Effects of the addition of LiCl, LiClO₄, and LiCF₃SO₃salts on the chemical structure, density, electrical, and mechanical properties of rigid polyurethane foam composite

Abstract

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 (LiCl), lithium perchlorate (LiClO4), and lithium trifluoromethanesulfonate (LiCF3SO3) 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 LiCl greater than 2 wt% showed low‐surface resistivity (∼106 Ω), whereas the LiClO4 and LiCF3SO3 composites showed, in all range of filler percentage analyzed, high‐surface resistivity values (∼1011 Ω). This behavior was related to the different interactions between PUR and lithium salts, as confirmed by FTIR/Attenuated Total Reflectance analysis. Only the LiCl was able to create a motion of the ions Li+ and Cl− along the polyurethanic chains, because LiCl was completely dissociated. On the contrary, LiClO4 and LiCF3SO3 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. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Recycling and recovery of PE‐PP‐PET‐based fiber polymeric wastes as aggregate replacement in lightweight mortar: Evaluation of environmental friendly application

“…An examination of CO stretching mode related to the mortar composites (Figure ) highlights that the peak shifted toward lower frequency as the amount of fiber plastic waste increased from 1453 cm −1 for M 0 to 1440, 1427, and 1407 cm −1 , respectively for M 10 , M 15 , and M 20 . The shift of this vibration peak may be attributed to the hydrogen interactions between the CO group of the mortar and the OH group of glycol unit, which is visible in the fiber waste .…”

“…To assess the effect of fiber plastic waste on the mortar, the absorption peaks of carbonate anion were used as analyte peaks. All spectra baselines were corrected by ensuring that the spectrum was zeroed at 1800 cm 21 where the baseline was relatively horizontal.…”

A novel underwater acoustically transparent material: Fluorosilicone polyester polyurethane

“…The sample size was φ = 90 × 20 mm 2 . [23][24][25] In addition, the peak at 1266 cm -1 was assigned to the stretching vibrations of the C─F bond in ─CF 3 ; this proved the existence of the ─CF 3 group in FSPU. φ is the diameter symbol, which represents the diameter of a cylinder, as shown in Figure 2(b).…”

Highly hydrophobic microporous low‐density polyethylene hollow fiber membranes by melt‐extrusion coupled with salt‐leaching technique

“…Such observations are in good agreement with tensile properties reported in the literature for porous polymeric membranes and rigid particle filled polymeric composites. [3,[22][23][24][25][26] …”

“…[23] Despite the importance of porous polymeric materials, little attention was given to the use of open-cellular foams prepared via salt leaching from polymer/salt composite matrix for membrane applications. However, the leaching process, which is the most important part of this technique, still remains noticeably untouched.…”