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A series of poly[(methylsilylene ethynylenephenyleneethynylene)-co-(dimethylsilylene ethynylenephenyleneethynylene)]s were synthesized by the incorporation of various ratios of methylsilylene to dimethylsilylene units into the polymer chain backbone.The resultant copolymers were soluble in a variety of common organic solvents at room temperature.The copolymers were characterized by FT-IR,~1H-NMR,GPC,rheological analysis,differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA).The results showed that the copolymers exhibited good processability and cured at low temperatures like 200℃.The curing reactions involved in hydrosilylation of Si—H and alkyne groups and the polymerization of alkynes.Y_(d5)(5%weight loss) of the cured copolymers ranged from 629℃to 686℃,and the decomposition residues of cured copolymers at 1000℃ranged from 88.1%to 90.9%under nitrogen.Thermal stability of the copolymers increased with the introduction of methylsilylene units into polymer chains.The cured copolymers were sintered at 1450℃,and the results of X-ray diffraction analysis showed that β-SiC was formed in the sintered products.
A series of poly [(methylsilylene ethynylenephenyleneethynylene)] s were synthesized by the incorporation of various ratios of methylsilylene to dimethylsilylene units into the polymer chain backbone. The resultant copolymers were soluble in a variety of common organic solvents at room temperature. These copolymers were characterized by FT-IR, ~ 1H-NMR, GPC, rheological analysis, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results showed that the copolymers exhibited good processability and cured at low temperatures like 200 ° C. The curing reactions involved in hydrosilylation of Si-H and alkyne groups and the polymerization of alkynes. Y_ (d5) (5% weight loss) of the cured copolymers ranged from 629 ° C to 686 ° C, and the decomposition residues of cured copolymers at 1000 ° C ranged from 88.1% to 90.9% under nitrogen. The stability of the copolymers increased with the introduction of methylsilylene units into polymer chains. The cured copolymers were sintered at 1450 ° C, and the results of X-ray diffraction analysis analysis showed that β-SiC was formed in the sintered products.