It is known that NPMI and St still formed an alternating copolymer in such S-Poly multi-monomer systems, and MEA was a weak acceptor randomly introduced into the copolymer chain (9).
Figure 2 shows that the coating rate decreased significantly with decreasing temperature in the NPMI system.
There are several characteristic peaks of the NPMI unit in NPMI-coatings.
From the following data for 4FMI, NPMI and 3TMI-coatings, the percentage (mol %) of each element in the surface polymer structure is shown in Table 2.
This is consistent with the previous conclusion for the NPMI/St systems, which formed alternating copolymers with 1/1 ratio of NPMI and St units, as calculated from FTIR spectra (13).
A similar ratio of NPMI (or 3TMI) units to St units is formed in coatings from corresponding monomers.
In fact, the different percentage of MEA units found in these three coatings indirectly indicates the different reactivities of 4FMI, NPMI and 3TMI and St relative to MEA units.
Fluorinated S-Poly coatings were obtained by introducing two fluorinated monomers to replace NPMI in the previous NPMI/St/MEA/BMI system.