Preparation of SPEEK/PE Composite Membrane and Application in Lettuce Preservation
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
Spontaneous gas-regulated sulfonated polyetheretherketone (SPEEK)/polyethylene (PE) composite membranes were prepared. The effect of SPEEK with different sulfonation degree on gas permeability, moisture permeability and anti-fog properties of SPEEK/PE composite membranes were studied by a series of testing methods. Then, the SPEEK/PE composite membranes ware applied to preserve lettuce. The results showed that the permeability coefficient of different sulfonation degree of SPEEK/PE modified membranes for CO2 and O2 decreased slightly. The separation coefficient of SPEEK/PE composite membrane for CO2/O2 increased from 0.73 to 5.58. The moisture permeability of composite membrane was between 1.50×10-14 ~4.00×10-14 g·cm/(cm·s·Pa), which reduced by two orders of magnitude, compared to SPEEK membrane(between 2.00×10-12~2.46×10-12 g·cm/(cm·s·Pa). And the SPEEK/PE composite membran had good properties of anti-fog. The results of preservation experiment indicated that high sulfonation degree of SPEEK/PE composite membrane had good air-conditioning preservation effect on lettuce. Compared to ordinary PE group and blank group, the changes of the weight loss rate, chlorophyll content, total phenolic content, vitamin C content and soluble solid content of lettuce were reduced during the preservation process, and the preservation periods of composite membrane groups were extended by 12 days and 4 days respectively. Based on the preservation effect, at 4 ℃, SPEEK/PE composite film could maintain the content of CO2 and O2 in the packaging environment at 10.00%~12.00% and 4.00%~5.00% respectively, and extend the storage period of lettuce to 20 days.
