Abstract: The present invention relates to a method for preparing homo- and co-polymers having high molecular weights in high yields by polymerizing cyclic olefin compounds using a complex prepared by mixing a nickel salt compound, an organoaluminoxane compound, and at least one fluorine-containing compound.

Abstract: The present invention relates to a method for preparing homo- and co-polymers having high molecular weights in high yields by polymerizing cyclic olefin compounds using a complex prepared by mixing a nickel salt compound, an organoaluminoxane compound, and at least one organic boron compound.

Abstract: This invention relates to a process for selectively hydrogenating the unsaturated double bonds of conjugated diene units of a homopolymer or copolymer. By using a highly active novel homogeneous organo titanium catalyst represented by formula (I) and lithium hydride (LiH) prepared in solution of organo lithium compound and hydrogen as a reducing agent, a polymer could be hydrogenated with significantly high yield and good reproducibility. In addition, this invention is characterized by a novel method in that when a copolymer containing a conjugated diene and vinyl-substituted aromatic hydrocarbon, the unsatured double bonds of conjugated diene units are selectively hydrogenated.

Abstract: A radial multi-block copolymer contains a tapered block as represented by the following formula 1. The radial multi-block copolymer, which includes a polystyrene block, a poly(isoprene-styrene)tapered block, a polyisoprene block, and a polybutadiene block, can be used as an excellent pressure-sensitive adhesive material. (pA-pT-pB)m-X-n(pC-pB-pT-pA)??Formula 1: where pA is the polyvinyl aromatic block; pT is the poly(isoprene-styrene)tapered block; pB is the polyisoprene block; pC is the polybutadiene block; X is the residue of a multi-functional coupling agent used in preparation of the radial multi-block copolymer; m and n are integers equal to or greater than 1, representing the number of branches associated with X; and pT=pTA+pTB, where pTA is the pA component of pT, and pTB is the pB component of pT.

Abstract: The present invention provides a method for preparing a copolymer useful for the manufacture of tires by coupling the ends of a living polymer obtained from copolymerization of a diene monomer and a vinyl aromatic monomer in the presence of an organolithium catalyst and a hydrocarbon solvent with a multi-reactive polysiloxane compound and then modifying the remaining uncoupled ends of the polymer with an amine compound. The use of the copolymer thus obtained for the fabrication of tires improves the affinity to silica as well as carbon black used as a reinforcing material and provides enhanced properties required for tires, such as increased wet traction, reduced rolling resistance, and increased tread wear.

Abstract: The present invention provides a method for preparing a copolymer useful for the manufacture of tires by coupling the ends of a living polymer, obtained from copolymerization of a diene monomers in the presence of an organolithium initiator and a hydrocarbon solvent, with a multi-reactive polysiloxane compound, and then completing the reaction or subsequently modifying the remaining uncoupled ends of the polymer with an amine compound. The use of the copolymer thus obtained for tire production improves the affinity to silica and greatly enhances the dynamic properties required for tires, such as wet traction and rolling resistance.

Abstract: The present invention relates to a method for evaluating the crosslink degree of a vulcanized sample in real time during a vulcanization process or diagnosing the electrical properties of the sample after the completion of the vulcanization process, and then determining an optimal vulcanization time and an optimal content of each constituent gradient of a composition for vulcanization that optimize the properties of the composition according to the vulcanization conditions, for the sake of improving the properties of the vulcanized sample prepared from a polymer by vulcanization at a high temperature.

Abstract: The present invention provides a chemically amplified resist composition including a novel polymer, a photoacid generator, and a solvent: The chemically amplified resist can form a resist pattern that is excellent in adhesiveness with a low dependency to the substrate, transparency at the far ultraviolet wavelength range such as KrF Excimer laser or ArF Excimer laser, dry etch resistance, sensitivity, resolution, and developability. In addition, the polymer contains a maximum number of saturated aliphatic rings to enhance etching resistance, and additionally includes an alkoxyalkyl acrylate monomer introduced as a solution to the problem with the conventional polyacrylate resist in regard to edge roughness of the pattern, to form a uniform edge of the pattern because the alkylalcohol compound generated together with a formaldehyde and a carboxylate compound by a deprotection reaction of the alkoxyalkyl acrylate monomer with an acid acts as a solvent or an antifoaming agent in the pattern.

Abstract: The present invention includes modified phytochrome A (PHYA) nucleic acid molecules in which DNA sequences coding for “active site” amino acid residues have been mutated to generate hyperactive phytochromes. In particular; a serine/threonine residue at the hinge between the N- and C-terminal domains as well as at the N-terminal serine/threonine cluster of phytochromes (e.g., serine-598 and serine-7 in oat phytochrome A) for (a) Pr/Pfr-dependent phosphorylation and (b) dephosphorylation by a phytochrome phosphatase (PP2A) was substituted with alanine. (c) In addition, amino acid residues within the phytochrome chromophore pocket are mutated to generate the bathchromic shift of the Pr-absorption band of both wild type and above-mentioned mutant phytochromes.

