Degradable Plastic Composite Film—A Comparison …
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2.2.6 Characterization of the Film Before and After Degradation
Characterization of all the films was done by Scanning Electron Microscopy (SEM;
Model No. S3400N, VP SEM, Type- II, Hitachi, Japan) along with Fourier Transformed Infra-Red Spectroscopy (FTIR; Perkin Elmer l- Spectrum-2, Singapore)
before and after photocatalytic degradation in addition to biodegradation. SEM was
used for determining surface morphology whereas FTIR was used for functional
group study.
3 Results and Discussion
3.1 Isolation of PVC-Degrading Strains
22 morphologically different isolates were obtained from the collected soil sample.
Among these 22 isolates only 5 strains (FS1, FS2, FS3, FS4, and FS5) were able to
degrade plastic composite film comprising PVC, PCL, and ZnO. The present work
has been conducted by FS1 strain only and therefore FS1 is only identified.
3.2 Identification of Strain FS1
On the basis of 16 s rRNA gene sequencing method the FS1 strain was characterized
as Bacillus altitudinis. Highlights of the colony morphology are: irregular configuration and margin, rough surface with raised elevation; gram-positive spore forming
bacteria and can form pigment; spores are oval and centrally positioned. Growth
characteristics indicate its positive growth in the temperature range 15–50 °C, pH
range 5–9, and salt concentration of 3–9%. Biochemically they are positive in Casein,
gelatin hydrolysis, catalase, and Esculine hydrolysis.
3.3 Photodegradation and Biodegradation of Plastic
Composite Film
Maximum degradation obtained by photocatalysis was 17.8% after 120 min as it
is a fast process whereas after 25 days maximum 10% microbial degradation was
achieved because any biological process is actually a complex and slow process.
For comparison, blank experiments with PVC, PVC-ZnO composite, and PVC-PCL
composite films were subjected to the same experimental conditions (Figures not
shown). The observed data have been represented in Fig. 1a, b. Average intensity of
light was 341 × 100 lx in case of solar degradation. From Fig. 1a, b, it is observed
253
2.2.6 Characterization of the Film Before and After Degradation
Characterization of all the films was done by Scanning Electron Microscopy (SEM;
Model No. S3400N, VP SEM, Type- II, Hitachi, Japan) along with Fourier Transformed Infra-Red Spectroscopy (FTIR; Perkin Elmer l- Spectrum-2, Singapore)
before and after photocatalytic degradation in addition to biodegradation. SEM was
used for determining surface morphology whereas FTIR was used for functional
group study.
3 Results and Discussion
3.1 Isolation of PVC-Degrading Strains
22 morphologically different isolates were obtained from the collected soil sample.
Among these 22 isolates only 5 strains (FS1, FS2, FS3, FS4, and FS5) were able to
degrade plastic composite film comprising PVC, PCL, and ZnO. The present work
has been conducted by FS1 strain only and therefore FS1 is only identified.
3.2 Identification of Strain FS1
On the basis of 16 s rRNA gene sequencing method the FS1 strain was characterized
as Bacillus altitudinis. Highlights of the colony morphology are: irregular configuration and margin, rough surface with raised elevation; gram-positive spore forming
bacteria and can form pigment; spores are oval and centrally positioned. Growth
characteristics indicate its positive growth in the temperature range 15–50 °C, pH
range 5–9, and salt concentration of 3–9%. Biochemically they are positive in Casein,
gelatin hydrolysis, catalase, and Esculine hydrolysis.
3.3 Photodegradation and Biodegradation of Plastic
Composite Film
Maximum degradation obtained by photocatalysis was 17.8% after 120 min as it
is a fast process whereas after 25 days maximum 10% microbial degradation was
achieved because any biological process is actually a complex and slow process.
For comparison, blank experiments with PVC, PVC-ZnO composite, and PVC-PCL
composite films were subjected to the same experimental conditions (Figures not
shown). The observed data have been represented in Fig. 1a, b. Average intensity of
light was 341 × 100 lx in case of solar degradation. From Fig. 1a, b, it is observed