the absence of empirical validation.

9. The conclusion section must be reduced as much as possible..

10. Moreover, few figures from the Ansys software showing various mechanical properties of composites, must be included in the main manuscript.

Author Response

1.  I am really concerned about the novelty of this work as compared to previous body of literature.

- The novelty of our research is the following: we want to develop polymer composites in the form of woven fabrics. In advance, it should be possible to predict the expected properties of the material. 

We have added the above to the introduction.

2. Introduction may be enhanced using many merged references by discussing each of them one by one.

- Research utilizing UHMWPE is limited. Most of the current research on composites is on fiber-based reinforcement mechanisms; therefore, there is a lack of research reporting on woven composites, making it ambiguous to link references individually.
- With continued research by our team, the goal is to develop polymer-polymer composites in woven form.

3. Materials and methods have few basic errors relevant to simulation settings. Please see my comments below in this regard.

- Our team wants to incrementally improve our finite element analysis, based on experimentation. We will continue to evolve the analytical model with the reviewer's input.

4. At page and line 153, the element type should be SOLID187 instead of mesh type.

-Correction.

5. How did you select the mesh size 0.5 micrometer for your simulations?

- Set to take into account the size of the 3D model used in the finite element analysis. This is to ensure the convergence of the finite element analysis considering the sensitivity of the model. It is also derived from the empirical model. 

6. H value is not clear. Please define it first and its importance.

- I noticed that the description of the H value is missing.
We have added the following explanation

H corresponds to the horizontal area length ratio in the fiber cross section. This value is what controls the volume of the fabric while maintaining its shape. In the 3D model used in this study, the final volume fraction of the fabric is controlled by the horizontal area length ratio of the woven fibers.

7. The difference in the values for different composite setting seems huge in figures for similar kind of moduli. What do you think why this happened?

- We've added the following explanation to the conclusion
- The elastic properties of composites depend on the properties and volume fractions of the materials used. As the volume of the UHMWPE weave increases, the material's properties improve, due to the superior properties of UHMWPE. On the other hand, if the volume fraction of UHMWPE is reduced, the material properties can be closer to PP.

8. Discussion section must be enhanced with a validation of results even with those of similar studies. This must be done to check the real accuracy of current simulation in the absence of empirical validation.

- According to the current research progress and the results of similar studies, experimental methods should be performed to validate the finite element analysis of our research. Therefore, for development purposes, we are currently fabricating woven fabrics from UHMWPE yarns and are in the process of manufacturing woven composites through a hot-belt process or a hot-press process. We will publish additional papers based on images and experimental results that can verify our finite element analysis results later this year.

9. The conclusion section must be reduced as much as possible..

- For the conclusion, I simplified it by changing it to a numbering.

10. Moreover, few figures from the Ansys software showing various mechanical properties of composites, must be included in the main manuscript.

- This is a very, very difficult opinion.
In general, Ansys modules that predict elastic properties do not produce a plot of the results. They produce graphs and tables of the results when the materials are mixed as modeled. This makes it difficult to attach the results of a finite element analysis.

Reviewer 3 Report

1.      Several references and citations that should be included are missing from the introduction section. Also, extraneous references should be deleted.

2.      Divided the introduction into a few paragraphs, and the introduction should include the significance of the study, a literature review to aid the study, and a highlight of the current work in comparison to other studies.

3.      The information in Table 1 should be integrated with the original sources/references. Edit the mistake in kg/m3 in the table.

4.      For, Figures 3-5 the fitting equations to the fitted points should be inserted.

5.      The application of the investigated materials should be highlighted to be published in Applied Sciences.

6.      To demonstrate the validity of the suggested model, some experimental data from the literature should be used.

Author Response

1.      Several references and citations that should be included are missing from the introduction section. Also, extraneous references should be deleted.

- Added more relevant references, in the introduction.
-I don't think there are any unnecessary references.
-If there are other essential references, please recommend them.

2.      Divided the introduction into a few paragraphs, and the introduction should include the significance of the study, a literature review to aid the study, and a highlight of the current work in comparison to other studies.

- The introduction is divided into paragraphs based on content.
We also added a section on the novelty of the study.

3.      The information in Table 1 should be integrated with the original sources/references. Edit the mistake in kg/m3 in the table.

- Added references to material properties.
-Since the physical properties of UHMWPE were provided by Mipleon, it is not suitable for reference in the paper, so we have attached the previous research data.
-Corrected the presentation of units.

4.      For, Figures 3-5 the fitting equations to the fitted points should be inserted.

- Corrected by inserting the fitting equation in the graph.

5.      The application of the investigated materials should be highlighted to be published in Applied Sciences.

-The need for material development was mentioned in the introduction.
The development of biaxially isotropic composites is a necessary part of the industry.

6.      To demonstrate the validity of the suggested model, some experimental data from the literature should be used.

- According to the current research progress and the results of similar studies, experimental methods should be performed to validate the finite element analysis of our research. Therefore, for development purposes, we are currently fabricating woven fabrics from UHMWPE yarns and are in the process of manufacturing woven composites through a hot-belt process or a hot-press process. We will publish additional papers based on images and experimental results that can verify our finite element analysis results later this year.

Round 2

Reviewer 1 Report

The reviewer's comments are basically addressed.

Author Response

Thank you for your review comments.

Reviewer 2 Report

The authors have improved the manuscript. However, they should focus on following suggestions before accepting this manuscript.

1. Discussion section must be enhanced with a validation of results even with those of similar studies available in the literature. This must be done to check the real accuracy of current simulation in the absence of empirical validation.

2. Few figures from the Ansys software showing various mechanical properties (with changing colors for various properties) of composites, must be included in the main manuscript.

Author Response

1. Discussion section must be enhanced with a validation of results even with those of similar studies available in the literature. This must be done to check the real accuracy of current simulation in the absence of empirical validation.

- Currently, there are no experimental or finite element analysis papers on the prediction of elastic properties for composites of UHMWPE woven and PP. 
Therefore, to validate our analysis, we cited references from other materials in the form of woven fabrics.
We emphasize the validity of our results based on data of similar shape.

2. Few figures from the Ansys software showing various mechanical properties (with changing colors for various properties) of composites, must be included in the main manuscript.

- As in the previous answer, the finite element analysis in this study does not show any results for strength, so there are no results for finite element analysis.
Instead, a predicted value is produced. 
It is a finite element analysis in which the output variable (property value) of the composite material is derived according to the input variable (property). 
We release part of the basic data sheet as an attachment for your reference.

Author Response File: Author Response.pdf