A novel boron–silicon–alkynyl hybrid copolymer: Synthesis, characterization, heat resistance, and thermo-oxidative stabilities. (April 2017)

• Record Type: Journal Article
• Authors: Zhou, Qi; Zhou, Quan; Geng, Jie; Ni, Li Zhong
• Is Part Of: High performance polymers. Volume 29:Number 3(2017)
• Page Start: 249
• Page End: 256
• Publication Date: 2017-04
• Subjects: Boron–silicon–alkynyl hybrid -- curing -- heat resistance -- precursor for ceramics; Polymerization -- Periodicals; Polymers -- Periodicals; 547.7
• DOI: 10.1177/0954008316638134
• Languages: English
• ISSNs: 0954-0083

Abstract

A novel boron–silicon–alkynyl hybrid copolymer (BSD) was synthesized by condensation polymerization of 1, 3-diethynylbenzene with dichloromethylsilane and boron trifluoride etherate. Fourier transform infrared and 1 H-, 13 C-, and 29 Si-nuclear magnetic resonance spectroscopies were used to confirm the structures of the copolymers. Thermogravimetric analysis and differential scanning calorimetry showed that the polymer exhibited excellent heat resistance and thermo-oxidative stabilities under nitrogen and air. The cure cross-linking reaction mechanisms of the BSD were related to Diels–Alder intermolecular cyclization involving two C≡C bonds and hydrosilylation reaction between Si–H and C≡C bonds. TheT d 5 of the BSD was above 591°C and 530°C under nitrogen and air, respectively. The residues at 1000°C were above 88% under nitrogen and 25% in air. X-ray diffraction was used to study the formation of ceramics. The precursor for ceramics (β-SiC, α-SiC, and B4 C) was formed at 1600°C under an argon atmosphere. The thermo-oxidative stabilities of the copolymers were attributed to the existing organic groups of alkynyl and inorganic elements of silicon and boron.