Characterization of Calotropis gigantiea plant leaves biomass-based bioplasticizers for biofilm applications

Abstract

The present surge in environmental consciousness has pushed for the use of biodegradable plasticizers, which are sustainable and abundant in plant resources. As a result of their biocompatibility and biodegradability, Calotropis gigantiea leaf plasticizers (CLP) serve as viable alternatives to chemical plasticizers. First time, the natural plasticizers from the Calotropis leaves were extracted for this study using a suitable chemical approach that was also environmentally friendly. The XRD results showed a reduced crystallinity index of 20.2 % and a crystalline size of 5.3 nm, respectively. TGA study revealed that the CLP has good thermal stability (244 °C). Through FT-IR study, the existence of organic compounds in CLP can be investigated by key functional groups such as alcohol, amine, amide, hydrocarbon, alkene, aromatic, etc. Further the presence of alcoholic, amino, and carboxyl constituents was confirmed by UV investigation. SEM, EDAX analysis, and AFM are used to examine the surface morphology of the isolated plasticizer. SEM pictures reveal rough surfaces on the CLP surface pores, which makes them suitable for plasticizing new bioplastics with improved mechanical properties. Poly (butylene adipate-co-terephthalate) (PBAT), a biodegradable polymer matrix, was used to investigate the plasticization impact after the macromolecules were characterised. The biofilm PBAT/CLP had a thickness of 0.8 mm. In addition, the reinforcement interface was examined using scanning electron microscopy. When CLP is loaded differently in PBAT, the tensile strength and young modulus change from 15.30 to 24.60 MPa and from 137 to 168 MPa, respectively. CLP-reinforced films demonstrated better surface compatibility and enhanced flexibility at a loading of 2 % when compared to pure PBAT films. Considering several documented characteristics, CLP may prove to be an excellent plasticizer for resolving environmental issues in the future.

Keywords: Biofiller; Biofilm; Biomass valorization; Biomaterial; Bioplasticizer; Calotropis gigantiea.

Fig. 1

Extraction process of plasticizer based on Calotropis gigantiea leaves.

Fig. 2

FT-IR spectroscopy of the CLP.

Fig. 3

(a&b). Proposed chemical structure of CLP biomass (a) 3D view (b).

Fig. 4

UV–visible spectroscopy of the CLP macromolecules.

Fig. 5

The XRD spectra of bioplasticizer obtained from C. gigantiea leaves.

Fig. 6

TGA/DTG curves and (b) Coats-Redfern plot of CLP.

Fig. 7

(a–d) AFM analysis of Calotropis gigantiea plasticizer.

Fig. 8

(a–e) Scanning electron microscopic pictures of Calotropis gigantiea plasticizer at different magnification.

Fig. 9

(a–c) Particle size study of Calotropis gigantiea plasticizer.

Fig. 10

(a & b) EDS analysis of CLP.

Fig. 11

The plasticization effect of CLP plasticizer in PBAT matrix.

Fig. 12

Photo image of the biofilm enhanced with CLP plasticizer: a pure PBAT film; b PBAT/2 % reinforced biofilm with CLP plasticizer; c Validation of pure PBAT film's elasticity; d Flexibility evaluation of the biofilm reinforced with PBAT/2 % CLP plasticizer; e, g SEM images of PBAT biofilm at magnifications of 100 and 500; f, h SEM images of biofilm-PBAT with 2 % CLP plasticizer at 100× and 500× magnification.

Fig. 13

Changes in Tensile strength of neat PBAT film and PBAT/CLP films.

Fig. 14

Relationship between the Young's modulus and different loading of PBAT/CLP/biofilm.