Migration phenomena of surfactants in polyethylene film

Temperature-dependent desorption of surfactants in LLDPE blend films

“…This phenomenon indicates that the surfactant was continuously migrating out of the film in the water bath. The room‐temperature measurement at 25 °C was similar to the result obtained in our previous report 16. In addition, the spectral behavior of the specimens stored at 40 °C exhibited a similarity to the behavior at 25 °C.…”

“…In general, the I t / I ∞ value gives an initial slope that is accepted as the diffusion coefficient ( D ) at the early stage of desorption and then reaches the saturated level. This sort of observation was also obtained in the previous study,16 except for specimen II stored at 50 °C (the value of I t / I ∞ slightly decreased after the initial slope was obtained). The same behavior was observed for specimens III and IV, as drawn in Figures 8 and 9, respectively; after an initial slope was obtained, the value of I t / I ∞ reached the saturation level for the specimens examined between 25 and 50 °C.…”

“…The latter may be affected because of the incorporation of a large amount (20 wt %) of EAA. As discussed in a previous report,16 the blocking effect of EAA may have retarded the migration of the surfactant. In addition, at 40 and 50 °C, the 1739 cm −1 peak abruptly decreased for the 1st day and then gradually decreased during the rest of the experimental duration.…”

“…However, in more complex polymeric systems, the diffusion is affected by a number of structural factors, such as crystallization, chain stiffness, and crosslinking 12–15. In a semicrystalline polymer, the diffusion coefficient is often modified by both the immobilization factor (Ψ) and the path blocking factor ( B ) 14, 16…”

“…In our previous study,16 the diffusion coefficient of sorbitan palmitate (SPAN‐40) in a linear low‐density polyethylene (LLDPE) blend system was calculated at room temperature, and it was reduced because of the incorporation of poly(ethylene acrylic acid) (EAA), which was used as a migration controller. In addition, it was reported that the diffusion kinetics followed Fickian behavior.…”