Abstract
Polyurea (PUA) is a type of protective coating material with excellent performance. However, the water vapor barrier property of PUA is not very ideal and need to be improved. In this study, PUA film was coated by polyvinylidene chloride (PVDC) by casting of PVDC emulsion, to improve its water vapor barrier property. A polydopamine layer was introduced between the PUA and PVDC layers to provide good adhesion performance. The morphology, chemical structure and performance of the films were characterized by scanning electron microscope, fourier transform infrared spectroscopy, water contact angle analysis, and water vapor transmission rate (WVTR) tests. It is indicated that, with the thickness of the PVDC coating increasing, WVTR decreases almost linearly. When the thickness of the PVDC coating is 5.2 μm, WVTR is 12.58 g/m2·day and water vapor permeability (WVP) is 1345.65 g·µm/m2·day·kPa. The WVTR and WVP of PVDC coated PUA is greatly reduced by 74.3% and 73.9% respectively, compared to that of pure PUA film. The adhesion of the PVDC coating on the PUA surface was evaluated through the cross-cut testing method. It is shown that the adhesion is strong enough to resist the pasting and peeling by adhesive tape.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
