Soybean By-Products Bioplastic (Polylactic Acid)-Based Plant Containers: Sustainable Development and Performance Study

Round 1

Reviewer 1 Report

The manuscript reports on development of soybean-based composites and bio-containers. It is an interesting subject on the area of sustainability. However, the novelty of the study is not clear and some detailed comments that need to be addressed are as below:

 

1)Why was SPI used in this study despite higher cost of this substance?

2)Figure 2: The actual name of the polymer should be included instead of ‘plastic’.

3)L153: What conditions were employed in injection molding?

4)What was the models and manufacturers of extruder and injection molding machines?

5)Why was no experimental design employed in this study?

6)Experiments were conducted in how many replicates?

7)Standard deviation or a proper error factor should be included in the tables for the responses/properties measured in the tables.

8)Part of the results should be presented in the form of figures instead of all tables.

9)Discussion should be improved with more references.

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

In the work, research was carried out on the production of biodegradable containers for flowers from biocomposites PLA-soy hulls-soy protein isolate and the biodegradation of these products was assessed. The work is about an interesting research goal. I have the following questions/comments:

1. Why was ANOVA used? Has an analysis been performed for other methods, e.g. Taguchi?

2. Whether the results were statistically processed. How many samples of each type were tested for?

3. Please describe the biocomposite extrusion process in more detail. At what rotational speeds of the screw was extrusion carried out? What was the extrusion yield? Have there been problems with extrusion, e.g. pressure increase at the screw face or extrudate delamination?

4. For what processing parameters were the samples injected? What processing parameters were selected (holding pressure, holding time, injection temperature, mold temperature, injection time/injection speed).

5. The work requires major editorial improvement in accordance with the MDPI guidelines.

6. I recommend extending the literature introduction with items from the last three years (e.g. from POLYMERS or MATERIALS magazines), which deal with issues related to modern polymeric materials with a matrix of another biopolymers. For example, you can raise the topic: the influence of chosen plant fillers in biocomposites on the processing conditions, mechanical properties and quality of molded pieces or influence the alkali treatment of natural fillers on the properties of their biocomposites.

7. Why were these and not other mass ratios of fillers and PLA matrix selected?

8. What was the distribution of the filler in the polymer matrix in the finished pots? Was the filler uniformly distributed or did clusters/aggregates form?

9. Were biodegradation tests carried out according to a standard (e.g. ISO or ASTM)?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The comments are addressed carefully. The manuscript is suggested for publication.