Preparation and performance study of PMMA-based SPNR composite films via emulsion polymerization

Natural medical latex products commonly encounter critical challenges during application, including poor tensile performance, inadequate strength, and insufficient biocompatibility. Additionally, their usage environments are often contaminated with pathogenic bacteria. Traditional antibacterial strategies typically rely on materials like pentachlorophenol and N-methylolacrylamide, but these substances increase user risks of allergies and other diseases. To address these limitations, this study synthesizes polymethyl methacrylate-polystyrene (PMMA-PS) and polymethyl methacrylate-chitosan oligosaccharide (PMMA-COS) nanoparticle emulsions via emulsion polymerization. Under conventional direct deposition methods, poor interfacial compatibility between the membrane materials causes extensive delamination of the deposited layer from the natural latex surface during long-term use, thereby deteriorating overall mechanical performance. To mitigate this, PMMA-PS is first blended with pre-vulcanized natural rubber latex (SPNR). The addition of PMMA-PS enhances film mechanical properties due to the excellent compatibility between PMMA-PS and PMMA-COS emulsions, which fosters a more stable phase structure during blending and deposition. Leveraging COS’s ability to improve surface antibacterial property, PMMA-COS dispersion is deposited onto PMMA-PS∼SPNR blend films, yielding PMMA-COS/PMMA-PS∼SPNR composite films with enhanced mechanical properties, physical stability, and reduced safety concerns. This research provides scientifically valuable findings and quantitative evidence for improving the antibacterial and mechanical performance of natural medical latex products (e.g., condoms, medical gloves) and the stability of nanocoatings on their surfaces.