physicochemical characterization of biodegradable plastic

Journal of Environmental Engineering & Sustainable Technology JEEST Vol. 06 No. 02, November 2019, Pages 57-65 http://jeest.ub.ac.id

P-ISSN:2356-3109 E-ISSN 2356-3117 57

PHYSICOCHEMICAL CHARACTERIZATION OF BIODEGRADABLE PLASTIC

FROM UWI TUBER STARCH (DIOSCOREA ALATA) WITH SORBITOL AND

CMC (CARBOXYMETHYL CELLULOSE) AS PLASTICIZER ADDITION

Dina Wahyu Indriani1, Sumardi Hadi Sumarlan, Siti Munawaroh

1 Department of Agricultural Engineering, Faculty of Agricultural Technology, Universitas Brawijaya

Email : [email protected]

ABSTRACT

Uwi tubers (Dioscorea alata) are widely used as

biodegradable plastics materials because it

contains high starch content about 75,6 –

84,3%. Biodegradable plastics can be used as a

decent food wrapping. The purpose of this

research is to study the process of making

biodegradable plastics and analyze the effect of

a adding CMC (carboxymethyl cellulose) and

sorbitol plasticizers on the physicochemical

properties of biodegradable plastics from uwi

tuber starch with various parameters, solubility,

thickness, tensile strength, elongation, modulus

Young, compressive strength, biodegradability

and surface morphology of functional groups.

The making of plastic biodegradables is based

on the melt intercalation method. Uwi tuber

starch composition used was 5 grams, the

combination of CMC concentration used was 0

gram; 0,20 gram; 0,30 gram; 0,40 gram. While

the variations in the volume of sorbitol used are

2 ml, 3 ml, 4 ml, 5 ml. The results of this study

indicate that the additon of 0 gram CMC and 2

ml of sorbitol produce tensile strength values of

7,66 MPa, the best modulus Young is 5,52 MPa.

The compressive strength values is lower that is

equal to 0,150 kgf, the best elongation value is

at the addition of CMC 0,20 gram and sorbitol

5 ml that is equal to 39,44%. The concentration

of the CMC addition and sorbitol plasticizer on

biodegradable plastic affects physical

properties in SEM testing with the additon of 0

gram CMC and sorbitol 2 ml, which results are

denser when compared with the addition of 0,40

gram CMC and 5ml sorbitol. In the FTIR test,

there are C-O alcohol/ester/carboxylic acid/eter

functional groups in waves 1050-1300. Plastics

with the highest concentrations of CMC and

sorbitol need 7 days to be degraded.

Keywords: Biodegradable plastics, CMC, Uwi

Tuber, Sorbitol

1. INTRODUCTION

Almost every product that used plastic as

their packaging has advantages such as light

weight, strong, transparent, waterproof and

relatively cheap and affordable by all people.

Plastics that are widely used today are synthetic

polymers made from chemicals that cannot be

decomposed by microorganisms (non-

biodegradable), and use non-renewable

resources, for example from petroleum raw

materials whose existence is running low. .

Based on this, an alternative is needed to solve

this problem by developing biodegradable

plastic materials. Biodegradable plastics are

plastics that can be used for packaging

foodstuffs like conventional plastics that we

have been using, but biodegradable plastics will

break down by microorganism activity to the

end result in the form of water and carbon

dioxide gas after being discharged into the

environment.

Biodegradable plastic can be made from

organic materials that contain cellulose,

callogen, casein starch, protein, or lipids. One

of the plants that can be used as a basic material

in making biodegradable plastics is starch from

Uwi tubers (Dioscorea alata). Uwi tubers

(Dioscorea alata) has not been used maximally

by the community, therefore it would be very

beneficial if it can change the tubers of Uwi into

a product that has a value, one of them as a raw

material for making biodegradable plastics

because it has quite a lot of starch content,

which is around 75.6 - 84.3% (Hapsari, 2014).

