80 results about "Star-shaped polymer" patented technology

A star-shaped polymer having an alkoxy silane end group and containing an ether group at the center thereof, which is represented by formula (I), is useful as a pore introducer to obtain a low dielectric silicate polymer film having nano-pores distributed regularly and evenly. The star-shaped polymer is prepared by comprising conducting a ring open polymerization of a cyclic monomer and a polyhydric alcohol, and reacting the resulting polymer with an alkoxy silane compound.

The invention belongs to the technical field of biomedical polymer materials, and discloses beta-cyclodextrin based 21-arm star-shaped polymers as well as a preparation method thereof and a monomolecular micelle / gold nanoparticle hybrid material system based on the beta-cyclodextrin based 21-arm star-shaped polymers and an imaging application. The polymers have a structure represented by a following formula (1) in the description, wherein x is one selected from 4 to 20, y is one selected from 4 to 15, and z is one selected from 5 to 25. According to the invention, the ratio of each block of the polymers is easily regulated and controlled, so that monomolecular micelles with stable structures and small particle sizes can be prepared. The invention also provides gold nanoparticles with the small particle sizes and good stability prepared by an in-situ method based on the above polymer monomolecular micelle system, and the in-vitro CT imaging is realized, and the valuable preparation technology is provided for the future integrated treatment system.

The invention belongs to the fields of intelligent bionic materials, high-molecular materials and biomedical engineering, and concretely relates to a polydopamine particles-doped star-shaped polymer of a multi-responsive self-healing hydrogel, and the self-healing hydrogel and a preparation method thereof. In the present invention, the polydopamine nanoparticles and the star-shaped polymer SPDMAEMA-AA are prepared first; and the polydopamine nanoparticles, SPDMAEMA-AA and branched polyethyleneimine are mixed in proportion to form a crosslinked network by forming a dynamic reversible enamine bond through the acetoacetate on SPDMAEMA-AA and an amino group in the PEI molecules to obtain the hydrogel. The self-healing hydrogel material prepared by the invention has good near-infrared responsiveness, biocompatibility and high self-healing efficiency, and has potential applications in the fields of solid-state band-aids, drug slow release, cell culture, and a double-layer drive.

The invention relates to technical field of degradation catalysis of pollute substance of waste water, in particular to a thermosensitivity recyclable metalloporphyrin visible light degradation catalyst and a preparation method thereof. An existing metalloporphyrin visible light degradation catalyst is bad in water-solubility and difficult to recycle. According to the thermosensitivity recyclable metalloporphyrin visible light degradation catalyst and the preparation method thereof, the light degradation catalyst is a star-shaped polymer, wherein divalent metal ions of the light degradation catalyst is Zn divalent metal ion, Co divalent metal ion or Fe divalent metal ion, and the molecular weight of the light degradation catalyst is ranged from 2000 to 15000. The preparation method of the thermosensitivity recyclable metalloporphyrin visible light degradation catalyst is an atom transfer radical polymerization method which comprises the following steps of: firstly, reaction between 5, 10, 15, and 20-4-hydroxyphenylacetic acid phenyl group porphyrin and metal acetate and generation of porphyrin metal complex, then, halogenating reaction between the porphyrin metal complex and halide and obtaining of atom transfer radical polymerization initiator, and thirdly atom transfer radical polymerization of N-isopropyl acryamide monomer initiated by the initiator and obtaining of an end product, namely the thermosensitivity recyclable metalloporphyrin visible light degradation catalyst. The prepared catalyst is good in water-solubility, capable of adapting to aqueous medium waste water degradation system, and capable of being recycled completely, simply and without being damaged.

The invention discloses a structure-controllable water soluble star-shaped polymer with beta-cyclodextrin being a core. A preparation method includes: S1) performing a reversible addition-fragmentation chain transfer polymerization reaction to synthesize the structure-controllable water soluble star-shaped polymer which is narrow in molecular weight distribution, and performing sulfhydryl conversion to the chain terminal; S2) modifying a beta-cyclodextrin core to introduce a C=C bond; S3) performing a sulfhydryl-alkene click chemical reaction to graft the chain polymer onto the modified beta-cyclodextrin core to form the structure-controllable water soluble star-shaped polymer with beta-cyclodextrin being a core. In the method, the reaction monomer is acrylates or acrylamides, and the chain transfer agent is dithio ester or trithio ester. The polymer is prepared in a manner of "firstly arm and secondly core", wherein all the polymer arms have been accurately represented before "core connection", so that the polymer has controllable and definite structure and the uniformity of the polymer arms is guaranteed; in addition, by regulation of the arm-core ratio of the polymer, the numberof the arms is controllable.

