Ethylene–propylene copolymer/ordered polysilsesquioxane nanocomposites prepared via organic acid‐ or base‐catalyzed binary silica water‐crosslinking reactions

Abstract

BACKGROUND:In-situ silica sol-gel derived organic-inorganic hybrid materials, which comprise a vinyltrimethoxysilane-grafted ethylene-propylene copolymer (EPR-g-VTMS) and n-hexyltrimethoxysilane (HTMS), were successfully prepared in the presence of an organic acid and base catalyst. Benzenesulfonic acid (PhSO 3 H) and aniline (PhNH 2 ) were selected as the organic acid and base catalyst, respectively, to examine the progress and effect of progressive changes in the silane water-crosslinking reaction of EPR-g-VTMS/HTMS composites. RESULTS:The water-crosslinked EPR-g-VTMS/HTMS composites were characterized by means of attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), solid-state silicon-29 cross polarization/magic angle spinning-nuclear magnetic resonance ( 29 Si CP/MAS NMR), wide-angle X-ray scattering (WAXS), tensile strength, and field emission-scanning electron microscope (FE-SEM) measurements. CONCLUSION:These results revealed that the type of catalyst has a substantial influence on the nature of siloxane bands and eventually the physical tensile properties of the water-crosslinked EPR-g-VTMS/HTMS composites, which can be explained mainly on the knowledge of the traditional acid-and base-catalyzed silica sol-gel reaction. Moreover, the in-depth analysis for the PhNH 2 -catalyzed composites indicated the formation of ladder-type poly(n-hexyl silsesquoxane)s and the presence of the highly-ordered structure with a thickness equal to the length of two n-hexyl groups in all-trans conformation. In the present study, we demonstrated a potential for future design of highly-ordered silicate-based organic-inorganic hybrid nanocomposites.3/28

Dioxomolybdenum(VI) and dioxotungsten(VI) complexes: efficient catalytic activity for crosslinking reaction in ethylene‐vinyl acetate copolymer/alkoxysilane composites

“…According to the literature procedure, [25,26] the gel content measurements were carried out to evaluate the overall crosslinking reaction in the EVA/TEOS composite system. Briefly, crosslinked EVA/TEOS composite samples in a glass wool filter were put into boiling xylene for 12 hr in a Soxhlet extractor apparatus.…”

A comparative study on the preparation and physical properties of environmental friendly PMMA‐silica nano/sub‐micron‐scale hybrid latexes controlled by chelating agent

“…Figure 2 shows the solid‐state 13 C CP/MAS NMR spectra of NVS and MVS, which exhibited extra resonance peaks at chemical shifts 130.42 and 135.91 ppm, respectively. These peaks were attributed to the carbon signal from the vinyl group of VTMS [21, 22].…”

In situ binary sol–gel reaction of various trifunctional alkoxysilane in the silane‐grafted polyolefin matrix and its effect upon the mechanical properties

“…We recently investigated the water‐cross‐linking reaction of vinyltrimethoxysilane‐grafted ethylene‐propylene copolymer (EPR‐ g ‐VTMS) in the presence of various catalysts, and discussed that the type of catalyst affects the degree of cross‐linking and eventually the mechanical properties [30–34]. Herein, we propose a new organic–inorganic hybrid material design using the same EPR‐ g ‐VTMS matrix and various trifunctional methoxysilanes (RTMS).…”