Biodegradable plastic made from starch has low

mechanical strength so additional substances

are needed to correct this. Plasticizer is an

additional material added to natural polymers as

plasticizers, because a mixture of pure natural

polymers will produce brittle and brittle

properties that will increase flexibility and

prevent polymers from cracking (Hikmah,

2015).

mailto:[email protected]

Journal of Environmental Engineering & Sustainable Technology (JEEST) P-ISSN:2356-3109 Vol. 06 No. 02, November 2019, Pages 57-65

58

The purpose of this research is to study

the process of making biodegradable plastics

from Uwi (Dioscorea alata) by adding CMC and

sorbitol plasticizers and to determine the effect

of adding CMC and sorbitol plasticizers to the

physicochemical properties of plastic from Uwi

tubers (Dioscorea alata) including solubility,

thickness, tensile strength, elongation, modulus

young, compressive strength, biodegradability,

and surface morphology of functional groups.

2. RESEARCH AND METHODS

2.1. Tools and materials

The tools used were a hot plate stirrer,

oven, blender, sieve 100 mesh, analytical

scales, measuring cups, stirrers, stopwatch,

glass plates, buckets, trays, bowls, knives,

basins, ruler. Materials used were Uwi tubers

(Dioscorea alata), CMC (Carboymethyl

Cellulose), sorbitol, distilled, Acetone.

Figure 1. Making Biodegradable Plastic from Uwi

Tuber

2.2. Procedure Data Analysis

2.2.1. Water content

Calculation of water content begins by

weighing the mass of the sample with a sample

size of 2 x 2 cm. Then dry it in the oven at 105⁰C

for 4 hours. Then cool in a desiccator for 15

minutes then weight. Then it is reheated in the

oven for 30 minutes. Then cooled in a

desiccator then weighed.

2.2.2. Solubility

The solubility calculation begins by

weighing the initial mass of biodegradable

plastic first. Then immerse the biodegradable

plastic into aquades for 24 hours while

periodically stirring. After 24 hours,

biodegradable plastic is taken and dried at room

temperature. Then the mass of biodegradable

plastic is weighed again after soaking.

Solubility calculations using the formula

(Andriyani, 2018) :

Solubility (%) =B1 − B2

B1 x 100% ............. (1)

Where : B1: Mass sample before immersion (g) B2: sample mass after immersion (g)

2.2.3. Thickness

Thickness measurements are measured

using a coating thickness gauge. biodegradable

plastic measurements are carried out at three

different points, that is the sides and middle of

biodegradable plastic. Thickness values are

obtained from the average measurement results.

This test was carried out three times (triplo).

The value of biodegradable plastic thickness is

obtained using the following formula: Average thickness =

(point 1 + point 2 + point 3 )

3

2.2.4. Strength test

Biodegradable plastic tensile strength test

is performed using a tension testing tool.

Samples were cut with a size of 3 x 7 cm with a

thickness of ≤ 7 mm, then clamped 1.5 cm in

both sides. Extension indicator (extensomer)

installed. Transverse strain gauges installed.

Load and voltage measurements were taken.

The speed of testing is set according to the rate

required. The stress-load curve is recorded.

Also noted are the voltage and load values as

Start

Preparation of material, and equipment

Oven drying at 60ᵒC for 4 hours

Stirr using magnetic stirred for 25 minutes

Add CMC and sorbitol during mixing

Gelatinize at 80ᵒC for 25 minutes

Let stand 15 minutes to get air bubbles out

Platting on a glass plate with a size 20 x 20 cm

5 gram uwi flour + 5 ml distilled water and add 15

ml acetone

Plastic Biodegradable

Finish

Indriani, Sumarlan, Munawaroh, Physicochemical Characterization of Biodegradable Plastic …

P-ISSN:2356-3109 E-ISSN 2356-3117 59

well as the voltage and load values at the time

of breaking up (Jabbar, 2017)

2.2.5. Elongation





both sides. Extension indicator (extensomer)

installed. Transverse strain gauges installed.

Load and voltage measurements were taken.

The speed of testing is set according to the rate

required. The stress-load curve is recorded.

Also noted are the voltage and load values as

well as the voltage and load values at the time

of breaking up (Jabbar, 2017).

2.2.6. Young's Modulus





both sides. Load and voltage measurements

were taken. The speed of testing is set according

to the rate required. The stress-load curve is

recorded. Also noted are the voltage and load

values as well as the voltage and load values at

the time of breaking up (Jabbar, 2017).

