Hydrophobic modification of mesh spunlace nonwoven for medical dressing contact layer

The contact layer of traditional medical dressing is easy to adhere to the new wound granulation tissue, which brings the deficiency of secondary wound injury. This work assumed that low-cost and soft mesh spunlace nonwoven was used as medical dressing contact layer. After micro-nano SiO2 modification, polydimethylsiloxane (PDMS)/n-heptane were uniformly sprayed on the surface of materials. PDMS modification was studied by using the three-factor three-level orthogonal experiment. The results showed that when the PDMS concentration was 1%, the heat treatment temperature and time were 120°C and 12 h respectively, material possessed the optimal hydrophobicity and its water contact angle (CA) was 151.0 ± 1.1°. Meanwhile, the hydrophobicity, microstructure, thermogravimetry, composition, tensile mechanics, adhesion resistance and durability of materials with/without treatment were compared. It was proved that PDMS was indeed grafted onto the material and could effectively improve the hydrophobicity in coordination with micro-nano SiO2 without affecting the mesh structure of material. The machine direction (MD) and cross-machine direction (CD) strength of material decreased but the elongation increased slightly. The MD and CD peeling energy was 129.7 ± 33.9 J/m2 and 98.1 ± 38.3 J/m2, respectively. Moreover, the water CA of material modified by micro-nano SiO2/PDMS was still 139.4 ± 1.4° after 10 friction stroke tests, indicating that the modified material possessed the great durability. Overall, this study can provide the research basis for the development of anti-adhesion medical dressing contact layer.