The Effects of Functionality of the Organifier on the Physical Properties of Polyurethane Rigid Foam/Organified Nanosilica

Abstract

3-Aminopropyltriethoxysilane (APTS) was used as coupling agent on the nanosilica surface and its effects on the physical properties of polyurethane rigid foam were compared with nanosilica modified with n-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAP). Characterization and investigation of properties were done by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, dynamic mechanical analysis and thermomechanical analysis. Also, the tensile properties were evaluated. In the case of nanocomposite based on APTS poor static mechanical properties and better dynamic mechanical properties were reported as compared with nanocomposite based on AEAP. Thus, AEAP with two functional groups reinforced the interfacial area and weakened the bulk matrix by disruption of the stoichiometry ratio.

The influence of nano‐silica on the thermal conductivity of polyurethane foam

“…In comparison with other previous reports, the same tendency was also observed for the influence of different amounts of nano‐silica on the morphology of PUF 34,37 . According to Engin Burgaz, 35 the good dispersion of nanoparticles can help to increase the number of nucleation sites per unit volume in the PUF matrix leading to the formation of cells with smaller sizes and elevation of cell density.…”

“…Meanwhile, the cellular morphology have not been improved in the case of 0.2, and 0.25 %Wt nano‐silica. This result is explained that the appropriate nano‐silica particles act as extra nucleation sites during foaming process which can lead to diminish the average cell size and also to obtain a more uniform distribution of cell size 34,35 …”

“…This result is explained that the appropriate nano-silica particles act as extra nucleation sites during foaming process which can lead to diminish the average cell size and also to obtain a more uniform distribution of cell size. 34,35 Besides that, the interactions between the surface of nano-silica and PUF chains (Figure 4) can lead to a delay in the pore opening during cell growth. 1,36,39 Therefore, this process will take a little longer, giving the cell wall time to stabilize.From Figure 5, it can be seen that the density of PUF increased from 47.92 to 66.95 kg/m 3 by increasing the content of nano-silica from 0 to 0.45 %wt.…”

“…In comparison with other previous reports, the same tendency was also observed for the influence of different amounts of nano-silica on the morphology of PUF. 34,37 According to Engin Burgaz, 35 the good dispersion of nanoparticles can help to increase the number of nucleation sites per unit volume in the PUF matrix leading to the formation of cells with smaller sizes and elevation of cell density. Therefore, in this study, based on the good cellular structure of sample PUF -0.35, it can be concluded that 0.35%wt of nano-silica was the suitable contents which can be used to reinforce in PUF.…”

An Investigation into the Effects of Different Nanoclays on Polyurethane Nanocomposites Properties

“…Researchers showed that the use of a small amount of modified nanoclays and production of polyurethane-clay nanocomposite causes enhancement in mechanical and thermal properties, gas barriers and some other properties of such polymers remarkably [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] . The preparation of polyurethane-clay nanocomposites via in situ polymerization method has been the issue of many researches in past years [25,26,30,[40][41][42][43] .…”