Table 3 Techniques used for characterization of PE biodegradation

FTIR

Functional groups on the surface

Keto-carbonyl index (I1715/I1565); Ester-carbonyl index (I1740/I1465); Vinyl-bound index (I1640/I1465);

Double bound index (I908/I1465);

C-O stretching (I1100)

[3, 6, 34, 38, 41, 74, 83, 93, 94, 105, 113]

Contact angle drop deposition

Hydrophobicity/hydrophilicity

Contac angle with water, Surface energy

[6, 91, 105]

FTIR/DSC/XRD

Crystallinity

Crystallinity; Melting temperature; Relative crystallinity; Lamellar thickness

[2, 76]

HT-SEC/GPC

Molecular weight distribution

Changes in the molecular weight

[38];

[41];

SEM/AFM

Surface topography

Molecular weight distribution topography

[6, 105]

Instron

Mechanical properties

Tensile strength; Strain energy;  % Elongation and extension

[8, 14, 18]

Gravimetric CO₂ evolution

Consumption of the polymer

Weight loss

[34, 74, 93]