2.2.7. Biodegradability

Calculation of biodegradability begins

with weighing the initial mass of biodegradable

plastic first. Then immerse biodegradable

plastic into distilled water for 24 hours while

stirring periodically. After 24 hours,

biodegradable plastic is taken and dried at room

temperature. Then the mass of biodegradable

plastic is weighed again after soaking

(Andriyani, 2018)

3. RESULTS AND DISCUSSION

3.1. Biodegradable Plastics from Uwi Tuber

Overall, the plastic that is produced from

a variety of treatments is clear in color, the

surface is a bit rough, transparent, sticky and

easy to stick when in contact with other objects.

Figure 1, Biodegradable Plastics

This moist and sticky nature is caused by

the nature of CMC which is easy to absorb the

surrounding steam.

3.2. Water Content

Moisture test is performed to determine the

water content of biodegradable plastic. The

results of water content analysis showed that

the treatment of adding 0.4 grams of CMC and

4 ml of sorbitol had the largest water content of

16.97% and the treatment of adding 0 grams of

CMC and 2 ml of sorbitol had the lowest water

content of 12.50%. Average water content of

14.54%.

Figure 2, Graph of Biodegradable Plastic Water

Content (%) Due to the addition of CMC (g) and sorbitol (ml)

The process of making biodegradable

plastic when drying uses a temperature of 60 °

C for 4 hours that will evaporate free water that

is not bound by sorbitol and CMC, but not all

free water can be evaporated. Adding a low

concentration of sorbitol and CMC results in a

low amount of bound water. Meanwhile, the

addition of high concentrations of sorbitol and

CMC can increase the ability to bind water and

increase the total amount of water so that the

water content in the biodegradable plastic

formed has a high water content value.

According to Rahayu (2016), the more CMC

and sorbitol added the higher the water content

value.

3.3. Solubility

The solubility obtained from the

measurement results of biodegradable plastic

samples ranged from 23.87% to 66.01%. The

average solubility value is 51.71%. Based on

ANOVA analysis showed the influence of the

addition of CMC and sorbitol gave significant

results at α <0.05 on the resulting solubility. The

interaction of the combination of the two factors

0

5

10

15

20

0 0.2 0.3 0.4W

ater

Co

nte

nt

(%)

CMC Concentration (gram)

Sorbitol 2 ml

Sorbitol 3 ml

Sorbitol 4 ml

Sorbitol 5 ml


60

also had a significant effect on α> 0.05 so that a

further DMRT (Duncan Multiple Range Test)

test was performed. Based on the DMRT test

that has been obtained, the results for the CMC

factor show that the 0.30 and 0.40 gram

treatments have a more significant effect on the

elongation value of biodegradable plastics

compared to the 0 and 0.20 gram treatments that

are in the second subset. However, the inter

treatment did not have a significantly different

effect. As for the addition factor of sobitol

treatment 2, 3 and 5 mL gives a more significant

effect compared to 5 mL treatment. However,

between treatments did not have a significantly

different effect,

Figure 3. Graph of Biodegradable Plastic Solubility

(%) Due to the addition of CMC (g) and sorbitol

(ml)

Based on the graph above shows that the

greatest biodegradable plastic solubility is at

0.40 gram CMC treatment and 5 ml sorbitol,

with an average of 51.71%, while the smallest

biodegradable plastic solubility is at 0 gram

CMC treatment and 2 ml sorbitol treatment is

26, 72% and the smallest biodegradable plastic

solubility was at CMC 0.40 gram and sorbitol 5

ml at 63.31%. This shows that the solubility

value increases with the addition of CMC and

sorbitol concentrations. In this study, the graph

is not fluctuating. This is due to the non-uniform

thickness of the plastic. The thickness of the

plastic affects its solubility, meaning that the

thicker the plastic, the lower the solubility due

to the compactness of the film as a result of

increasing hydrogen bonds as the thickness of

the plastic increases. Increased hydrogen bonds

cause the molecular structure of starch to bond

together to form a compact network, thereby

reducing the solubility of plastic. CMC is a type

of stabilizer of carbohydrates that can form

colloids in water. The colloidal nature of this

substance as a stabilizer or can stabilize the

suspension. The more addition of CMC causes

more water to be absorbed, which is caused by

CMC being hygroscopic (Nasution et al, 2015).

