Effects of the Addition of LiCI, LiCIO^sub 4^, and LiCF^sub 3^S0^sub 3^ Salts on the Chemical Structure, Density, Electrical, and Mechanical Properties of Rigid Polyurethane Foam Composite

摘要

The effect of the incorporation of several lithium salts on the electrical and mechanical properties of polyurethane rigid (PUR) foams was investigated. Different amounts of lithium chloride (LiCI), lithium Perchlorate (LiCIO^sub 4^), and lithium trifluoromethanesulfonate (LiCF^sub 3^SO^sub 3^) were added to the polyuretanic precursor. The salts affected the cellular microstructures and consequently the mechanical properties of the composite. Composite foams containing an amount of LiCI greater than 2 wt% showed low-surface resistivity (~10^sup 6^ ohm), whereas the LiCIO^sub 4^ and LiCF^sub 3^SO^sub 3^ composites showed, in all range of filler percentage analyzed, high-surface resistivity values (~10^sup 11^ ohm). This behavior was related to the different interactions between PUR and lithium salts, as confirmed by FTIR/Attenuated Total Reflectance analysis. Only the LiCI was able to create a motion of the ions Li+ and Cl- along the polyurethanic chains, because LiCI was completely dissociated. On the contrary, LiCIO^sub 4^ and LiCF^sub 3^SO^sub 3^ that affected the macromolecular structure of the polymeric network did not permit the formation of polyurethanic channels, where the ions could move, thus creating a charge motion. [PUBLICATION ABSTRACT]