Experimental Research and Transfer Matrix Method for Analysis of Transmission Loss in Multilayer Constructions with Devulcanized Waste Rubber
Round 1
Reviewer 1 Report
1. In abstract, when you firstly mentioned TMM, please give a full name.
2. Line 96 TMM method is a prediction method? Why TMM was selected? The significance should be elaborated in the introdcution section.
3. Are there any other materials used for multilayer constructions? What's the benefit to use devulcanized rubber?
4. The reviewer is not sure about the devulcanized rubber by grinding method. We commonly name the above material as crumb rubber or ground tire rubber. The grinding method just physiclly disintegrates the whole tire rubber into smaller rubber particles. The vulcanized structure still remains inside the rubber. In this case, most s-s and s-c bonds were not broken in this process.
5. The mass ratio between rubber and polyurethane waste resin was not give in this study.
6. The reviewer is worried about the emission issues if the multilayer constructions are used in indoor environment since the waste materials have odor components.
Author Response
- In abstract, when you firstly mentioned TMM, please give a full name.
Corrected Line 22
- Line 96 TMM method is a prediction method? Why TMM was selected? The significance should be elaborated in the introdcution section.
The TMM method has lots of advantages to analyse multilayer constructions, because every layer of the construction could be described by a different transfer matrix. To analyse every layer only wave number and acoustic impedance must be measured. After the verification of the method, sound transmission loss of different configuration of multilayer construction could be predicted by using the same parameters of the materials. The advantages were mentioned in the introduction (lines 99-106).
- Are there any other materials used for multilayer constructions? What's the benefit to use devulcanized rubber?
In the article, plasterboards and devulcanized waste rubber were used for multilayer construction. There are many articles with different materials used, such as steel or wooden plates with mineral wool, honeycomb metameterials, etc. Our idea is to use devulcanized rubber as a recycled material to ensure circular economy principles when the waste is reused to create other structures. Also, rubber has sound dampening properties, which is important in multilayer constructions.
- The reviewer is not sure about the devulcanized rubber by grinding method. We commonly name the above material as crumb rubber or ground tire rubber. The grinding method just physiclly disintegrates the whole tire rubber into smaller rubber particles. The vulcanized structure still remains inside the rubber. In this case, most s-s and s-c bonds were not broken in this process.
Grinding is more like a preprocess treatment method, which is very important for rubber devulcanization. But according to another scientists, preprocess treatment is described as a one of the devulcanization methods. It was mentioned in 81 line. In the article, grinding was changed as a preprocess treatment method.
- The mass ratio between rubber and polyurethane waste resin was not give in this study.
The amount and proportions of hardener and polyurethane resin in each sample were the same but were not disclosed for confidentiality reasons. (lines 141-142)
- The reviewer is worried about the emission issues if the multilayer constructions are used in indoor environment since the waste materials have odor components.
Such studies have been conducted, but they are beyond the scope of this article. On the other hand, this kind of multilayer constructions with devulcanized waste rubber could be used for the creation of enclosures, which could be used to reduce the sound from noisy devises, such as compressors, generators, where the odor parameters are not important.
Reviewer 2 Report
Increase the number of references
For example, for the acoustic absorption of worn tires see the by Asdrubali, Iannace, Umova, Attenborough.
Verify the repeatability of the built specimens.
How many specimens and how many measurements have you performed.
Check the lower and upper limits of the measurement tube.
In figs. 6 check the values seem too high at high frequency.
In the text, the figures are numbered incorrectly.
A comparison with other results by other authors is needed.
Author Response
- Increase the number of references. For example, for the acoustic absorption of worn tires see the by Asdrubali, Iannace, Umova, Attenborough.
The number of references is 35 in this article and is the right number according to the guide for authors of this journal. Furthermore, acoustic absorption is beyond the scope of this article.
- Verify the repeatability of the built specimens.
The amount of rubber granules, polyurethane resin and hardener was controlled during the mixing of the rubber composites and the proportions were represented in this article.
- How many specimens and how many measurements have you performed.
3 samples of the same rubber composition were made, which was used for the measurements. It was fulfilled on line 149
- Check the lower and upper limits of the measurement tube.
The limits are correct and are according impedance tube specifications.
- In figs. 6 check the values seem too high at high frequency.
In Fig. 6, predicted values of transmission loss were presented. It is normal to have higher results in high frequencies in prediction models because impedance tube have limitations due to the flanking sound.
- In the text, the figures are numbered incorrectly.
Numbers of figures were corrected.
- A comparison with other results by other authors is needed.
A comparison with other authors was made in the discussion section.
Reviewer 3 Report
The manuscript is interesting; However, I have the following comments for improvements.
1). Figures numbers are not correctly mentioned in the Figure and in the text, which makes confusion while reading
2). Lines 62 and 360 have typo errors in the unit; Line 173 also has typo errors.
3). Kindly describe the abbreviations properly
Minor typo errors
Author Response
The manuscript is interesting; However, I have the following comments for improvements.
- Figures numbers are not correctly mentioned in the Figure and in the text, which makes confusion while reading
Numbers of figures were corrected.
- Lines 62 and 360 have typo errors in the unit; Line 173 also has typo errors.
Corrected
- Kindly describe the abbreviations properly
The full name of the abbreviation was written when it was first mentioned.
Reviewer 4 Report
This manuscript discusses experimental research and transfer matrix method for analysis of transmission loss of multilayer constructions with devulcanized waste rubber. The manuscript is written well and claimed research objectives are adequately supported by the results and discussions.
Author Response
This manuscript discusses experimental research and transfer matrix method for analysis of transmission loss of multilayer constructions with devulcanized waste rubber. The manuscript is written well and claimed research objectives are adequately supported by the results and discussions.
Comment:
-
Round 2
Reviewer 3 Report
The authors have addressed all of my comments in the revised version.