Addition of sorbitol to the film increases water

solubility. Type and concentration give effect to

the solubility of starch-based films. The more

plasticizer additions will increase the solubility

(Nurhayati et al. 2012). Based on these results

prove that the addition of CMC and sorbitol

more and more will increase water solubility.

3.4. Thickness

The tensile strength obtained from the

measurement results of biodegradable plastic

samples ranged from 14.25 MPa to 76.65 MPa.

Based on the analysis showed the influence of

the addition of CMC and the addition of sorbitol

gave significant results at α <0.05 to the

resulting tensile strength value. The interaction

of the combination of the two factors did not

have a significant effect on α> 0.05, so a further

DMRT (Duncan Multiple Range Test) test was

performed. Based on the DMRT test results

obtained for the CMC factor that the treatment

of 0, 0.20 and 0.40 grams have a more

significant influence on the tensile strength

value of biodegradable plastics in subsets 2 and

3 compared to 0.30 gram treatments that are in

subset 1.

Figure 4. Graph of Thickness Due to Addition of

CMC and Sorbitol

Based on the graph above shows that the

largest biodegradable plastic thickness is at 0.30

gram CMC treatment and 4 ml sorbitol, with an

average of 97.12 µm, while the smallest

biodegradable plastic thickness is at 0.30 gram

CMC treatment and 3 ml sorbitol treatment at

41.07 µm. That the addition of CMC and

sorbitol tends to produce different thickness

thicknesses. The average thickness of

biodegradable plastic is 71.36 µm. This is due

to the influence of printing which is possible for

0

20

40

60

80

0.00 0.20 0.30 0.40

Solu

bili

ty (

%)

CMC Conc. (gram)

Sorbitol 2 ml

Sorbitol 3 ml

Sorbitol 4 ml

Sorbitol 5 ml

0

50

100

150

0.00

0.20

0.30

0.40

Thic

knes

s (µ

m)


sorbitol 2 ml

sorbitol 3ml

sorbitol 4ml

sorbitol 5ml


P-ISSN:2356-3109 E-ISSN 2356-3117 61

differences on each side of the glass plate

because the printing process is done manually.

The difference in magnitude of the resulting

thickness is due to the process of making the

solution.

3.5. Tensile Strength

The tensile strength obtained from the measurement results of biodegradable plastic samples ranged from 14.25 MPa to 76.65 MPa. Based on the analysis showed the influence of the addition of CMC and the addition of sorbitol gave significant results at α <0.05 to the resulting tensile strength value. The interaction of the combination of the two factors did not have a significant effect on α> 0.05, so a further DMRT (Duncan Multiple Range Test) test was performed. Based on the DMRT test results obtained for the CMC factor that the treatment of 0, 0.20 and 0.40 grams have a more significant influence on the tensile strength value of biodegradable plastics in subsets 2 and 3 compared to 0.30 gram treatments that are in subset 1. However, between treatments did not have a significantly different effect. Whereas the addition factor of sobitol treatment 2 and 3 mL gives a more significant effect compared to treatments 4 and 5 mL. However, between treatments did not have a significantly different effect.

Figure 5. Graph of Strength Test Biodegradable

Plastics (MPa) Due to the addition of CMC (g) and

sorbitol (ml)

Based on the graph shows that the

greatest tensile strength of biodegradable

plastic is at CMC treatment of 0 gram and

sorbitol 2 ml, with an average of 76.66 MPa,

while the smallest tensile strength of

biodegradable plastic is at CMC treatment of

0.40 gram and sorbitol of 5 ml that is by an

average of 14.25 MPa. This shows that the

tensile strength value decreases with the

addition of CMC and sorbitol concentrations.

On the addition of CMC decreased showed that

the molecular structure is amorphous.

