Preparation and characterization of stable DQ silicone polymer sols

Hayami, Ryohei; Nishikawa, Izumi; Hisa, Takayuki; Nakashima, Hiroaki; Sato, Yohei; Ideno, Yuzuko; Sagawa, Tadashi; Tsukada, Shinya; Yamamoto, Kazuki; Gunji, Takahiro

doi:10.1007/s10971-018-4839-z

Cited by 9 publications

(10 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The adsorption bands due to υSi-H (2139 cm − 1 ), δCH 3 (approximately 1255 cm − 1 ), δSi-Me (approximately 1155 cm − 1 ), υCC (970 cm − 1 ), and ρSi-Me (903 cm − 1 ) were observed, indicating the completion of the silylation process [12,16]. The absorption bands due to υ as CH 3 (approximately 2977 cm − 1 ), υ s CH 2 (approximately 2930 cm − 1 ), υ s CH 3 (approximately 2897 cm − 1 ), υCO (approximately 1100 cm − 1 ), υ as Si-O-Si (approximately 1080 cm − 1 ), ρCH 3 in Si-CH 3 (860 cm − 1 ), υ s Si-O-Si (795 cm − 1 ), and δCCO and δSiOSi (approximately 455 cm − 1 ) were also observed [11,12,17,18]. Figure S1 presents the mass spectra of the CLs.…”

Section: Characterization Of Si-h Terminated Oligosiloxane Cross-link...mentioning

confidence: 84%

“…Minor signals associated with Q 1 (OEt) 2 (OH) (around − 86 ppm), cyclic Q 2 (OH) 2 (-90.6 ppm), Q 3 -OH (-99.6 to -101 ppm), and Q 3 -OEt (-101.5 to -103 ppm) were also observed [10,[12][13][14]. Small signals due to 5-or 6-membered cyclic Q 2 (OEt) 2 (-95.4 ppm) were evident in the hydrolysis condensates of TEOS and OETS before silylation [11,15]. Following silylation, complex signals attributed to the dimethylsiloxyl group emerged between − 1 to -5 ppm [12].…”

Section: Characterization Of Si-h Terminated Oligosiloxane Cross-link...mentioning

confidence: 94%

“…Absorption bands corresponding to υ as CH 3 (2962 cm − 1 ), υ s CH 2 (2903 cm − 1 ), δCH 3 in Si-CH 3 (1258 cm − 1 ), υ as Si-O-Si (1075 cm − 1 ), υO-Si-O (1010 cm − 1 ), ρCH 3 in Si-CH 3 (860 cm − 1 ), both υSi-C and υ s Si-O-Si (785 cm − 1 ), and υSi-C (700 cm − 1 ) were observed [11,12,17,18]. Notably, no absorption band attributed to υSi-H (2139 cm − 1 ) was detected [12,16].…”

Section: Properties Of Pdms Cross-linked With Si-h Terminated Teos He...mentioning

confidence: 96%

“…No soluble fraction was detected in the swelling test, which validates that all PDMS CLs underwent reaction and crosslinking. The degree of swelling is inversely proportional to the extent of cross-linking; as the cross-linking degree increases, the swelling degree diminishes [11,[39][40][41]. As the content of CL increased, there was a corresponding decrease in the swelling degree.…”

Section: Properties Of Pdms Cross-linked With Si-h Terminated Teos He...mentioning

confidence: 99%

See 3 more Smart Citations

Preparation and Properties of PDMS elastomer cross-linked with hydrolyzate of TEOS, HEDS, or OETS oligomers: influence of cross-linker structure

Sato,

Hayami,

Yamamoto

et al. 2023

Preprint

Self Cite

View full text Add to dashboard Cite

Linear oligoethoxysiloxanes were hydrolyzed, and the resulting hydrolyzates were dimethylsilylated to produce Si–H terminated ethoxysiloxanes (CLs). These CLs were characterized using gel permeation chromatography, nuclear magnetic resonance, and Fourier-transform infrared spectroscopy. The results indicated the formation of highly condensed cyclic siloxanes, four-membered cyclic siloxanes, and linearly condensed cyclic siloxanes when derived from tetraethoxysilane, hexaethoxydisiloxane, and octaethoxytrisiloxane, respectively. The CLs were subsequently reacted with vinyl-terminated polydimethylsiloxane in the presence of the Karstedt catalyst to yield PDMS elastomers, which are comprised of di- and quadra-functional silicones. Tests for transmittance, thermal properties, tensile strength, and swelling in toluene were conducted to assess the impact of the molecular weight and microstructure of the CLs on the final products. As the number of silicon atoms in the linear oligoethoxysiloxanes increased, there was a noticeable rise in the secant modulus and a reduction in the degree of swelling. These findings suggest that the structure of PDMS elastomers can be tailored by varying the structure of the linear oligosiloxanes used as a cross-linking agent.

