Polyethylene-octene elastomer/silica hybrids prepared by a sol-gel process using tetraethoxysiliane

Abstract

Abstract-In this study, new organic-inorganic hybrid composites were prepared by means of an in situ sol-gel process. The polymer used as the continuous phase was the metallocene polyethylene-octene elastomer (POE) or the acrylic acid grafted polyethylene-octene elastomer (POE-g-AA). The silica forming the inorganic phase was produced by the hydrolysis and condensation of tetraethoxysilane (TEOS) in polymers. Characterizations of POE-g-AA/ SiO 2 and POE / SiO 2 hybrids were performed by Fourier transform infrared (FT-IR) spectroscopy, 29 Si solid-state nuclear magnetic resonance (NMR) spectrometry,X-ray diffraction (XRD) spectroscopy, differentialscanning calorimetry (DSC), thermogravimetry analysis and Instron mechanical tester. We found that the POEg-AA/ SiO 2 hybrid could enhance the properties of the POE / SiO 2 hybrid, since the interfacial forces of the former are the covalent Si O C and hetero-associatedhydrogen bonds but the latter only has weaker hydrogen bonds. The result of 29 Si solid-state NMR spectra showed that Si atom coordination around SiO 4 units is predominantly Q 3 and Q 4 . It was also found that the POE-g-AA/ SiO 2 hybrid with 9 wt% SiO 2 gave the maximum value of tensile strength since excess particles might cause the separation between the organic and inorganic phases when the silica content was beyond this point.

Contribution of hydrogen and/or covalent bonds on reinforcement of natural rubber latex films with surface modified silica

“…This observation ensures that the esterification reaction occurs between the carboxylic group of MCA and silanol group of silica filler. Similar observation has been encountered by Ru Xia et al and other scientists in their studies of surface modification of silica . Young also reported a similar observation in his study on IR spectroscopy of carboxylic acids and their derivatives adsorbed on silica …”

Surface modification of silica with a hydrophilic polymer and its influence on reinforcement of natural rubber latex

“…It ensures the esterification reaction that occurs between the carboxylic group of the polymer and the silanol group of the silica filler. A similar observation has been encountered by Ru et al (2006) and other scientists in their studies of surface modification of silica (Wu & Liao, 2003;Tai et al, 2008;Xia et al, 2008b). Young (1969) also reported the same observation in his study on IR absorption on carboxylic acids and their derivatives adsorbed on silica.…”

Modification of biodegradable polylactide by silica and wood flour through a sol–gel process

“…In the latter, the peak at 1710 cm 21 was shifted to 1733 cm 21 due to the formation of ester groups through the reaction between carboxylic acid groups of PLA-g-AA and SiÀ ÀOH groups of SiO 2 network. 15,31 The absorbance of free SiÀ ÀOH groups appeared at a region, about 961 cm 21 in Figure 1(D) (labeled as isolated or free hydroxyl groups).…”

“…This new peak at 2y 5 18.28, which may be due to the formation of an ester carbonyl functional group as described in the discussion of FTIR analysis, was also reported by Wu and Liao. 31 Thermal stability of hybrids (DSC and TGA tests)…”