According to Hasanah et.al (2016), in the

structure of amorphous molecules, chains are

branched but not tightly arranged so that the

distance between molecules becomes farther

and the strength of molecular bonds becomes

weak. The weak strength of the molecular

bonds causes the lower force required to break

the biodegradable plastic. According to

Purwanti (2010), with the addition of sorbitol as

a plasticizer, the plasticizer molecules in the

solution are located between the biopolymer

bonding chains and can interact by forming

hydrogen bonds in the polymeric bonding

chains causing a reduction in less attraction with

the addition of sorbitol.

3.6. Elongation

Extensions obtained from the measurement results of each biodegradable plastic sample ranged from 10% - 38.33%, while the percentage of overall lengthening of biodegradable plastics was an average of 23.85%. Based on ANOVA analysis showed the influence of the addition of CMC and sorbitol gave significant results at α <0.05 on the resulting elongation. The interaction of the combination of the two factors also had a significant effect on α <0.05 so that further tests were carried out by DMRT (Duncan Multiple Range Test). Based on the DMRT test results obtained for the CMC factor that the treatment of 0.20, 0.30 and 0.40 grams give a more significant effect on the elongation value of biodegradable plastics while the treatment of 0 grams does not give a more significant effect on the elongation value is in the second subset. However, the inter treatment did not have a significantly different effect. As for the Sobitol factor treatment 2 and 3 mL gave a more significant effect compared to treatment 5 and 4 mL. However, between treatments did not have a significantly different effect.

Figure 6. Graph of Elongation (%) As a result of

addition of Biodegradable Plastic result CMC (g)

and sorbitol (ml)

0

20

40

60

80

100

0.000.200.300.40

Ten

sile

Str

engh

(M

Pa)


Sorbitol 2 ml

Sorbitol 3 ml

Sorbitol 4 ml

Sorbitol 5 ml

0

20

40

60

0 0.2 0.3 0.4

Elo

nga

tio

n (

%)


sorbitol 2ml

sorbitol 3ml

sorbitol 4ml

sorbitol 5ml


62

Based on the graph shows that the largest

biodegradable plastic elongation was at CMC

0.20 gram and sorbitol 5 ml with an average of

39.44%, while the smallest biodegradable

plastic elongation was at 0 gram CMC treatment

and 2 ml sorbitol at 13.89%. This shows the

value of elongation has increased along with the

addition of CMC and sorbitol concentrations.

CMC has high gel strength. The use of CMC in

larger amounts causes better water-binding

ability thus providing a gel matrix which can

increase percent elongation.

3.7. Young's Modulus

Young's modulus is obtained by comparing stress and strain. In biodegradable plastic with the addition of CMC, the amount of modulus of young is varied. Young modulus calculation results obtained the largest Young modulus value is 5.56 MPa and the smallest Young modulus value is 0.553 MPa. Based on ANOVA analysis showed the influence of the addition of CMC and sorbitol gave significant results at α <0.05 on Young's modulus produced. The interaction of the combination of the two factors also had a significant effect on α <0.05 so that further tests were carried out by DMRT (Duncan Multiple Range Test). Based on DMRT test results obtained for the CMC factor that the treatment 0, 0.20 and 0.40 grams give a more significant effect on the modulus of Young biodegradable plastic while the treatment of 0.30 grams does not give a more significant effect on the modulus value Young Significant influences are indicated by those in the second subset. However, the inter treatments did not have a significantly different effect because α> 0.05. As for the sorbitol factor treatment 2 3, and 4 mL gives a more significant effect compared to the 5 mL treatment. However, between treatments did not have a significantly different effect.

Figure 7. Graph of Young's Modulus

Biodegradable Plastic Due to Addition of CMC

Based on the graph shows that Young's

modulus of biodegradable plastic is the largest

average in the treatment of 0 gram CMC and

sorbitol 2 ml, with an average of 5.52 MPa,

while Young's modest biodegradable plastic is

the smallest average in CMC treatment of 0.30

gram and 4 ml sorbitol, with an average of 0.62

MPa. Young's modulus value is directly

proportional to the value of tensile strength.

