Enhancing flame retardancy, thermal stability, and superhydrophobic of paper through Na₂O·nSiO₂ and PDMS modification

Abstract The water absorption and flammability of paper pose significant challenges for its long-term effectiveness. In addressing these concerns, a paper modification strategy was proposed that synergistically incorporated superhydrophobicity and flame retardancy. This approach involved the formation of a micro or nano-level rough structure on the paper surface through sodium silicate modification. Subsequent modification with polydimethylsiloxane (PDMS) resulted in a functional paper, exhibiting excellent superhydrophobic properties. The water contact angle (WCA) and sliding angle (SA) of the modified paper reached 153.5° and 9°, respectively, exhibiting excellent self-cleaning ability and wear resistance. The results from TG–DTG analysis and cone calorimeter tests indicated that the superhydrophobic paper exhibited remarkable thermal stability and flame-retardant properties. These properties contributed to enhancing the safety of products during application. The comprehensive improvement in paper properties, including its superhydrophobicity, flame retardancy, and thermal stability, holds significant implications for expanding its application range and enhancing its overall utility.