Study On Fluorosilicone Polymer And Functional Organosilicone Compounds

Organosilicone materials are widely used in electrical,textile,medical,construction,machine owing to the excellent high and low temperature resistance,radiation resistance,corrosion resistance,electrical insulation,hydrophobic and so on.With the development of the times,the fact that organosilicone materials are expected to have higher performance to meet the demand of products,it drives the development of high-performance organosilicone material.Based on the previous research about the organosilicone materials,this paper has carried out the study on three parts:(1)Synthesis and characterization of fluorine-containing siloxanes,polysiloxane containing fluoroalkyl and prepared fluorosilicone rubber.The structures of the compounds,fluorine-containing siloxanes,polysiloxane containing fluoroalkyl are characterized by FT-IR,1H-NMR and 29Si-NMR.The optimum polymerization conditions of fluorosilane,the polymerization of fluorosilicone and the optimum vulcanization conditions are discussed respectivelly.The mechanical properties,aging resistance and solvent resistance of fluorosilicone rubber after vulcanization are investigated.The results show that the fluorine-containing allyl ether is linked to the tetramethylcyclotetrasiloxane by the method of hydrosilylation reaction,with the best conditions are nfluorine monomer: nsilicon monomer = 10: 1 and solvent amount is twice of the reaction system.The Si-H bond are completely disappeared on the provement of FT-IR?1H-NMR?29Si-NMR,and the yield of the product is more than 99%.The polysiloxane containing fluoroalkyl is prepared by ring-opening polymerization using the cyclic siloxane fluorine-containing.Polysiloxane prepolymer was prepared through ring-opening polymerization by tetramethylammonium hydroxide as a catalyst using octamethylcyclotetrasiloxane and tetravinyltetramethylcyclotetrasiloxane as the raw materials.When the concentration of tetramethylammonium is 0.03%,the molecular weight of the polymer is maximized.Polyfluorosiloxane vulcanization would complete under the effect of DBPH and DCP at 150~160? with 20~25min.The results show that the second stage vulcanization is beneficial to improvement of the mechanical properties of the rubber.(2)Comparison of the reactivity of polysiloxane oligomers containing hydrogen.The polysiloxane oligomers containing hydrogen are characterized by FT-IR,1H-NMR and 29Si-NMR.The hydrosilylation activity of polysiloxane oligomers containing hydrogen with different length of chain units is researched by the curing time and differential scanning calorimetry(DSC).The reaction activity of the series of polysiloxane oligomers containing hydrogen is confirmed by the method of determination of curing reaction time and DSC.For dimethylsilyl-terminated diphenylsiloxy groups with different number of chain units-Si(Ph)2-,the reactivity of the oligomer hydrosilylation decreases gradually with the number of chain unit-Si(Ph)2-increases.(3)Synthesis and characterization of branched polysiloxane terminated by vinyl.the branched polysiloxanes terminated by vinyl is synthesized by hydrolysising under acidic conditions and condensation equilibrium under alkaline conditions with the industrial by-product,dimethoxymethyphenylsilane(DMePh)/phenyltrimethoxysilane(TPh)as the raw materials.The branched polysiloxanes terminated by vinyl was successfully synthesized.It proved the required structure of product by FT-IR?1H-NMR?29Si-NMR,and the synthesis route is stable by adjusting the monomer ratio according to the different batches DT by-products monomer content.The synthetic product would be used as packaging glue,the results of application performance testing showed that the composites are excellent.