3.8. Compressive Strength

The compressive strength obtained from

the measurement results of biodegradable

plastic samples ranged from 0.06 kgf to 0.47

kgf. The average compressive strength is 0, 27

kgf. Based on ANOVA analysis, the effect of

adding CMC and sorbitol gave significant

results at α <0.05 on the compressive strength

produced. The interaction of the combination of

the two factors also had a significant effect on α

<0.05 so that further tests were carried out by

DMRT (Duncan Multiple Range Test). Based

on the DMRT test that has been obtained, the

results for the CMC addition factor show that 0

and 0.20 gram treatments have a more

significant influence on the compressive

strength value of biodegradable plastics

compared to 0.30 and 0.40 gram treatments that

are in the second subset. However, the inter

treatment did not have a significantly different

effect. Whereas the addition factor of sorbitol

treatment 3 and 5 mL gives a more significant

effect compared to treatment 2 and 4 mL.

However, between treatments gave

significantly different effects on the treatment

of sorbitol 2 and 4 ml α = 0.05.

Figure 8. Graph Biodegradable Plastic

Compressive Strength (kgf) Due to the addition of

CMC (g) and sorbitol (ml)

0.00

2.00

4.00

6.00

0 0.2 0.3 0.4

You

ng'

s M

od

ulu

s (M

Pa)


Sorbitol 2 ml

Sorbitol 3 ml

Sorbitol 4 ml

Sorbitol 5 ml

0

0.1

0.2

0.3

0.4

0.5

0 0.2 0.3 0.4Co

mp

ress

ive

Stre

ngh

(K

gf)


sorbitol 2ml

sorbitol 3ml

sorbitol 4 ml

sorbitol 5 ml


P-ISSN:2356-3109 E-ISSN 2356-3117 63

Based on the graph shows that the

greatest compressive strength of biodegradable

plastic is at CMC treatment of 0 grams and

sorbitol 2 ml, with an average of 0.45 kgf, while

the smallest compressive strength of

biodegradable plastic is at CMC treatment of

0.40 grams and sorbitol 5 ml, namely with an

average of 0.15 kgf. This shows the value of

compressive strength decreased with increasing

concentrations of CMC and sorbitol. This is due

to CMC in the form of a small size molecule

that is between the starch chains, such as the

position of sorbitol. The effect of the surfactant

position can result in a decrease in

intermolecular interactions between starch

molecules, increase free space between the

starch chains, and increase polymer mobility.

As a result of these effects, the integrity of the

matrix structure of the film decreases and the

impact on the compressive strength of the edible

film decreases. Brandelero et al. (2010) added

that edible films containing surfactants had

lower compressive strength values than without

surfactants. The decrease in compressive

strength can be related to the increase of free

space between adjacent starch chains. This is in

accordance with Santoso (2012), that the more

addition of CMC in plastics increases the

compressive strength.

3.9. Biodegradability

Biodegradation testing is carried out using Effective Microorganism 4 (EM4). The results showed the greatest biodegradable value at 0.30 gram CMC and 4ml Sorbitol that is equal to 94.41%. While the smallest biodegradable value at the addition of 0 grams and 2ml sorbitol is equal to 29.13%. The average value of biodegradable plastic is 23.87%. Based on ANOVA analysis showed the influence of the addition of CMC and both factors gave significant results at α <0.05 on the biodegradable produced. The addition of sorbitol did not have a significant effect on α> 0.05 so that further tests were carried out DMRT (Duncan Multiple Range Test). Based on the DMRT test that has been done, it is obtained the results for the addition of CMC factors that the treatment of 0.30 and 0.40 grams gives a more significant effect on the biodegradable value compared to treatments 0 and 0.20 grams which are in the second subset. However, the inter treatment did not have a significantly different effect. Whereas the addition factor of sobitol treatment 2 and 4 mL

gives a more significant effect than treatment 3 and 5 mL. However, between treatments gave significantly different effects on the treatment of sorbitol 2 and 4 ml α = 0.05.

Figure 9. Graph of Biodegradable (%) Due to the

addition of CMC (g) and sorbitol (ml).

Based on the picture shows the greatest

biodegradable value at 0.30 gram CMC and 4ml

Sorbitol that is equal to 82.81%. While the

smallest biodegradable value at the addition of

0 grams and 2ml sorbitol is equal to 29.13%.

The average value of biodegradable plastic is

58.9447%. The rate of biodegradation of

biodegradable plastics increases with the

addition of CMC which can be seen in Fig.

