Preparation of dimer acid-based polyamide film by solution casting method and its properties optimization

The dimer acid-based polyamide (DAPA) was prepared by polymerization of dimer acid and ethylenediamine. And the film was prepared by the solution casting method, in which tetrahydrofuran was used as the solvent. Glycerol is introduced into the film by adding glycerol together with tetrahydrofuran and smearing it on the glassware before the film’s formation. The paper has evaluated the DAPA film packaging performance, which has rarely been studied, such as oxygen barrier property and optical properties. Through forming the film by the two means of adding glycerol, the paper has studied its property on the mechanic, morphology, oxygen barrier. The results of which show the differentiation of producing film in two ways. The tensile strength and elongation at break were increased by 80% and 228%. And the oxygen permeability was 0.00732 cm²/m²·dpa. The thermal processability of the film has been improved. Compared with other bio-based film, the DAPA film with glycerol solution has excellent mechanical properties, barrier property, and optical properties.