Performance and Preparation of Styrene-Butadiene Copolymer Modified Polypropylene Matte Films

The demand for high-performance polypropylene (PP) films in high-end packaging applications has been growing rapidly. However, Traditional polypropylene (PP) films are limited in application by their inadequate mechanical strength, heat-sealing performance, and matte properties. Hence, in this study, styrene-butadiene copolymer-modified polypropylene (PP) matte films using styrene-butadiene copolymer (SB) as a modifier were successfully prepared. A comprehensive characterization of the films’ optical, mechanical, thermal, and processing properties was conducted using specialized instrumentation. Capillary rheometry revealed that the melt viscosity of the PP/SB blends decreased with increasing shear rate, demonstrating typical pseudoplastic behavior. Differential scanning calorimetry (DSC) showed single melting and crystallization peaks, indicating excellent compatibility between PP and SB. The optimal performance was achieved with 7.00 wt% SB, resulting in a film with a light transmittance of 92.08%, a haze of 66.40%, and a gloss of 3.63 GU. This formulation also yielded more uniform tensile strength and elongation in both longitudinal and transverse directions, and reduced the heat-sealing temperature to 101 °C, significantly lower than the 111 °C required for pure PP. Overall, the SB-modified PP films exhibited excellent mechanical strength, enhanced heat sealability, and superior matte properties, highlighting their significant potential for high-end packaging applications.