Ester Exchange Modification for Surface-Drying Time Control and Property Enhancement of Polyaspartate Ester-Based Polyurea Coatings

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

For the synthesis process, please present with a diagram for better understanding.

For the FTIR analysis, the qualitative formation of ester linkage can be visible. Is there any possibility to carry out quantitative comparison on the ester linkage which can affect the functionalities

May I know whether the surface drying is affected by the concentration or amount of solvent added? Any indication about the solvent will affect the drying time.

 

Usually when the tensile strength is low, the elongation will be higher. However, the observation shows opposite  for 3 (b) and 3(c). Any further explanation on this?

 

Why for IPDA DEM has high shore hardness but lower in tensile strength. Any explanation on this?

 

Do you carry out DTG analysis for TGA for better viewing of the degradation

For the DSC analysis of the Tg, I am doubt with the result in S6 to S10 becuase I cannot observed the transition trends of Tg. Kindly indicate how the Tg is found in the Figure 5. Please show in the Figure 5.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

From my poit of view this is a very interesting and well written paper. There are several advantages:

1.      Fast development of polyurea coatings, especially the third generation of PU, lacking scientific background. This paper fills this gap (lines 53 – 55)

2.      Advantage of PU coatings, easy varying soft-hard segments ratio enabling tailoring mechanical properties is especially interesting in the PAE-PUA systems, still lacking scientific background (lines 68 – 71)

3.      Starting materials, diethyl maleate and various discussed diamines are relatively easy to synthetise, without solvents, opens broad window for possible applications an research (especially permeability studies) (lines 80 – 83; 106 – 107; 119 – 121; 145 - 149)

4.      Clear presentation of reaction procedure (Scheme 1)

5.      Good research, all measurements were triplicated or in the case of Sh-A five fold repeated

6.      Carefull edition, only minor easy to correct editorial mistakes (line 71 should be …PAE-PUA [26-28]…; line 345 should be …Shore A hardness….; line 390 should be …PAE-PUA [37]….; line 399 should be …crosslinking [39]…; line 413 should be …series (Figure 4c)….; line 418 should be …series (Figure 4d)…; line 340 should be …series (Figure 5c)…; line 443 should be …series (Figure 5d)…

7.      Interesting result in TGA with OD added. Usually long hydrocarbon chain is causing lowering of thermal resistance (acting as a plasticizer) and here we observe something opposite. This direction of research is worth to be continued.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I am satisfied with the response and correction by the authors