According to Hasanah (2016), the addition of

CMC actually increases the hydrophilic nature

of the plastic produced. As a result, plastic has

a high level of humidity. A good biodegradable

plastic that has strong mechanical properties,

but also environmentally friendly (high

biodegradability).

3.9.1. SEM (Scanning Electron Microscopy)

Tests carried out on biodegradable

plastics that have the highest and lowest tensile

strength values. The samples tested were at 0

gram CMC mass and 2ml Sorbitol which were

the best treatment and 0.40 gram CMC mass

and 5ml sorbitol using 500x magnification.

Picture 1, Biodegradable Plastic structure with the

addition of CMC 0 g and Sorbitol 2 ml (a).

Biodegradable Plastic structure with the addition of

0.40 grams of CMC and sorbitol 5 ml

a b

0%

20%

40%

60%

80%

100%

0 0.2 0.3 0.4Bio

deg

rad

able

(%

)


sorbitol 2ml

sorbitol 3ml

sorbitol 4ml

sorbitol 5ml


64

SEM test results show that the microscopic

surface of biodegradable plastic with the

addition of CMC 0 gram and sorbitol 2 ml

surface morphology is smoother, whereas on

biodegradable plastic with the addition of CMC

0.40 gram and sorbitol 5 ml surface morphology

is rougher. This is not in accordance with

Tondang's research (2018), which states that the

surface morphology is more close where the

addition of CMC affects the surface structure of

the film. The higher the concentration of CMC

added by surface morphology, the closer it is

because CMC is often used as an emulsifier to

improve texture appearance. This result is likely

due to an uneven mixing process.

3.9.2. FTIR (Fourier Transform Infrared

Spectroscopy)

Infrared spectroscopic analysis aims to

determine the functional groups of organic and

inorganic compounds. Tests carried out on

biodegradable plastics that have the highest and

lowest tensile strength values. The samples

tested were at 0 gram CMC mass treatment and

2ml Sorbitol which was the best treatment and

0.40 gram CMC mass and 5ml sorbitol

treatment.

Figure 10, The spectrum of biodegradable plastics

with the addition of CMC concentration of 0.40

grams and the addition of 5 ml Sorbitol

Figure 11, The spectrum of biodegradable plastics

with the addition of CMC concentration 0 grams

and the addition of 2 ml Sorbitol

Based on Figures 11 and 12 show that

with the variation of the addition of CMC and

the addition of sorbitol appear several

vibrational peaks. The functional group of CO

alcohol appeared at the peak of 1062.78 cm-1,

CO ether which was at the peak of 1166.93 cm-

1, CO carboxylic acid which was at the peak of

1340.53 cm-1, CO ester which was at the peak

of 1062, 78 cm-1. At a wavelength of 2100-

2260 cm-1 which indicates the functional group

C = C Alkuna which is at the peak of 2146.77

cm-1. At a wavelength of 3200-3600 cm-1,

there is a functional group of hydrogen bonds

with an absorption peak at the number 3342.64.

FTIR test results in the form of functional

groups can be used as an indicator that the

plastic produced can still be degraded. This is in

accordance with the opinion of Setiawan (2014)

that in addition to hydroxide (OH) groups other

functional groups contained in plastics are

carbonyl (CO) groups and ester groups, so that

by having these functional groups plastic films

can be degraded. In the results of the FTIR test

conducted in this study obtained ester

functional groups, the resulting plastic film can

be degraded.

4. CONCLUSIONS

From the research that has been done with

the basic ingredients of starch uwi tuber

(Dioscorea alata) with the addition of CMC and

sorbitol plasticizer, it can be concluded that :

1. In the process of making biodegradable

plastics from Uwi tubers with the addition

and plasticizer of sorbitol as a whole the

plastic is produced from a variety of clear

colored treatments, the surface is slightly

rough, transparent, sticky and easy to stick if

in contact with other objects. The average

thickness of the plastic is 71.36 µm and the

average moisture content is 14.54%.

