An 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.

A method for producing a fluoropolymer by solution polymerization or dispersion polymerization, the method including: in the presence of an initiator, a chain transfer agent, and a solvent, (i) homopolymerizing tetrafluoroethylene; or (ii) randomly copolymerizing tetrafluoroethylene and at least one of a monomer represented by the following formula (1) or a monomer represented by the following formula (2). The chain transfer agent includes at least one selected from dithioester compounds, dithiocarbamate compounds, trithiocarbonate compounds and xanthate compounds. The fluoropolymer contains 50 to 100 mol % of a polymerized unit based on the tetrafluoroethylene. The formula (1): CF.sub.2═CR.sup.1R.sup.2 wherein R.sup.1 and R.sup.2 are as defined herein, the formula (2): CH.sub.2═CR.sup.3R.sup.4 wherein R.sup.3 and R.sup.4 are as defined herein.

This invention relates to poly(acrylonitrile) homo- or co-polymer having a number average molecular weight (M.sub.n) of at least 200,000 g/mol and a dispersity () of less than 1.3.

[Problem] To provide a method for efficiently producing a poly(ethylene glycol)-b-poly(halomethylstyrene), a novel poly(ethylene glycol)-b-poly(halomethylstyrene) produced using the method, and a derivative thereof.

[Solution] The target novel copolymer can be provided by introducing a functional group, which enables reversible addition-fragmentation chain transfer (RAFT) polymerization, to the ω terminal of poly(ethylene glycol) and copolymerizing the resulting poly(ethylene glycol) with a halomethylstyrene.

The present application relates to a block copolymer and uses thereof. The present application can provide a block copolymer—which exhibits an excellent self-assembling property and thus can be used effectively in a variety of applications—and uses thereof.

The disclosure provides biodegradable amphiphilic liquid crystalline copolymers that can readily self-assemble to nanoparticles in aqueous solutions and also allow for encapsulation of hydrophobic pharmaceutically active molecules.

The invention relates to polyfunctional polymers suitable in particular for the treatment of metal surfaces (metal finishing) and comprising: monomer units u1 bearing phosphonic acid functions; monomer units u2 bearing amine functions; and optionally monomer units u3 bearing alcohol units —OH.

The present invention is to provide a cell culture substrate including a block polymer including a segment having a lower critical solution temperature and a hydrophobic segment, in which the segment having a lower critical solution temperature has a degree of polymerization of 400 to 10,000. Also provided is a cell culture substrate, in which the hydrophobic segment is obtainable by polymerizing a monomer having a particular structure. Also provided is a cell culture substrate being laminated on a supporting medium. Furthermore, a cell culture substrate having an average film thickness of 1,000 nm or less is provided.

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.

An electrophoresis dispersion liquid according to the aspect of the invention contains at least one type of electrophoretic particles and a dispersion medium and, in the electrophoresis dispersion liquid, the content of the electrophoretic particles is 10 weight % or more to 30 weight % or less. Furthermore, the electrophoretic particles have base particles and a polymer (particle surface treatment agent) linked with the base particles and, in the electrophoretic particles, the content of the polymer is 5 weight % or more to 15 weight % or less.