Provided is a metal nanoparticle composite that has excellent stability over time and shelf life and is useful as a starting material for a metal nanoparticle dispersed film. Also provided is a method for producing the same, a metal nanoparticle dispersion, a composition for forming a metal nanoparticle dispersed film, and a metal nanoparticle dispersed film. The metal nanoparticles are obtained by supporting metal nanoparticles (B) in a star-shaped polymer (A) having a central nucleus and arms joined to the central nucleus, wherein the arms comprise repeating units represented by the following general formula (1) and repeating units represented by the following general formula (2). (In formula (1), R1 is a hydrogen atom or C1-4 alkyl group and in formula (2), R2 is a methyl or ethyl group and k is an integer between 1 and 10.)

Intercalates and exfoliates formed from layered materials and dendritic polymers are disclosed, together with the uses of these materials, e.g. in producing composite materials. The dispersion of layered materials in a dendritic polymer matrix (hyperbranched polymers, star shaped polymers or star branched polymers) or has not been disclosed in the prior art. The high number of end-groups per molecule of dendritic polymer combined with their unique globular architectures leads to large intergallery spacings when intercalated in layered silicates and particularly facile exfoliation in spite of the high molar mass of the dendritic polymer. The excellent processability and potential high reactivity of dendritic polymers makes them extremely promising for thermoset applications, and coatings.

The invention discloses a novel quick separation method of bacilluscereus, which provides the basis for the subsequent research for a target bacterium and relates to the technical field of biology. The novel quick separation method comprises the steps of: carrying out covalent coupling on a multi-arm star-shaped polymer and an antibody, coating the antibody-modified multi-arc star-shaped polymer on a long-chain biotin molecule, capturing the target bacterium in a sample solution by the antibody and long-chain biotin co-modified multi-arc star-shaped polymer, recognizing and coupling the long-chain biotin multi-arm star-shaped polymer in the sample solution by a streptavidin-modified nano magnetic bead, separating and heavily-suspending the captured bacterium; a heavily-suspended liquid can be directly analyzed in subsequent. Compared with a conventional bacterium magnetic separation method, the novel quick separation method is more suitable for carrying out magnetic separation on the bacterium in a complex matrix; the separation efficiency of the target bacterium in a sample is increased.

The invention provides a method for preparing a submicron pore diameter polymer porous membrane, and belongs to the technical field of chemical engineering and materials. At first, through the mutual static electricity effect, cation chain transfer agents containing trithiocarbonate groups are modified onto the surface of multi-metal oxygen clusters to obtain a compound of the cation chain transfer agents and the multi-metal oxygen clusters; further, through a reversible addition-fracture chain transfer polymerization reaction, polystyrene is grafted onto the outer peripheries of the compounds to obtain star-shaped polymers using the multi-metal oxygen clusters as the cores and the polymer as the arms; finally, the star-shaped polymers are used as precursors, and the polymer porous membrane is prepared by a water dripping template method. On the other hand, as a water drip stabilizing agent, the water drips can maintain the small dimension, so that the submicron pore diameter polymer porous membrane can be formed. The polymer porous membrane prepared by the method has application prospects in the fields of separation and soft templates.

As an engine oil composition having exceptional fuel-efficient performance, there is provided an engine oil composition characterized by containing, in a lubricant base oil having a saturated component of 70 mass% or above and a viscosity index of 90 or above, at least 4 mass%, based on the total amount of the engine oil composition, of a star-shaped polymer as a viscosity index improver, the ratio (B / A) of high-temperature, high-shear viscosity (B) at 1 × 107 / s shear velocity and 100ºC to high-temperature, high-shear viscosity (A) at 1 × 106 / s shear velocity and 100ºC being 0.85 or less.

The invention discloses injectable hydrogels which are in the form of crosslinked nano beads or particle in the size range 5 nm to 10 μm, comprising PAMAM dendrimer with asymmetrical peripheral end groups such that one of the terminal groups is involved in formation of hydrogel and the other in involved in the conjugation of drugs or imaging agents and their methods of preparation. The said gel is formed by reaction of the PAMAM dendrimer with asymmetrical end groups with other polymer wherein the other polymer is selected from the group of linear, branched, hyperbranched or star shaped polymers with functionalized terminal groups. The PAMAM dendrimer with asymmetrical terminal groups consists of a Generation 2 and above PAMAM dendrimer with symmetrical end groups modified using the amino acids or their modified forms. The gel disclosed in the present invention is formed as small crosslinked particles in the size range 25 nm to 10 μm and is suitable for injectable delivery of hydrogel to any of the body orifices, tissues by intramuscular or subcutaneous route and ocular delivery for the purpose of therapeutic treatment and imaging.