Compatibility induced gamma radiation of Agar/PBAT blends: Impact on material properties

Agar and polybutylene adipate-co terephthalate (PBAT) blend pellets were prepared by melt-extrusion with a high agar composition. The resulting plastic pellets were treated with gamma radiation to induces crosslinking and compatibilized the blending. The blending was irradiated in various doses, which was 10 kGy, 30 kGy, and 50 kGy. The effect of gamma irradiation on the plastic pellet were studied in terms of chemical structure, thermal properties, tensile properties, water resistivity and biodegradability. The irradiation 30 kGy increases the tensile strength from 3.21 MPa to 4.51 MPa, implying successful modification with radiation. The melting temperature (Tm) increased by irradiation doses from 91 °C to 110 °C. The crosslinking reaction of gamma irradiation causes the improved mechanical and thermal properties of irradiation agar/PBAT pellets. The water resistivity decreased, causing the formation of hydrophobic groups in the agar/PBAT pellet after irradiation. It is revealed that the 30 kGy irradiation dose is the optimum dose of radiation as it increases the tensile strength and decreases the water sensitivity significantly. The gamma irradiation reduced degradation with microbial growth from 82,91% to 75,88%, resulting in an improved antibacterial activity. These results show that gamma radiation can improve the properties of agar/PBAT plastic pellets and potentially be used as an antibacterial packaging.