Aspects of the present invention relate to polymers, and particularly to farnesene polymers functionalized with one or more oxirane groups and, optionally, one or more hydroxyl groups. According to one aspect of the invention, provided is an epoxidized and optionally hydroxyl-functionalized polyfarnesene. The epoxidized farnesene polymer has at least one of a side chain or a main backbone functionalized with at least one oxirane group and, optionally, at least one terminal end functionalized with a hydroxyl group. In accordance with another aspect of the invention, a method is provided for preparing an epoxidized and optionally hydroxyl-functionalized polyfarnesene. The method includes epoxidizing a farnesene polymer, which may optionally contain one or more terminal hydroxyl groups, to functionalize at least one of a side chain or a main backbone of the farnesene polymer with an oxirane group.

The present invention relates to the technical field of well drilling, and discloses a plugging agent for temperature-resistant calcium-resistant water-based drilling fluid used in oil and gas reservoir protection, a drilling fluid, and uses of the plugging agent and the drilling fluid. The plugging agent for temperature-resistant calcium-resistant water-based drilling fluid used in oil and gas reservoir protection contains acrylamide-diallyldimethylammonium chloride copolymer modified graphene, wherein in the acrylamide-diallyldimethylammonium chloride copolymer, a molar ratio of structural units provided by acrylamide to structural units provided by diallyldimethylammonium chloride is 1:5-15, and the number-average molecular weight of the acrylamide-diallyldimethylammonium chloride copolymer is 15,000-30,000. The water-based drilling fluid described in the present invention is especially applicable to well drilling in deep salt-gypsum formations, and can exhibit good filtrate reducing, plugging, temperature-resistant, anti-collapsing, and reservoir protection performance.

The present invention relates to a modifier represented by Formula 1, a modified conjugated diene-based polymer having a high modification ratio which includes a modifier-derived functional group, and a method of preparing the polymer.

Disclosed is a resin including a structural unit represented by formula (I) and a structural unit represented by formula (a2-A), and a resist composition:

##STR00001##

wherein R.sup.1 represents a hydrogen atom or a methyl group; L.sup.1 and L.sup.2 each represent O or S; s1 represents an integer of 1 to 3; s2 represents an integer of 0 to 3; R.sup.a50 represents a hydrogen atom, a halogen atom, or an alkyl group which may have a halogen atom; R.sup.a51 represents a halogen atom, a hydroxy group, an alkyl group, an alkoxy group, an alkylcarbonyl group or the like; A.sup.a50 represents a single bond or *X.sup.a51-(A.sup.a52-X.sup.a52).sub.nb; A.sup.a52 represents an alkanediyl group; X.sup.a51 and X.sup.a52 each represent O, COO or OCO; nb represents 0 or 1; and mb represents an integer of 0 to 4.

The present disclosure is directed to multiphase dispersions and nanocomposites comprised of a continuous matrix or binder and an endohedrally impregnated cellular carbon filler. These nanocomposites may exhibit superior mechanical, electrical, thermal, or other properties, and may be used in a variety of products, including hierarchical fiber-reinforced composites with nanocomposite matrices.

The present invention provides a vinyl alcohol-vinyl acetate copolymer having excellent solubility and a method for producing a vinyl alcohol-vinyl acetate copolymer. Provided is a vinyl alcohol-vinyl acetate copolymer including a unit of vinyl alcohol and a unit of vinyl acetate, the vinyl alcohol-vinyl acetate copolymer having a randomness value R of 0.5 or higher, the randomness value R being obtained using the following equation (1): $\begin{array}{cc}R=\frac{1}{L_A}+\frac{1}{L_O}& \left(1\right)\end{array}$
where L.sub.O represents a mean chain length of the unit of vinyl alcohol and L.sub.A represents a mean chain length of the unit of vinyl acetate.

The present disclosure provides a process. The process includes (i) forming a composition containing a peroxide-modified ethylene-based polymer selected from the group consisting of a peroxide-modified ethylene/a-olefin multi-block copolymer, a peroxide-modified low density polyethylene, and combinations thereof; (ii) contacting the composition with a blowing agent to form a foam composition; and (iii) forming foam beads comprising the foam composition. The present disclosure also provides a foam bead produced by said process.

Provided is a resin film for an electronic device including: a resin containing a polymer; hygroscopic particles dispersed in the resin and having a primary particle diameter of 200 nm or less; and a dispersant, wherein an absolute value of a difference in refractive index between the resin and the particles is 0.05 or less. The resin is preferably a thermoplastic resin, and more preferably a thermoplastic elastomer. The polymer is preferably one or more types selected from an aromatic vinyl compound-conjugated diene copolymer and a hydrogenated aromatic vinyl compound-conjugated diene copolymer. An electronic device including the resin film for an electronic device is also provided.

The polyvinyl alcohol according to the present invention to be used as a dispersant for suspension polymerization for polyvinyl chloride has a degree of saponification of 60 to 80 mol %, a block character of 0.4 to 0.6, an integration value defined by the following (a) of 0.04 to 0.1 and an integration value defined by the following (b) of 0.01 to 0.2 in a .sup.1H-NMR spectrum, and a 0.1% by mass aqueous solution of the polyvinyl alcohol has a UV absorbance at a wavelength of 320 nm of 0.18 or more and less than 0.3. (a) An integration value from 5.42 to 5.62 ppm of a peak or peaks observed at 5.50 to 5.54 ppm when an integration value from 3.65 to 4.05 ppm of a peak or peaks observed at 3.83 to 3.87 ppm is assumed to be 100. (b) An integration value from 5.76 to 5.98 ppm of a peak or peaks observed at 5.86 to 5.90 ppm when an integration value from 3.65 to 4.05 ppm of a peak or peaks observed at 3.83 to 3.87 ppm is assumed to be 100.

The present invention relates to the technical field of well drilling, and discloses a temperature-resistant calcium-resistant water-based drilling fluid for oil and gas reservoir protection and a use thereof. The water-based drilling fluid contains a filtrate reducer and a plugging agent, wherein the filtrate reducer is a copolymer that contains structural units represented by formula (1), structural units represented by formula (2), and structural units represented by formula (3), wherein, the mass ratio of the structural units represented by formula (1) to the structural units represented by formula (2) to the structural units represented by formula (3) is (0.1-0.2):1:(0.05-0.1), and the number-average molecular weight of the copolymer is 10,000-100,000, the plugging agent is acrylamide-diallyldimethylammonium chloride copolymer modified graphene. The water-based drilling fluid described in the present invention can exhibit excellent filtrate reducing, plugging, temperature-resistant, anti-collapsing, and reservoir protective performance when it is applied in well drilling in deep high-temperature wells.

##STR00001##