The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Junxiao Yang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of poly silmethylene s via ring opening polymerization of Benzocyclobutene functionalized disilacyclobutene and their low dielectric and thermal properties
Polymers for Advanced Technologies, 2017Co-Authors: Yawen Huang, Shengbo Zhang, Xiaonan Wei, Junxiao YangAbstract:In this work, Benzocyclobutene-introduced poly(silmethylene)s were synthesized by ring-opening copolymerization of Benzocyclobutene (BCB) functionalized disilacyclobutene with phenyldisilacyclobutene. The incorporation ratio of BCB was tailored by changing feeding ratio of 1,3-dimethyl-1,3-diBenzocyclobutene-1,3-disilacyclobutane and 1,3-dimethyl-1,3-diphenyl-1,3-disilacyclobutane, thus enabling the control of ultimate properties of cured resins. With increasing the incorporation ratios of BCB from 9.5 to 28.9 mol%, T5% of cured resins is improved from 404°C to 462°C, while the dielectric constant is decreased from 2.59 to 2.41 at 10 MHz. The excellent thermal stability and low-dielectric performance make such thermosets potential inter-layered or inter-lined low-dielectric media. Copyright © 2017 John Wiley & Sons, Ltd.
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Benzocyclobutene vinylphenyl introduced polycarbosilanes with low dielectric constant high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Benzocyclobutene/vinylphenyl-introduced polycarbosilanes with low dielectric constant, high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Synthesis and properties of cross-linkable polysiloxane via incorporating Benzocyclobutene
High Performance Polymers, 2014Co-Authors: Lu Yang, Ke Cao, Yawen Huang, Guanjun Chang, Fanghua Zhu, Junxiao YangAbstract:Benzocyclobutene (BCB), as a reactive group, was incorporated into the side chains of polysiloxane via platinum/carbon hydrosilylation reaction. The hydrosilylation reaction showed good tunability ...
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High temperature thermosets derived from Benzocyclobutene-containing main-chain oligomeric carbosilanes
Polymer, 2014Co-Authors: Ke Cao, Lu Yang, Yawen Huang, Guanjun Chang, Junxiao YangAbstract:Abstract A series of Benzocyclobutene-carbosilane thermosets derived from Benzocyclobutene-containing oligomeric silylenephenylene (PBSEPs) were synthesized. DSC analysis results demonstrated that the reaction of PBSEPs presumably took place within the temperature range of 200–350 °C. FT-IR, 1 H NMR and 13 C NMR results demonstrated that this exothermic reaction was attributed to a [4 + 2] cycloaddition. DSC results further revealed that benzocylcobutene linked with silylene exhibited lower exothermic temperature compared with that linked with Si(CH 3 ) 2 . Chemical simulation results attributed the lower temperature to lower steric hindrance and greater activity. DSC and TGA analysis of the thermosets showed high T g and thermostability, and good pyrolysis yield.
Maurice Santelli - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Unnatural Steroids Using the Bistro Strategy
SYNLETT, 2015Co-Authors: Philippe Maurin, Hélène Pellissier, Delphine Moraleda, Raphaël Rodriguez, Maurice SantelliAbstract:Lithium-mediated reductive dimerization of buta-1,3-diene in the presence of chloro(trimethyl)silane readily provides 1,8-bis(trimethylsilyl)octa-2,6-diene, commonly known as Bistro'. This bisallylsilane can react with various electrophilic reagents to give 1,1-disubstituted 2,5-divinylcyclopentanes, which are precursors of the D rings of steroids. After slight alterations, these precursors can be coupled with Benzocyclobutene derivatives. Heat induces ring opening of the Benzocyclobutene to form an o-xylylene that subsequently undergoes intramolecular cycloaddition with a vinyl substituent to form the skeleton of a new unnatural steroid, according to the A + D AD ABCD strategy. In this way, more than 250 steroids have been prepared, including 3-, 11-, 12-heterosteroids bearing a 17-vinyl group that can be readily modified to form a 17-acetyl or 17-(2-oxoethyl) group, as well as some steroid building blocks. The steroids were obtained in few steps from buta-1,3-diene and Benzocyclobutene derivatives in overall yields in excess of 25%. This powerful strategy, which has not yet been exhausted, paves the way towards various related synthetic pathways. 1 Introduction 2 Series A 3 Series B 4 Series C 5 Series D 6 Series E 7 X-Ray Crystallographic Data 8 Conclusion
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A very short synthesis of steroids from 1,3-butadiene and Benzocyclobutenes.
The Journal of organic chemistry, 2001Co-Authors: Pierre-yves Michellys, Philippe Maurin, Loïc Toupet, Hélène Pellissier, Maurice SantelliAbstract:Lewis acid mediated addition of 1,8-bis(trimethylsilyl)octa-2,6-diene (BISTRO) 1 to succinic anhydride led to spirolactone 2 [(+/-)-6,9-divinyl-1-oxaspiro[4.4]nonan-2-one]. Methoxycarbonylation followed by stereoselective alkylation by various Benzocyclobutenes afforded the substituted Benzocyclobutene steroid precursors 5. Thermolysis of 5 gave rise to steroids (+/-)-6 with a trans-anti-cis configuration in five steps and in a highly stereoselective manner. Modifications of the sequence allowed the preparation of steroids (+/-)-11 with trans-anti-trans configuration.
