Preparation and characterization of CO₂/O₂ selective facilitated transport films by coating polyvinyl alcohol/polyethylene glycol/aminated sodium lignosulfonate on TiO₂/ZnO‐modified LDPE

Abstract

A novel facilitated transport film was prepared by coating polyvinyl alcohol (PVA)/polyethylene glycol (PEG)/aminated sodium lignosulfonate on TiO2/ZnO‐modified low‐density polyethylene (LDPE). Monoethanolamine (MEA), diethanolamine (DEA), ethylenediamine (EDA), diethylenetriamine (DETA), tetramethylpiperidine amine (TEMP), and acrylamide (AM) were selected to modify sodium lignosulfonate (Ls) for enhancing the selectivity and permeability of CO2/O2. The fabricated Ls were characterized by fourier transform infrared (FTIR), thermogravimetric test (TG), and scanning electron microscopy (SEM). The CO2 permeability and CO2/O2 selectivity were improved with the increase in the amount of amine groups. Compared with the addition of Ls modified by alcohol amine, the composite film has higher selectivity to CO2 after the addition of DETA‐Ls or TEMP‐Ls. The selectivity of the 1:3:3EDA/MEA‐Ls‐g‐AM composite film reached 13.7, and CO2 permeability increased by 5.54 times. The storage test also demonstrated that the composite films have better freshness retention ability. As a result, modified LDPE coated by PVA/PEG/aminated Ls has the potential as an active modified atmosphere packaging material.