78results about How to "High polymerization reactivity" patented technology

The invention relates to a preparation method of polypropylene wax. The method is characterized in that a liquid phase bulk polymerization technology is used, a supported metallocene catalyst is used, hydrogen is adopted as a molecular weight regulator, and a granular polypropylene wax product is directly obtained through catalyzing liquid propylene polymerization. The propylene polymerization reaction activity is not lower than 1000 times/h. The method has the characteristics of simple operation and high polymerization reaction activity, and the molecular weight of the polypropylene wax product obtained in the invention is adjustable and has narrow distribution.

A nonaqueous electrolyte secondary battery, comprising a positive electrode having a positive-electrode active material layer reversibly inserting and extracting lithium ions on a positive-electrode current collector, a negative electrode having a negative-electrode active material layer reversibly inserting and extracting lithium ions on a negative-electrode current collector, and a nonaqueous electrolyte solution, wherein at least one of the positive and negative electrodes has a film on the surface and at least one of the positive electrode, the negative electrode and the nonaqueous electrolyte solution contains a nitrogen-containing cyclic compound. Such a nonaqueous electrolyte secondary battery is superior in high-temperature storage stability allowing preservation of favorable discharge rate even after high-temperature storage.

The present invention discloses an ethylene tetrapolymerization catalyst composition, which comprises a diphosphine ligand represented by a formula I, a transition metal compound, an aluminum-containing co-catalyst, water and an organic solvent, wherein R1, R2, R3 and R4 are respectively and independently selected from alkyl, cycloalkyl and aryl, and R5 is selected from alkyl, cycloalkyl and aryl. The invention further discloses a method for carrying out an ethylene tetrapolymerization reaction by using the catalyst composition. The formula I is defined in the specification.

An object is to provide a liquid crystal compound having high polymerization reactivity, a high conversion ratio and high solubility in a liquid crystal composition, a polymerizable composition containing the compound, a liquid crystal composite prepared using the composition, and a liquid crystal display device having the composite. A solution is a polymerizable compound represented by formula (1).

In formula (1), P¹ and P² are identically group (P-1), (P-2) or (P-3), and in formula (P-1), M is hydrogen, fluorine, —CH₃ or —CF₃;

S¹ and S² are a single bond, alkylene having 1 to 6 carbons or the like; a1, a2 and b1 are 0, 1, 2, 3 or 4, and a sum of al and a2 is 4; ring A¹ is naphthalene, anthracene or phenanthrene; and ring A² is cyclohexyl, phenyl, naphthyl, anthracenyl or phenanthrenyl; and Z¹ is a single bond, —CO—, —COO— or the like.

The invention provides the usage of using the benzoic acid stannous as catalyst. The invention solves the problem that polymerization rate of current catalyst in lactic acid and glycolic acid is slow. The benzoic acid stannous is the catalyst used for preparing low-molecular polymer lactic acid with lactic acid dewatering; benzoic acid stannous is the catalyst used for preparing lactide with low-molecular polymer lactic acid cracking; benzoic acid stannous is the catalyst used for preparing polylactic acid with lactide polymerizing; benzoic acid stannous is the catalyst used for preparing low-molecular polymer glycolic acid with glycolic acid dewatering; benzoic acid stannous is the catalyst used for preparing glycolide with low-molecular polymer glycolic acid cracking; benzoic acid stannous is the catalyst used for preparing poly-glycollide with glycolide polymerizing. The benzoic acid stannous is the catalyst used for polymerizing glycolide, lactide and epsilon-caprolactone. Using the benzoic acid stannous is low content, high productivity, high product purity, low temperature and good repeatability.

The invention discloses a reduced slushing agent for building concrete, which is a high-efficiency polycarboxylate slushing agent. The reduced slushing agent for building concrete is prepared through adding maleic anhydride, diethylene glycol monobutyl ether, tertiary butanol and a catalyst into water firstly; then, heating the obtained mixture to 120 DEG C, carrying out heat preservation 4 hours, and cooling the obtained mixture to 80 DEG C; adding an initiator, a methacrylic acid and isoamyl alcohol polyoxyethylene ethers into the obtained mixture; continuing to carry out heat preservation 2 hours, and cooling the obtained solution to 35 DEG C; and neutralizing the obtained solution by using a neutralizing agent until the PH value of the obtained solution is 7-8. Through the way, the reduced slushing agent for building concrete disclosed by the invention can effectively improve the water reducing rate and dispersity of the slushing agent, and increase the strength of concrete, so that the concrete is excellent in slump retaining property, fluidity and crack resistance; and the slushing agent has a good compatibility with concrete.

The invention discloses a preparation method of silicon carbide ceramic precursor polycarbosilane. The method comprises the following steps: (1) adding sodium metal into a reaction solvent, heating upunder stirring and gradually adding halomethyltrialkoxysilane to continue the reaction so as to mainly produce sodium salt, alkoxy-containing polycarbosilane and sodium alkoxide; (2) removing the sodium salt produced in the step (1), adding a reducing agent after heating up, and reducing the alkoxy-containing polycarbosilane to produce a polycarbosilane product. Raw materials used in the preparation are simple in source and high in polymerization activity, and can introduce crosslinking groups through a plurality of different ways; and the obtained polycarbosilane has low viscosity and high purity, and can obtain silicon carbide ceramics with near-stoichiometric ratios after sintering.

Highly polymerizable diamine compounds having a phosphorylcholine group are disclosed. High-molecular weight polymers are obtained from the highly polymerizable diamine compound having a phosphorylcholine group as a monomer, and the polymers have improved mechanical strength, water resistance and heat resistance while maintaining excellent biocompatibility and processability of MPC polymers. Processes for producing the polymers are disclosed. The diamine compounds having a phosphorylcholine group are represented by Formula (I). The polymers contain at least 1 mol % of a specific structural unit with a phosphorylcholine group represented by Formula (II) and have a number average molecular weight of not less than 5,000. In the processes, the diamine compound is used as a monomer.