Yawen Huang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of poly silmethylene s via ring opening polymerization of Benzocyclobutene functionalized disilacyclobutene and their low dielectric and thermal properties
Polymers for Advanced Technologies, 2017Co-Authors: Yawen Huang, Shengbo Zhang, Xiaonan Wei, Junxiao YangAbstract:In this work, Benzocyclobutene-introduced poly(silmethylene)s were synthesized by ring-opening copolymerization of Benzocyclobutene (BCB) functionalized disilacyclobutene with phenyldisilacyclobutene. The incorporation ratio of BCB was tailored by changing feeding ratio of 1,3-dimethyl-1,3-diBenzocyclobutene-1,3-disilacyclobutane and 1,3-dimethyl-1,3-diphenyl-1,3-disilacyclobutane, thus enabling the control of ultimate properties of cured resins. With increasing the incorporation ratios of BCB from 9.5 to 28.9 mol%, T5% of cured resins is improved from 404°C to 462°C, while the dielectric constant is decreased from 2.59 to 2.41 at 10 MHz. The excellent thermal stability and low-dielectric performance make such thermosets potential inter-layered or inter-lined low-dielectric media. Copyright © 2017 John Wiley & Sons, Ltd.
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Benzocyclobutene vinylphenyl introduced polycarbosilanes with low dielectric constant high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Benzocyclobutene/vinylphenyl-introduced polycarbosilanes with low dielectric constant, high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Synthesis and properties of cross-linkable polysiloxane via incorporating Benzocyclobutene
High Performance Polymers, 2014Co-Authors: Lu Yang, Ke Cao, Yawen Huang, Guanjun Chang, Fanghua Zhu, Junxiao YangAbstract:Benzocyclobutene (BCB), as a reactive group, was incorporated into the side chains of polysiloxane via platinum/carbon hydrosilylation reaction. The hydrosilylation reaction showed good tunability ...
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High temperature thermosets derived from Benzocyclobutene-containing main-chain oligomeric carbosilanes
Polymer, 2014Co-Authors: Ke Cao, Lu Yang, Yawen Huang, Guanjun Chang, Junxiao YangAbstract:Abstract A series of Benzocyclobutene-carbosilane thermosets derived from Benzocyclobutene-containing oligomeric silylenephenylene (PBSEPs) were synthesized. DSC analysis results demonstrated that the reaction of PBSEPs presumably took place within the temperature range of 200–350 °C. FT-IR, 1 H NMR and 13 C NMR results demonstrated that this exothermic reaction was attributed to a [4 + 2] cycloaddition. DSC results further revealed that benzocylcobutene linked with silylene exhibited lower exothermic temperature compared with that linked with Si(CH 3 ) 2 . Chemical simulation results attributed the lower temperature to lower steric hindrance and greater activity. DSC and TGA analysis of the thermosets showed high T g and thermostability, and good pyrolysis yield.
Guanjun Chang - One of the best experts on this subject based on the ideXlab platform.
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Benzocyclobutene vinylphenyl introduced polycarbosilanes with low dielectric constant high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Benzocyclobutene/vinylphenyl-introduced polycarbosilanes with low dielectric constant, high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Synthesis and properties of cross-linkable polysiloxane via incorporating Benzocyclobutene
High Performance Polymers, 2014Co-Authors: Lu Yang, Ke Cao, Yawen Huang, Guanjun Chang, Fanghua Zhu, Junxiao YangAbstract:Benzocyclobutene (BCB), as a reactive group, was incorporated into the side chains of polysiloxane via platinum/carbon hydrosilylation reaction. The hydrosilylation reaction showed good tunability ...
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High temperature thermosets derived from Benzocyclobutene-containing main-chain oligomeric carbosilanes
Polymer, 2014Co-Authors: Ke Cao, Lu Yang, Yawen Huang, Guanjun Chang, Junxiao YangAbstract:Abstract A series of Benzocyclobutene-carbosilane thermosets derived from Benzocyclobutene-containing oligomeric silylenephenylene (PBSEPs) were synthesized. DSC analysis results demonstrated that the reaction of PBSEPs presumably took place within the temperature range of 200–350 °C. FT-IR, 1 H NMR and 13 C NMR results demonstrated that this exothermic reaction was attributed to a [4 + 2] cycloaddition. DSC results further revealed that benzocylcobutene linked with silylene exhibited lower exothermic temperature compared with that linked with Si(CH 3 ) 2 . Chemical simulation results attributed the lower temperature to lower steric hindrance and greater activity. DSC and TGA analysis of the thermosets showed high T g and thermostability, and good pyrolysis yield.
Lili Liu - One of the best experts on this subject based on the ideXlab platform.
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Benzocyclobutene vinylphenyl introduced polycarbosilanes with low dielectric constant high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.
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Benzocyclobutene/vinylphenyl-introduced polycarbosilanes with low dielectric constant, high temperature performance and photopatternability
Polymer, 2015Co-Authors: Lili Liu, Guanjun Chang, Yawen Huang, Cuijiao Zhao, Junxiao YangAbstract:Abstract With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of Benzocyclobutene/vinylphenyl-introduced polycarbosilanes (PVBCS) were synthesized by H2PtCl6 catalyzed ring-opening copolymerization of 4-(1-methylsilacyclobutyl) Benzocyclobutene (4-MSCBBCB) and 1-methyl-1-(4-vinylphenyl) silacyclobutane (1-MVPSCB). By directly introducing photo-active groups on the pendants of polycarbosilanes, the PVBCS was endowed with photopatternability without additionally using any photo-initiators or photo-crosslinkers. DSC and FTIR characterization demonstrated that the PVBCS was UV&thermally curable. The UV curing was conducted at ambient temperature and the thermally curing was performed above 200 °C. TGA curves of the cured PVBCS indicated that the 5% weight loss temperature is 473 °C, which is above the required temperature limit. The cured PVBCS also has low dielectric constant of 2.32–2.40 in the range of 1 k∼1 MHz. The high temperature performance and low-dielectric constant could be attributed to the polycarbosilane main-chain structure and the Benzocyclobutene-based cross-linked structure.