The present invention relates to a process of a process for preparation of a polymer dispersion comprising a step (E) of free radical polymerization in an aqueous medium (M) in the presence of: at least a pre-polymer (pO) soluble in the medium (M), at least one free-radical polymerization initiator, and at least one ethylenically unsaturated hydrophobic monomer (m) which is chosen from an alkyl (meth)acrylate of at least C6, wherein the aqueous medium (M) includes water and at least one water miscible solvent.

The present invention relates to the field of water-soluble or water-dispersible copolymers comprising at least one random copolymer comprising styrene, methacrylic acid, acrylic acid and butyl acrylate.

The invention provides UV-sensitive monomers, comprising a cyclopropenone-containing group, which acts as a masked dibenzocyclooctyne (DBCO)/dibenzoazocyclooctyne (DIBAC) group. The monomers of the invention can be polymerized for example via reversible addition fragmentation chain transfer (RAFT) polymerization techniques to yield a polymer comprising the masked DBCO/DIBAC group. In certain embodiments, the DBCO/DIBAC group can be unmasked under controlled conditions, allowing conjugation of small molecules and/or macromolecules to the polymer through highly selective and efficient strain-promoted azide alkyne click chemistry (SPAAC).

An ultraviolet-ray absorbing polymer containing a monomer unit represented by general formula (12) below and a monomer unit derived from a monomer represented by general formula (1) below. In general formula (12), R.sub.6 represents any one selected from a group consisting of a hydrogen atom and a methyl group, U represents a hydrocarbon group, and the hydrocarbon group includes a skeleton absorbing ultraviolet rays and optionally contains a heteroatom. In general formula (1), R.sup.16 represents any one selected from a group consisting of a hydrogen atom and a methyl group, and Z represents any one selected from a group consisting of a chain hydrocarbon group having 10 or more carbon atoms and a polycyclic hydrocarbon group having 10 or more carbon atoms.

##STR00001##

The present invention relates to a method for preparing graphene using a novel block copolymer. The present invention has features that, by using the block copolymer to mediate graphene that is hydrophobic and a solvent of a feed solution that is hydrophilic, the exfoliation efficiency of graphene as well as the dispersion stability thereof can be increased during high-pressure homogenization.

A neutral layer composition, which is capable of forming a neutral layer that can effectively control orientation characteristics of various block copolymers is provided.

A preparation method of an ionic liquid shale inhibitor for drilling fluid comprises the following step: subjecting the imidazole-based ionic liquid to a polymerization reaction in water environment under an inert atmosphere, and the produced polymer is used as an ionic liquid shale inhibitor for drilling fluid. The ionic liquid shale inhibitor for drilling fluid has the advantages of desirable inhibition effect, good compatibility, strong high-temperature resistance, simple preparation method and low cost.

The invention relates to the technical field of oil and gas drilling, and discloses an amphiphilic block polymer ultralow-permeability agent and an intelligent temporary plugging type water-based drilling fluid. The ultralow-permeability agent contains a structural unit provided by styryl hydrophobic monomer, maleic anhydride and acrylamide; the drilling fluid contains two or more of water, sodium bentonite, Pac-Lv, the ultralow-permeability agent, calcium carbonate, one-way plugging agent, white asphalt and barite which are stored in a mixed manner or independently stored. When the amphiphilic block polymer provided by the invention is used as the ultralow-permeability agent of the intelligent temporary plugging type water-based drilling fluid, the self-adaptive characteristic is realized; according to the amphiphilic block polymer, temporary plugging layer gaps formed in pore and throats by plugging materials in drilling fluid can be fully filled under the condition that the sizes and the distribution of the pore and throats of reservoirs are not required to be clear, so that the permeability of temporary plugging layer is greatly reduced, ultralow-permeability is realized, and the amphiphilic block polymer is weak in tackifying effect, has gel-improving effect and can improve the rheological property of the drilling fluid.

By using a graft polymer comprising a dendritic polymer with a styrene skeleton and a hydrophilic polymer grafted to a terminal thereof, a temperature-responsive substrate for cell culture having a temperature-responsive surface for cell culture that allows cells to be cultured with high efficiency and which yet allows cultured cells to be exfoliated in a short period of time and with high efficiency by simply changing the temperature of the substrate surface can be prepared conveniently. If this temperature-responsive substrate for cell culture is used, cells obtained from a variety of tissues can be cultured with high efficiency. If this culture method is utilized, cultured cells can be exfoliated intact in a short amount of time with high efficiency. In addition, by using this graft polymer, a wide range of peptides and proteins can also be separated by simply changing the temperature of a chromatographic carrier. This allows for convenient separation procedure and improves the efficiency of separating operations. What is more, the stereoregularity of the dendritic polymer per se may be utilized to enable separation of solutes based on differences in their molecular structures.

Disclosed is a graft copolymer containing a polyfluorene-based polymer as a main chain and a polyvinylidene fluoride (PVDF) as a side chain, and an element including the same. The graft copolymer contains both the polyfluorene-based polymer and the PVDF, so that the graft copolymer may increase miscibility between polymers to prepare a composite having excellent performance, prepare an uniform thin film through a solution process, and be used as a single material that exhibits both piezoelectric properties and luminescence properties.