The invention provides a preparation method of polycarboxylate superplasticizer comprising amido groups, which synthesizes a target product by using two steps: first, polymerizing maleic anhydride and/or maleic anhydride esterification product with acrylamide to obtain modified acrylamide, subjecting the modified acrylamide to free radical copolymerization with unsaturated polyether and unsaturated carboxylic acid to finally synthesize the polycarboxylate superplasticizer comprising amide groups; when applied to concrete, the polycarboxylate superplasticizer comprising amido groups presents excellent retarding effect, presents higher initial dispersibility and time-dependent dispersibility of cement mortar than conventional polycarboxylate water reducers, and accordingly has a promising application prospect.

The present invention discloses an ethylene tetrapolymerization catalyst composition, which comprises a diphosphine ligand represented by a formula I, a transition metal compound, an aluminum-containing co-catalyst, water and an organic solvent, wherein R is selected from aryl or substituted aryl, and R' is respectively selected from alkyl, cycloalkyl, monocyclic aryl and polycyclic aryl. The invention further discloses a method for carrying out an ethylene tetrapolymerization reaction by using the catalyst composition. The formula I is defined in the specification.

The invention discloses a permeable closed amphoteric emulsion for a primer. The amphoteric emulsion is prepared from the following raw materials in parts by weight: 50 to 110 parts of deionized water; 10-60 parts of styrene, 5 to 20 parts of n-butyl acrylate; 5-20 parts of iso-octyl acrylate, 2-5 parts of an emulsifier, 2-5 parts of glycidyl methacrylate, 2-5 parts of dodecyl methacrylate, 2-5 parts of methyl erucate, 2-5 parts of a cationic monomer, 2-5 parts of an anionic monomer, 0.5-2.5 parts of a crosslinking monomer, 1-5 parts of a hydrophilic monomer and 0.5-2 parts of an initiator. The emulsion is zwitter-ionic amphoteric emulsion for permeable closed primer, and has excellent paint preparation stability, excellent permeation reinforcing performance and salt and alkali flooding resistance.

The invention relates to an improvement of a method for preparing dimer acid and dimer acid methyl ester by using unsaturated fatty acid and corresponding fatty acid methyl ester thereof, which is characterized in that a catalyst for reaction is sulfonate ionic liquid which contains SO3H functional groups and accounts for not less than 0.5% in parts by weight, the reaction is carried out at the temperature of 150-300 DEG C, the iodine value of products are controlled to be 65-80%, and the products and the catalyst are stratified by standing after the reaction is complete. The method has the advantages of high polymerization reaction activity, fast reaction speed and relatively mild reaction conditions, and the reaction can be carried out at atmospheric pressure and relatively low temperature, thereby not only reducing the reaction energy consumption and having low requirements on equipment, but also greatly reducing the preparation cost. The catalyst has good stability and small usingquantity, only 0.5% by weight of the catalyst can carry out full reaction, the catalyst is difficult to hydrolyze and easy to realize the phase separation with the products, the catalyst can be separated from the products only through ordinary standing or centrifugation without entrainment of the products, the catalyst can be repeatedly recycled, and the production process is environment-friendly.

The present invention discloses an ethylene tetrapolymerization catalyst composition, which comprises a diphosphine ligand represented by a formula I, a transition metal compound, an aluminum-containing co-catalyst, water and an organic solvent, wherein R1 and R2 are respectively and independently selected from alkyl, cycloalkyl and aryl, and R3, R4, R5 and R6 are respectively and independently selected from aryl and cycloalkyl. The invention further discloses a method for carrying out ethylene tetrapolymerization by using the catalyst composition. The formula I is defined in the specification.

The invention relates to an ethylene oligomerization catalyst composition which comprises a chloride 2-benzoxazolyl-6-acetyl condensed amino ferrite (II) complex shown in formula I, an aluminum-containing promoter and tert-butyl hydroperoxide. The invention further provides an ethylene oligomerization method. The ethylene oligomerization catalyst composition provided by the invention is applied to ethylene oligomerization, and is high in reaction activity at low temperature in the presence of low Al/Fe, that is, the reaction activity is up to 1.62*10<7>g.mol (Fe)<1>.h<1>.

The invention discloses an efficient preparation method and application of poly beta farnesene with ultra-high molecular weight. The invention belongs to the field of polymer synthesis. The inventionaims to solve the technical problems of low molecular weight of poly beta farnesene obtained by existing methods and higher cost of adopted rare earth metal reactants. The method comprises the following steps: adding a solvent, a main catalyst, a cocatalyst and a beta-farnesene monomer into a reactor according to any sequence under the protection of inert gas, performing polymerizing for 10-240 minutes at 0-100 DEG C while stirring, adding a quenching agent and an anti-aging agent into the reaction system for quenching reaction, repeatedly performing washing with ethanol, and carrying out vacuum drying to obtain the poly beta-farnesene . The main catalyst is a bipyridine iron complex. The microstructure of the obtained poly beta-farnesene is composed of 3,4-poly beta-farnesene with the molar fraction of 50%-70% and 1,4-poly beta-farnesene with the molar fraction of 30%-50%, the number-average molecular weight of the obtained poly beta-farnesene ranges from 8.0 x 10<5> g/mol to 1.7 x 10<6> g/mol, and the molecular weight distribution ranges from 1.5 to 3.5.

The present disclosure provides a novel transition metal compound having excellent structural stability together with polymerization reactivity, and thereby is useful as a catalyst in preparing an olefin-based polymer, particularly, a low density olefin-based polymer, and a catalyst composition including the same.