Synthesis, Characterization, and Mechanical Performance Evaluation of PET‐Based Packaging Films Reinforced With Surface‐Functionalized Rice Husk Nanosilica and Phthalate‐Modified Starch

ABSTRACT This work highlights the conversion of PET, in combination with phthalated starch and modified nanosilica, into an environmentally friendly, biodegradable polymer blend. The surface‐functionalized nanosilica and phthalate‐modified starch undergo a good dispersion in the PET matrix. The high surface area (2.87 m 2 /g) and low particle size (9.87 μm) of the produced starch phthalate enhance its capability to form a homogeneous blend with PET. The produced blended sheets were extensively characterized by FTIR, SEM, XRD, and TGA analysis. SEM study investigates that on the addition of starch phthalate, the surface texture gets highly improved, leading to better compatibility with other materials in the matrix. Due to better binding properties, the interfacial tension gets reduced, which ultimately reduces the phase separation. XRD study reveals major peaks, which justify the crystalline nature of starch phthalate blended PET. FTIR analysis demonstrated that starch phthalate and nanosilica were successfully incorporated into polyolefin blends, indicating successful structural alteration. TGA showed that adding starch phthalate to PET lowers its thermal stability and decomposition temperature, suggesting that the modified composites are more biodegradable. Among different compositions, the best ratio of starch phthalate, modified nanosilica, and PET was found to be 8:0.6:32, having tensile strength 36 MPa, tear strength of 10.6 N/mm, and Young's modulus of 960 MPa. The produced blend can act as a superior packaging alternative for maintaining a sustainable environment.