2. The concentration of the addition of CMC

and sorbitol plasticizer on bidegradable

plastic affects the mechanical properties of

tensile strength, elongation, modulus young

and compressive strength. the best tensile

strength value on the addition of cmc 0 gram

and sorbitol 2 ml is equal to 76.66 MPa, the

best elongation value at the addition of CMC

is 0.20 gram and sorbitol 5 ml is equal to

39.44%, the best young modulus value is at

adding cmc 0 gram and sorbitol 2 ml which


P-ISSN:2356-3109 E-ISSN 2356-3117 65

is 5.52 MPa and the lower the compressive

strength value is 0.150 kg / cm2.

3. Concentration of 0.40 gram CMC addition

and sorbitol 5 ml plasticizer on

biodegradable plastic affect biodegradability

of biodegradable plastic that is degraded

plastic at 7 days.

5. REFERENCES

Anggraini, Meilan. 2016. Pengaruh Konsentrasi

Carboxy Methyl Cellulose (Cmc) dan

Lama Penyimpanan Pada Suhu Dingin

Terhadap Stabilitas Dan Karakteristik

Minuman Probiotik Sari Buah Nanas.

Bandar Lampung: Universitas

Lampung

Hapsari, Ratri Tri. 2014. Prospek Uwi Sebagai

Pangan Fungsional dan Bahan

Diversifikasi Pangan. Buletin Palawija

No. 27

Hasanah, Y. R., Umi.U.K., Endang.W.,

Haryanto. 2016. Pengaruh Penambahan

Cmc (Carboxy Methyl Cellulose)

Terhadap Tingkat Degradibilitas Dan

Struktur Permukaan Plastik Ramah

Lingkungan. Simposium Nasional

Teknologi Terapan. Purwokerto:

Universitas Muhammadiyah

Purwokerto

Hikmah, Nurul. 2015. Pemanfaatan Limbah

Kulit Pisang Ambon (Musa

Paradisiacal) Dalam Pembuatan Plastik

Biodegradable Dengan Plasticizer

Gliserin. Palembang: Politeknik Negeri

Sriwijaya

Jabbar, Uhsnul Fatimah. 2010. Pengaruh

Penambahan Kitosan Terhadap

Karakteristik Plastik biodegradable

Dari Pati Kulit Kentang (Solanum

Tuberosum. L). Makassar: UIN

Alauddin Makassar

Nurhayati, S. W., Dwi K., Yuni T.N. 2012.

Pengaruh Penambahan Sorbitol Dan

Kalsium Karbonat Terhadap

Karakteristik Dan Sifat Biodegradasi

Film Dari Pati Kulit Pisang. Molekul.

Vol:7(1). Hal: 75

Purwanti, Ani. 2010. Analisis Kuat Tarik dan

Elongasi Plastik Kitosan Terplastisasi

Sorbitol. Jurnal Teknologi. Vol: 3(2).

Hal: 102

Rahayu, Astria Pengesti. 2016. Kajian

Karakteristik Edible Film Pati Hanjeli

(Coix Lacyma–Jobi L.) Dengan

Pengaruh Konsentrasi Pemlastis

Sorbitol Dan Konsentrasi Penstabil

Cmc. Bandung: Universitas Pasundan

Rifaldi, Anugerah, Irdoni Hs, Bahruddin. 2017.

Sifat dan Morfologi Plastik

biodegradable Berbasis Pati Sagu

dengan Penambahan Filler Clay dan

Plasticizer Gliserol. Jom FTEKNIK.

Vol:4(1). Hal: 3

Santoso, B., Filli.P., Basuni.H., Rindit.P., 2012.

Perbaikan Sifat Mekanik Dan Laju

Transmisi Uap Air Edible Film Dari

Pati Ganyong Termodifikasi Dengan

Menggunakan Lilin Lebah dan

Surfaktan. Agritech. Vol: 32(1). Hal:

11-12

Setiawan, H., Musthofa L, dan Masruroh. 2014.

Optimasi Plastik Biodegradable

Berbahan Jelarut (Marantha

arundinacea L) dengan Variasi LLDPE

untuk Meningkatkan Karakteristik

Mekanik. Jurnal Keteknikan Pertanian

Tropis dan Biosistem Vol. 2(2). Hal:

128

physicochemical characterization of biodegradable plastic

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