摘要:
A particulate water absorbent contains a water absorbent resin as a main component, the water absorbent resin being a crosslinked polymer of a water-soluble unsaturated monomer. The water absorbent resin is particular in shape and contains particles of a particle size in a range of not less than 106 μm and less than 850 μm in an amount of not less than 90 mass percent with respect to the total mass of the water absorbent resin contained in the particulate water absorbent. The particulate water absorbent has a first salt concentration absorption index of not less than 0.60 as measured by a formula below when ion exchange water is used as an aqueous solution of a constant salt concentration: (salt concentration absorption index)=(absorbency against a pressure of 4.83 kPa with respect to the aqueous solution of a constant salt concentration)/(absorbency against no pressure with respect to the aqueous solution of a constant salt concentration).
摘要:
The invention has an object to provide a catalyst for polymerizing or copolymerizing an α-olefin, catalyst constituent thereof, and method of polymerizing α-olefins with the catalyst, for production of α-olefin polymers or copolymers with high hydrogen response, high polymarization reaction rate, high stereoregularity and excellent melt fluidity. The invention discloses a catalyst constituent of the catalyst for polymerizing or copolymerizing an α-olefin, represented by Formula 37 or 38: Si(OR1)3(NR2R3)Formula 37 (where in Formula 37, R1 is a hydrocarbon group with 1 to 6 carbon atoms; R2 is a hydrocarbon group with 1 to 12 carbon atoms or hydrogen; and R3 is a hydrocarbon group with 1 to 12 carbon atoms) RNSi(OR1)3Formula 38 (where in Formula 38, R1 is a hydrocarbon group with 1 to 6 carbon atoms; and RN is a cyclicl amino group).
摘要:
The invention has an object to provide a catalyst for polymerizing or copolymerizing an α-olefin, catalyst constituent thereof, and method of polymerizing α-olefins with the catalyst, for production of α-olefin polymers or copolymers with high hydrogen response, high polymarization reaction rate, high stereoregularity and excellent melt fluidity. The invention discloses a catalyst constituent of the catalyst for polymerizing or copolymerizing an α-olefin, represented by Formula 37 or 38: Si(OR1)3(NR2R3) Formula 37 (where in Formula 37, R1 is a hydrocarbon group with 1 to 6 carbon atoms; R2 is a hydrocarbon group with 1 to 12 carbon atoms or hydrogen; and R3 is a hydrocarbon group with 1 to 12 carbon atoms) RNSi(OR1)3 Formula 38 (where in Formula 38, R1 is a hydrocarbon group with 1 to 6 carbon atoms; and RN is a cyclicl amino group).
摘要:
A (polycyclic secondary-amino)dialkoxysilane favorably employable as a catalyst for polymerization of &agr;-olefin can be prepared by reacting tetrachlorosilane, or a mono(C1-C8)alkyltrichlorosilane with a polycyclic secondary-amine in a non-hydrous, non-alcoholic organic solvent in the presence of a hydrogen chloride-trapping reagent, to produce a (polycyclic secondary-amino)chlorosilane and reacting the (polycyclic secondary-amino)chlorosilane with an alkali metal alkoxide or an alkaline earth metal alkoxide in the presence of a lower alcohol.
摘要:
This invention provides a process by which a polymer having a hydroxyl group at both terminals can be easily obtained with a cheap price and good efficiency from a wide field of vinyl-based monomers including polar ones. The process is arranged in such a manner that the polymerization of a vinyl-based monomer (a) is performed in the presence of an alcohol (b) having no addition-polymerization reactivity by using an initiator (c) consisting essentially of a peroxide and, on this occasion, at least one of catalysts (d) selected from a group consisting of an organic sulfonic acid compound having no addition-polymerization reactivity and an inorganic acid is further used and a reactor does not substantially contain any component other than the (a), (b), (c) and (d).