摘要:
A method for producing a polybutadiene, which comprises subjecting 1,3-butadiene to cis-1,4 polymerization, and subsequently subjecting a resultant in the resulting polymerization system to syndiotactic-1,2 polymerization, the method being characterized in that there is added, after the polymerization, a halogen acid or halogen acid salt.
摘要:
Disclosed is a process for producing a conjugated diene polymer having a very high content of cis-1,4 structures by using an yttrium compound-containing catalyst that is relatively easy to handle and has a high activity. Specifically disclosed is a process for producing a conjugated diene polymer containing cis-1,4 structures at a ratio of 99% or higher, which is characterized by polymerizing a conjugated diene in the presence of a catalyst produced from (A) a specific yttrium compound, (B) an ionic compound consisting of a non-coordinating anion and a cation, and (C) an organoaluminum compound.
摘要:
Disclosed is a process for producing a conjugated diene polymer having a very high content of cis-1,4 structures by using an yttrium compound-containing catalyst that is relatively easy to handle and has a high activity. Specifically disclosed is a process for producing a conjugated diene polymer containing cis-1,4 structures at a ratio of 99% or higher, which is characterized by polymerizing a conjugated diene in the presence of a catalyst produced from (A) a specific yttrium compound, (B) an ionic compound consisting of a non-coordinating anion and a cation, and (C) an organoaluminum compound.
摘要:
A method for producing a polybutadiene, which comprises subjecting 1,3-butadiene to cis-1,4 polymerization, and subsequently subjecting a resultant in the resulting polymerization system to syndiotactic-1,2 polymerization, the method being characterized in that there is added, after the polymerization, a halogen acid or halogen acid salt.
摘要:
Provided by using a catalyst containing an yttrium compound is conjugated diene polymer with very low solution viscosity, improved workability, high degree of branching, and high content of cis-1,4 structures. Also provided is a rubber composition utilizing the polymer and allowing excellent dispersion of reinforcing agent. According to a method of manufacturing a conjugated diene polymer characterized by polymerizing a conjugated diene at 50 to 120° C. in the presence of a catalyst obtained from (A) an yttrium compound, (B) an ionic compound consisting of a non-coordinating anion and a cation, and (C) an organoaluminum compound, the conjugated diene polymer has the following characteristics that: (1) a ratio (Tcp/ML1+4) between a 5 wt % toluene solution viscosity (Tcp) measured at 25° C. and a Mooney viscosity (ML1+4) at 100° C. is 0.1 to 1.2; and (2) a content of cis-1,4 structures is 80% or higher, and a content of 1,2 structures is lower than 5%.
摘要:
Provided by using a catalyst containing an yttrium compound is conjugated diene polymer with very low solution viscosity, improved workability, high degree of branching, and high content of cis-1,4 structures. Also provided is a rubber composition utilizing the polymer and allowing excellent dispersion of reinforcing agent. According to a method of manufacturing a conjugated diene polymer characterized by polymerizing a conjugated diene at 50 to 120° C. in the presence of a catalyst obtained from (A) an yttrium compound, (B) an ionic compound consisting of a non-coordinating anion and a cation, and (C) an organoaluminum compound, the conjugated diene polymer has the following characteristics that: (1) a ratio (Tcp/ML1+4) between a 5 wt % toluene solution viscosity (Tcp) measured at 25° C. and a Mooney viscosity (ML1+4) at 100° C. is 0.1 to 1.2; and (2) a content of cis-1,4 structures is 80% or higher, and a content of 1,2 structures is lower than 5%.
摘要:
The present invention is to provide a process for producing piperonal which comprises continuous three steps of: (A) an addition reaction step wherein 1,2-methylenedioxybenzene and glyoxylic acid are reacted to form 3,4-methylenedioxymandelic acid in the presence of a strong acid, (B) an extraction step wherein an organic solvent is then added to a reaction mixture and the mixture is neutralized with a base to extract 3,4-methylenedioxymandelic acid in an organic solvent layer, and separating the organic solvent layer and an aqueous layer, and (C) an oxidation reaction step wherein the aqueous layer is removed and the organic solvent layer is concentrated, and then, nitric acid is added to a concentrate, and the 3,4-methylenedioxymandelic acid and nitric acid are reacted to form piperonal.
摘要:
Silicon carbide-based fine particles containing an electrically conducting inorganic substance and a electromagnetic wave absorbing material, which are fine particles comprising a particle inner portion of a silicon carbide-based material and a surface layer formed of an electrically conducting inorganic substance mainly comprising carbon, wherein a gradient layer with the compositional ratio of the electrically conducting inorganic substance gradiently increasing toward the particle surface is present and the thickness of the electrically conducting inorganic substance gradient layer is from 1 to 500 nm. The electromagnetic wave absorbing material of the present invention can selectively absorb a electromagnetic wave of 1 to 300 GHz in a wide band.
摘要:
Silicon carbide-based fine particles containing an electrically conducting inorganic substance and a electromagnetic wave absorbing material, which are fine particles comprising a particle inner portion of a silicon carbide-based material and a surface layer formed of an electrically conducting inorganic substance mainly comprising carbon, wherein a gradient layer with the compositional ratio of the electrically conducting inorganic substance gradiently increasing toward the particle surface is present and the thickness of the electrically conducting inorganic substance gradient layer is from 1 to 500 nm. The electromagnetic wave absorbing material of the present invention can selectively absorb a electromagnetic wave of 1 to 300 GHz in a wide band.
摘要:
A process for preparing 3,4-methylenedioxymandelic acid by reacting 1,2-methylenedioxybenzene with glyoxylic acid in the presence of a strong acid and of at least one substance selected from the group consisting of an aprotic organic solvent and 100 to 1200 ml of an organic acid per kg of 1,2-methylenedioxybenzene.
摘要翻译:一种通过1,2-亚甲二氧基苯与乙醛酸在强酸和至少一种选自非质子有机溶剂和100至1200ml 有机酸/ kg 1,2-亚甲二氧基苯。