show abstract

Section: Characterization Of Si-h Terminated Oligosiloxane Cross-link...mentioning

confidence: 84%

Section: Characterization Of Si-h Terminated Oligosiloxane Cross-link...mentioning

confidence: 94%

Section: Properties Of Pdms Cross-linked With Si-h Terminated Teos He...mentioning

confidence: 96%

Section: Properties Of Pdms Cross-linked With Si-h Terminated Teos He...mentioning

confidence: 99%

See 2 more Smart Citations

Preparation and Properties of PDMS elastomer cross-linked with hydrolyzate of TEOS, HEDS, or OETS oligomers: influence of cross-linker structure

Sato,

Hayami,

Yamamoto

et al. 2023

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hexaethoxydisiloxane (HEDS) and octaethoxytrisiloxane (OETS) were synthesized according to previous report [10]. KOH powder was prepared as follows: KOH pellets were dissolved in EtOH and reprecipitated with THF followed via drying under vacuum at 90 °C for 3 h [11]. Dimethylvinylsiloxy terminated polydimethylsiloxane (PDMS-Vi) was prepared by the ring-opening polymerization of D 4 with KOH powder followed by silylation using chlorodimethylvinylsilane, and M w and M w /M n of PDMS-Vi were 49,000 Da and 3.3, respectively.…”

Section: Methodsmentioning

confidence: 99%

Preparation and properties of PDMS elastomer cross-linked with hydrolyzate of tetraethoxysilane, hexaethoxydisiloxane, and octaethoxytrisiloxane: influence of cross-linker structure

Sato,

Hayami,

Yamamoto

et al. 2023

J Sol-Gel Sci Technol

Self Cite

View full text Add to dashboard Cite

Ethoxysilanes were hydrolyzed, and the resulting hydrolyzates were dimethylsilylated to produce Si–H terminated oligosiloxanes (CLs). These CLs were characterized using gel permeation chromatography, nuclear magnetic resonance, and Fourier-transform infrared spectroscopy. The results indicated the formation of highly condensed cyclic siloxanes, four-membered cyclic siloxanes, and linearly condensed cyclic siloxanes when derived from tetraethoxysilane, hexaethoxydisiloxane, and octaethoxytrisiloxane, respectively. The CLs were subsequently reacted with vinyl-terminated polydimethylsiloxane in the presence of the Karstedt catalyst to yield PDMS elastomers, which are comprised of di- and quadra-functional silicones. Tests for transmittance, thermal properties, tensile strength, and swelling in toluene were conducted to assess the impact of the molecular weight and microstructure of the CLs on the final products. As the number of silicon atoms in the ethoxysilanes increased, there was a rise in the secant modulus and a reduction in the degree of swelling. These findings suggest that the structure of PDMS elastomers can be tailored by varying the structure of the ethoxysilanes used as a cross-linking agent. Graphical Abstract

show abstract

Mild Synthesis of a Dimethoxy‐Terminated Siloxane through a Ring‐Opening Reaction

Liang

et al. 2022

ChemistrySelect

View full text Add to dashboard Cite

Alkoxy-terminated siloxanes can be used as coupling agents to improve the properties of materials, and they are also widely used in organic synthesis. Herein, a method to synthesize a dimethoxy-terminated siloxane by the ring-opening reaction of 2,4,6-trimethyl-2,4,6-trivinyl-1,3,5,2,4,6-trioxatrisilinane (D 3 -Vi) and methanol under mild condition was reported. The reaction does not require strong acids, strong bases or transition metal catalysts. The structure of the product was confirmed by 1 H-NMR, 29 Si-NMR and mass spectrometry (MS). The Gibbs free energy change of the reaction under the implicit solvent model was calculated by density functional theory (DFT), which proved the feasibility of the reaction. The calculation discussed the two-step mechanism of the ring-opening reaction. One methanol attacked D 3 -Vi to form a monomethoxy-terminated product, and then another methanol attacked from the other side to form a dimethoxy-terminated product. The calculated reaction rate constants of the reaction at different temperatures indicate that the reaction has a tunneling effect, especially at low temperatures. Considering the complex reaction of D 3 -Vi and methanol explained why the calculated rate constants at low temperatures were large but the ringopening reaction could hardly occur. The mild synthesis can promote the application of alkoxy-terminated silicones.

show abstract

Preparation and characterization of stable DQ silicone polymer sols

Cited by 9 publications

References 51 publications

Preparation and Properties of PDMS elastomer cross-linked with hydrolyzate of TEOS, HEDS, or OETS oligomers: influence of cross-linker structure

Preparation and Properties of PDMS elastomer cross-linked with hydrolyzate of TEOS, HEDS, or OETS oligomers: influence of cross-linker structure

Preparation and properties of PDMS elastomer cross-linked with hydrolyzate of tetraethoxysilane, hexaethoxydisiloxane, and octaethoxytrisiloxane: influence of cross-linker structure

Mild Synthesis of a Dimethoxy‐Terminated Siloxane through a Ring‐Opening Reaction

Contact Info

Product

Resources

About