Hydrolytic Co-condensation of Phenyltriethoxysilane with γ-Aminopropyltriethoxysilane in the Presence of Sodium Dodecyl Sulfate

Abstract

ABSTRACT:The hydrolytic co-condensation of hydrophobic phenyltriethoxysilane (PTES) and hydrophilicaminopropyltriethoxysilane (APS) under basic catalysis in the presence of sodium dodecyl sulfate (SDS) was investigated. Copolymer particles were influenced significantly by APS/PTES molar ratios, total monomer and SDS concentration. Amino group content of the copolymer was determined by element analysis and back titration. Scanning electron micrographs revealed the morphologies of the copolymer particles. FT-IR, solid state 29 Si NMR and TGA were used to characterize the copolymer. [DOI 10.1295/polymj.38.220] KEY WORDS -Aminopropyltriethoxysilane / Phenyltriethoxysilane / Sodium Dodecyl Sulfate / Hydrolytic Co-condensation / Copolymer Particles / Poly(phenylsilsesquioxane) (PPSQ) from the hydrolytic condensation of phenyltriethoxysilane exhibits outstanding thermal stability, good solubility in common organic solvents and fine electric insulting properties, 1,2 but its compatibility and reactivity with other polymers are not good enough. Poly(aminopropylsilsesquioxane) (PASQ) from the hydrolytic condensation of APS has been developed rapidly as a precursor to organic/inorganic hybrid polymers, 3 as starting material of a two-dimensional polysiloxane complex 4 and as a core for starburst dendrimers due to reactive amino groups, 5 but it is highly hygroscopic. Many properties of polylsilsesquioxanes can be modified by combining two or more RSiO 3=2 components (R is hydrogen or any alkyl, alkylene, aryl, arylene, or their organo-functional derivatives).6,7 The co-condensation method enables better control of the density of functional groups, then control of properties. It is expected that the co-condensation of PTES and APS will yield novel functional silsesquioxanes and the hybrid silsesquioxane will combine the advantages of PPSQ with APSQ. Tunney's patent claimed the preparation of such a poly(aminopropyl/phenylsilsesquioxane) (PAPSQ) by the hydrolytic co-condensation and its use as a precursor of organic/inorganic hybrid materials by imidization or amidation, 8 but no experimental details or characterization data were supplied. Their scheme under acid catalyst employs expensive tetrahydrofuran (THF) as co-solvent and isolation and purification is complicated. PAPSQ has been investigated in a Stöber-like method in our laboratory, 9 but some shortcomings such as low amino group contents and large particle diameter are insuperable from the method. This paper presents a useful alternative for the control of particle size and amino content of the copolymer, and provides easy access to a polysilsesquioxane copolymer with a relatively high degree of functionality. Anionic surfactant SDS was used, which has been shown effective in controlling the size of poly(phenylsilsesquioxane) 10 and poly(phenyl/methylsilsesquioxane) particles.11 Spheroidal copolymer particles with high amino group content are prepared by the hydrolytic co-condensation of hydrophobic PTES and hydrophilic APS in the presence of SDS. Knowledge of the...

High Performance Miscible Polyetherimide/Bismaleimide Resins with Simultaneously Improved Integrated Properties Based on a Novel Hyperbranched Polysiloxane Having a High Degree of Branching

“…The above statement can be further proved by the 29 Si NMR spectrum of AHBSi as shown in Figure . There is a distinct chemical shift at −68.79 ppm, which represents the dendritic unites O 1.5 Si(CH 2 ) 3 NH 2 , while the nearby smaller peaks arise from the incompletely condensed oligomers . The overlaid peaks from −59.55 to −61.02 ppm are attributable to linear units including NH 2 (CH 2 ) 3 SiOC 2 H 5 O and NH 2 (CH 2 ) 3 SiOHO; while the peaks around −53.89 ppm are assigned to the terminal groups including NH 2 (CH 2 ) 3 Si(OH) 2 O 0.5 , NH 2 (CH 2 ) 3 SiOHOC 2 H 5 O 0.5 , and NH 2 (CH 2 ) 3 Si(OC 2 H 5 ) 2 O 0.5 .…”

Synthesis and characterization of soluble and meltable poly(aminopropyl/phenylsilsesquioxane)

“…PAPSQ microparticles have been investigated by our group in stöber method [8] and emulsion copolymerization [9] . Tunney's patent claimed a preparation method of PAPSQ catalyzed by acid with tetrahydrofuran (THF) in water as co-solvent, and the use of PAPSQ as a precursor of inorganic-organic hybrid materials by imidization or amidation [10] , but no experimental details or characterization data were supplied.…”

Fire-Resistant and Hierarchically Structured Elastic Ceramic Nanofibrous Aerogels for Efficient Low-Frequency Noise Reduction

“…As shown in Figure b, the B–N stretching vibration and B–N bending vibration of h -BN were confirmed by the peaks at around 1375 and 746 cm –1 , receptively . The peak that appeared around 2931 cm –1 in the spectrum of SBA was ascribed to the −NH 2 group in APS and no evidence for the ethoxy groups was found, implying the hydrolysis of APS during the fabrication process . In the XRD spectrum, the diffraction peaks at 26.7, 41.6, 43.9, 50.2, and 55.1° correspond to the (002), (100), (101), (102), and (004) planes of h -BN, respectively .…”