Development and physical-chemical properties of pectin film reinforced with spent coffee grounds by continuous casting

The ever-growing environmental concerns over the unrestricted fossil sources exploitation for non-biodegradable materials production has stimulated research on alternative renewable resources. The pectin films (HDM) were incorporated in different concentrations of spent coffee grounds (SCG) (5-20% w/w HDM) aiming at developing biodegradable films and the use of an underutilized resource. The films were obtained by continuous casting. The chemical composition, morphology, thermal stability, barrier and mechanical properties (traction and puncture), and functional groups were investigated. Overall, SCG showed sound dispersibility and good interaction with the polymer matrix. The addition of SCG resulted in important pectin-based film properties changes, allowing an increase in color and thermal stability. SCG incorporation significantly improved the water vapor permeability rate improving or at least preserving the physicochemical properties.