Preparation of highly efficient thermal management polyurethane foam coatings based on crosslinked modified phase change microcapsules: Integration of temperature regulation, flame retardancy, and antibacterial functions

Polyurethane (PU) foam, known for its lightweight nature, cushioning, shock absorption, and sound insulation properties, is an ideal material for automotive lightweighting and safety design. However, conventional PU foam has poor heat resistance and lacks active thermal management, flame retardancy, and antibacterial properties, which limits its application in high-performance areas such as new energy vehicles. Incorporating phase change materials (PCM) is an effective strategy for achieving active temperature regulation, but developing a PCM that is both heat-resistant and damage-resistant while simultaneously providing flame retardancy and antibacterial functions remains a significant challenge. To address this issue, a semi-interpenetrating polymer network (semi-IPN) was constructed through the integration of a multilayer graphene oxide (GO) crosslinked framework with polyethylene glycol (PEG). Subsequently, silica (SiO₂) was employed as an encapsulating shell to fabricate core-shell structured GO/PEG@SiO₂ phase change microcapsules in this study. These phase change microcapsules were subsequently integrated into water-based PU foam via coating and high-temperature foaming techniques, resulting in a microcapsule-modified foam coating. Experimental results indicate that, compared to conventional PU coating, the microcapsule-modified foam coating exhibits superior temperature regulation, with a maximum temperature difference of 32.9 °C. Moreover, the composite coating retains passive insulation properties while introducing active thermal regulation, and achieves synergistic flame retardancy (V-2 rating) and antibacterial functionality. This study offers a new strategy for designing high-performance, multifunctional automotive interior materials.