This document summarizes an experiment to synthesize bioplastic films from banana peels. The objective was to identify processing parameters that yield films with maximum tensile strength. Films were produced by hydrolyzing starch in peels with acid at varying pH, time, and plasticizers. Tests showed neutral pH films with 15 minute hydrolysis and sorbitol plasticizer had the highest tensile strength of 26.06 MPa. Overall, the experiment demonstrated banana peels can be used to create biodegradable plastic films through controlled hydrolysis of peel starch.

1. Bioplastics
Synthesis of polymeric films
using waste banana peels
Abhijit Mohapatra 60011100028
Hemant Sharma 600011100054
Shruti Prasad 60011100034

2. Why Banana Peels?

3. Objective of the Project
 The Objective of this project was to synthesize bio-polymeric films
from banana peels and identify the ideal combination of parameters
which would give the maximum tensile strength to the sample.
 The parameters considered were :
i. pH of the reaction mixture
ii. Residence time for hydrolysis of the reaction mixture
iii. Choice of plasticizer

4. Procedure for Synthesis
 Preparation of Banana Paste
Boiling
Decant
water
Drying Grinding

5.  Production of Film
25gm
Paste
Add 3ml
HCl
Add 2ml
Plasticizer
Add NaOH Baking
Polymeric
film

6. Reaction Mechanism
Starch consists of two different types of
polymer chains:
1. Branched chained
amylopectin
2. Linear Chained
Amylose

7. Hydrolysis
 Amylose is a straight polymer, a desirable polymer
to make plastic
 Amylopectin is branched polymer which makes the
plastic brittle
 Acid Hydrolysis is done to break the branched
chains of amylopectin to aid plastic formation

8. Addition of Plasticizer
 The Plasticizer gets in between the polymer
chains and prevents them from lining up in rows
to form a crystalline structure.
 The Plasticizer increases flexibility, and
develops the plasticity of the product.

9. Addition of NaOH
 If hydrolysis time is prolonged, amylose
also gets hydrolysed
 Hence, NaOH is added to neutralize the
Acid

10. Phase wise Synthesis


11. Trials Conducted
 9 Experimental trials were conducted, out of this 3 were
accepted for testing
 Reasons for discarding samples:
• Perforations on the sample
• Incomplete baking
• Incorrect Concentration of reagents

12. Procedure: Tensile Strength Test
 Step 1: Visual inspection
 Step 2: The approved sample is cut into a
2cm by 4cm rectangular slice
 Step 3: The samples are clamped such that
60% of the sample is our testing region
4cm
Sample
20%60%20%
2 cm

13. 

14. Tensile Strength Test Apparatus

15. Observations
pH Residence Time
(Minutes)
Sample Weight (grams)
Acidic 5 1/04-8 341.41
10 1/04-7 351.89
15 3/04-2 200.94
20 1/04-5 271.53
Basic 5 26/03-4 331.2
10 3/04-4 160.9
15 26/03-2 240.89
20 26/03-1 131.15
Neutral 5 3/04-3 231.59
10 1/04-3 331.50
15 1/04-2 406.19

16. pH Sample Thickness (mm)
1 2 3 4 5 Mean
Acidic 1/04-8 0.94 0.9 0.8 0.8 0.74 0.836
1/04-7 0.66 0.62 0.6 0.64 0.62 0.628
3/04-2 0.72 0.6 0.48 0.48 0.5 0.556
1/04-5 0.5 0.52 0.54 0.56 0.42 0.508
Basic 26/03-4 0.62 0.6 0.68 0.7 0.62 0.644
3/04-4 0.9 0.84 0.7 0.78 0.94 0.832
26/03-2 0.66 0.66 0.7 0.7 0.84 0.712
26/03-1 0.6 0.52 0.54 0.48 0.58 0.544
Neutral 3/04-3 0.6 0.64 0.74 0.68 0.78 0.688
1/04-3 0.62 0.58 0.66 0.68 0.66 0.64
1/04-2 0.6 0.52 0.54 0.66 0.58 0.58
1/04-1 0.6 0.52 0.54 0.62 0.52 0.56

17. Analysis

18. 0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0 5 10 15 20 25
TensileStrength(MPa)
Residence Time (mins)
Tensile Strength Vs Residence Time (Combined
Plot)
Acidic
Neutral
Basic
Stage 1

19. 0
5
10
15
20
25
30
35
40
45
50
0 5 10 15 20 25
%Conversion
Residence Time
Conversion Vs Residence Time (Combined)
Acidic
Basic
Neutral

20. Final Trial
pH Plasticiser Residence
Time
(Minutes)
Sample Weight
(grams)
Neutral Glycerine 15 16/04-2 456.2
Neutral Sorbitol 15 16/04-3 794.95
Neutral PEG 15 16/04-4 558.11
Plasticizer Sample Thickness (mm)
1 2 3 4 5 Mean
Glycerine 16/04-2 0.68 0.6 0.6 0.8 0.72 0.68
Sorbitol 16/04-3 0.48 0.5 0.5 0.5 0.6 0.516
PEG 16/04-4 1.1 0.94 0.82 0.8 0.7 0.872

21. Stage 2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
Glycerine
Sorbitol
PEG 400
Tensile Strength for Different Plasticizers
Tensile Strength for
Different Plasticisers Tensile
Strength (N/mm^2)

22. Properties Sorbitol Glycerine PEG
Brittleness Least Flexible Flexible structure Flexible structure
Tensile strength Highest TS
:26.06MPa
14.31MPa 16.14MPa
0 10 20 30 40 50
Glycerine
Sorbitol
PEG
Conversion For Different Plasticizers
Conversion %

23. Suggested PPS

24. Future Scope
 Exploring other Sources of Starch
 Effect of varying concentrations of Reagents
 Extensive Testing
 Extraction of Starch from peels
 Understanding the effect of Reagents on other
components of the peel

25. Thank You