Verification of Utilizing Nanowaste (Glass Waste and Fly Ash) as an Alternative to Nanosilica in Epoxy

Round 1

Reviewer 1 Report

The paper reports the investigation of waste nanopowders used as fillers in composites-based epoxy. The topic is interesting in terms of circular economy and sustainability. Nevertheless, the authors deal with the subject in a very brief way. My detailed comments are as follows:

1. Please add more results to the abstract and make it more precise. For example, the expression:  "A little reduce in magnitudes" is not exact enough.

2. Please emphasize why is this particular research important and what are the novel findings in comparison to existing literature data.

3. Throughout the paper, the authors use some expressions which are too casual, for example, in line 48 "tiny size" which is not a precise scientific expression. The same applies to "enormous specific surface area" in line 51

4. Line 70: P in percent should not be the capital letter

5. Line 94: A dot is missing

6. Where did the ash come from (industrial power plant, domestic furnace, etc.) and what was its origin (coal ash, biomass ash or other)? The type of ash is essential information when it comes to its application.

7. In the Methods and Materials please include more information on how the nanopowders were prepared. The sentence "powders were created using mechanical techniques" is not covering the scope. Please elaborate on the preparation methods.

There is no analysis of nanopowders morphology. The following parameters of nanopowders are vital: particle size distribution, density, specific surface area, purity and morphology (SEM pictures).

8. The Results and Discussion section is very brief. The authors prepared several variations of each specimen (0, 5, 10, 15, and 20 wt% of nanopowders). This is a good base for a more detailed discussion and conclusions.

Author Response

Reviewer 1

Comments and Suggestions for Authors

The paper reports the investigation of waste nanopowders used as fillers in composites-based epoxy. The topic is interesting in terms of circular economy and sustainability. Nevertheless, the authors deal with the subject in a very brief way. My detailed comments are as follows:

1. Please add more results to the abstract and make it more precise. For example, the expression: "A little reduce in magnitudes" is not exact enough.

More results has been added to the abstract and the expression has been modified according to the reviewer’s comment.

2. Please emphasize why is this particular research important and what are the novel findings in comparison to existing literature data.

Addressed in the introduction section according to the reviewer’s comment.

3. Throughout the paper, the authors use some expressions which are too casual, for example, in line 48 "tiny size" which is not a precise scientific expression. The same applies to "enormous specific surface area" in line 51

Addressed according to the reviewer’s comment.

4. Line 70: P in percent should not be the capital letter.

Addressed according to the reviewer’s comment.

5. Line 94: A dot is missing

Addressed according to the reviewer’s comment.

6. Where did the ash come from (industrial power plant, domestic furnace, etc.) and what was its origin (coal ash, biomass ash or other)? The type of ash is essential information when it comes to its application.

Addressed according to the reviewer’s comment.

7. In the Methods and Materials please include more information on how the nanopowders were prepared. The sentence "powders were created using mechanical techniques" is not covering the scope. Please elaborate on the preparation methods.

Addressed according to the reviewer’s comment.

There is no analysis of nanopowders morphology. The following parameters of nanopowders are vital: particle size distribution, density, specific surface area, purity and morphology (SEM pictures).

All the parameters mentioned in table 2, except the SEM images, which is not available due to absence of the device at the research center. However, the use of SEM will be considered in our future research.

8. The Results and Discussion section is very brief. The authors prepared several variations of each specimen (0, 5, 10, 15, and 20 wt% of nanopowders). This is a good base for a more detailed discussion and conclusions.

 Addressed according to the reviewer’s comment.

Reviewer 2 Report

This paper introduces the use of nano-waste (glass waste and fly ash) as a substitute for nano-silica in epoxy resin, which has certain innovation and application value, but still needs improvement. Specific recommendations are as follows:

2. Materials and Methods

Q1: For the reproducibility of the experiments, the technical properties of the epoxy resins sent in the article (especially epoxy value and viscosity) should be explained. (Page 2, Line 95)

Q2: The technical properties of the raw materials, the preparation process, and the test methods should be distributed and described, from the aspect of the article structure. (Page 2, Line 95~123)

3.1. Results of Fourier Transform Infrared Analysis

Q3: Different wave peaks should be marked in Figure 1, in order to illustrate the effect of different nanomaterials on epoxy resin more clearly. Also, Figure 1 is blurry and it is recommended to increase the resolution. (Page 4, Line 151)

3.2. Results of Glass Transition Temps

Q4: The effect of changes in glass transition temperature on the material, as well as the effect (advantages and disadvantages) on practical use, should be stated. (Page 4, Line 155~174)

Q5: Figure 2 is blurry and it is recommended to increase the resolution. (Page 5, Line 175)

3.3. Results of Viscosity

Q6: The conclusion that the addition of nano powders will increase the viscosity of epoxy resins has been extensively verified, and epoxy resins with high viscosity have corresponding advantages. However, how to balance the drop in workability brought about by high viscosity. (Page 5, Line 179~194)

 

Q7: This paper studies the feasibility of replacing nano-silica with waste powder with silica. From a technical point of view, it is feasible, however, it needs to supplement application scenarios, economic benefits, and environmental benefits.

 

 

Author Response

Reviewer 2

Comments and Suggestions for Authors

This paper introduces the use of nano-waste (glass waste and fly ash) as a substitute for nano-silica in epoxy resin, which has certain innovation and application value, but still needs improvement. Specific recommendations are as follows:

2. Materials and Methods

Q1: For the reproducibility of the experiments, the technical properties of the epoxy resins sent in the article (especially epoxy value and viscosity) should be explained. (Page 2, Line 95) it has been added.

 Added according to the reviewer’s comment.

Q2: The technical properties of the raw materials, the preparation process, and the test methods should be distributed and described, from the aspect of the article structure. (Page 2, Line 95~123)  

Addressed according to the reviewer’s comment.

3.1. Results of Fourier Transform Infrared Analysis

Q3: Different wave peaks should be marked in Figure 1, in order to illustrate the effect of different nanomaterials on epoxy resin more clearly. Also, Figure 1 is blurry and it is recommended to increase the resolution. (Page 4, Line 151)  it has been changed

1-The values for the required peaks were determined and mentioned in the discussion, and there is no need to add a mark on the figure.

2-  increase the resolution  (Done as much as possible (the problem occurs when reducing the size of the shape)) it has been added

3.2. Results of Glass Transition Temps

Q4: The effect of changes in glass transition temperature on the material, as well as the effect (advantages and disadvantages) on practical use, should be stated. (Page 4, Line 155~174) 

Addressed according to the reviewer’s comment.

Q5: Figure 2 is blurry and it is recommended to increase the resolution. (Page 5, Line 175) 

Addressed according to the reviewer’s comment.as much as possible (the problem occurs when reducing the size of the shape)

3.3. Results of Viscosity

Q6: The conclusion that the addition of nano powders will increase the viscosity of epoxy resins has been extensively verified, and epoxy resins with high viscosity have corresponding advantages. However, how to balance the drop in workability brought about by high viscosity. (Page 5, Line 179~194)

Balancing occurs by

1- Adding small amount of powder in order not effect on viscosity.  

2-  Accelerating the work after adding the hardener, especially during the molding process

 

Q7: This paper studies the feasibility of replacing nano-silica with waste powder with silica. From a technical point of view, it is feasible, however, it needs to supplement application scenarios, economic benefits, and environmental benefits.

These points added to the introduction part.

Round 2

Reviewer 1 Report

The authors have improved the paper. It is sufficient for publication in Energies.

Reviewer 2 Report

There is no modification suggestion.