Abstract: Disclosed is a hetero-branched radial block copolymer suitable as a base polymer of pressure-sensitive adhesives, the hetero-branched radial block having a hetero-branched structure comprised of polystyrene, polyisoprene, and polybutadiene blocks and being represented by (pS-pI)3X-(pB-pI-pS) wherein pS is polystyrene; pI is polyisoprene; pB is polybutadiene; and X is a residue of a tetravalent coupling agent.

Abstract: The present invention relates to the unbalanced multi-block styrene-butadiene-styrene (SBS) and provides the copolymer represented by the following structure, mB1*S1-lB2-S2-sB3, wherein B is a butadiene block, S is a styrene block, l, m, s are the relative size among the blocks (i.e., large size, middle size, and small size, respectively), and * is the tapered block between mB1 block and S1 block (i.e., random copolymer of a kind). They have to satisfy the following related expressions. 0.01lB2?mB1?0.5lB2 and 0.01mB1?sB3?0.5mB1 ??a) 0.5S1?S2?1.5S1 ??b) 5%?*%?25% ??c) In the related expression, the value of B1 and S1 include tapered block for the sake of convenience, and * % is the random styrene content in all the styrene in SBS. The unbalanced multi-block SBS of this invention exhibits excellent processability in the preparation of hot-melt adhesives, reducing processing hours.

Abstract: The present invention relates to the compounds generating strong acids (described hereafter as “acid generators”) decomposed by heat and the composition of thin film containing the same. Provided are the compounds represented by the structure of formula I and the composition containing the compounds. wherein X is alkyl or aryl group and R is hydrogen atom, hydroxy, alkoxy or alkyl group. The abovementioned acid generators of the present invention generate acid by heat at relatively low temperatures, preventing the change in the ratio of the composition due to evaporation of some components in the composition. Accordingly, it has the advantageous effect that the ratio of components in the composition is controlled and the preparation of the thin film with the wanted properties is simplified.

Abstract: Disclosed is a synthesis method of cyclohexyl phenyl ketone with a high selectivity and a high yield from 1,3-butadiene and acrylic acid in the presence or absence of benzene or a non-aromatic organic solvent in the same reaction without a step of separating or purifying intermediates, the synthesis method including sequentially carrying out a [2+4] Diels-Alder reaction, a hydrogenation reaction, a chlorination reaction and a Friedel-Crafts reaction in the presence/absence of benzene or a non-aromatic organic solvent without separation of intermediates.

Abstract: The present invention relates to a bimodal linear block copolymer containing a tapered block and its manufacturing method. The bimodal linear block copolymer includes a hexa-block copolymer of vinyl aromatic block(PS1)-conjugated diene block(PB1)-tapered block(T1)-vinyl aromatic block(PS2-PS3)-conjugated diene block(PB2)-vinyl aromatic block (PS4) as prepared by adding two charges of an initiator, and a tri-block copolymer of vinyl aromatic block(PS3)-conjugated diene block(PB2)-vinyl aromatic block (PS4). The bimodal linear block copolymer is prepared by adding more than one charge of the initiator, vinyl aromatic monomers and conjugated diene monomers to acquire transparency, toughness, rigidity and flexibility, and thereby can be used for sheets or films, or injection or blow molding products.

Abstract: The present invention relates to a process for polymer hydrogenation that includes: polymerizing or copolymerizing at least one conjugated diene in a hydrocarbon solvent using an organic alkali metal polymerization initiator to generate a living polymer; adding a terminating agent selected from amines, esters, ketones, or halogen compounds to deactivate the active terminal of the living polymer; and selectively hydrogenating the conjugated diene polymer using at least one organotitanium compound and a lithium hydride, which is prepared from a reactor equipped with a high-speed injection nozzle and thereby precisely controlled in regard to particle diameter.

Abstract: The present invention relates to a bimodal linear block copolymer containing a tapered block and its manufacturing method. The bimodal linear block copolymer includes a hepta-block copolymer of vinyl aromatic block(PS1)-conjugated diene block(PB1)-tapered block(T1)-vinyl aromatic block(PS2-PS3)-conjugated diene block(PB2)-tapered block(T2)-vinyl aromatic block (PS4), and a tetra-block copolymer of vinyl aromatic block(PS3)-conjugated diene block(PB2)-tapered block(T2)-vinyl aromatic block (PS4) as prepared by adding two charges of an initiator. The bimodal linear block copolymer is prepared by adding several charges of the initiator, vinyl aromatic monomers and conjugated diene monomers to acquire transparency, toughness, rigidity and flexibility, and thereby can be used for sheets or films, or injection or blow molding products.

Abstract: The present invention relates to an end-modified diene copolymer and a rubber composition for tire tread containing the same. More particularly, the present invention relates to a polymer and a rubber composition for tire tread comprising a mixture of the polymer with a vulcanizing agent and an inorganic filler such as carbon black and silica, the polymer being prepared by reacting the active end of a conjugate diene polymer, or a copolymer comprising at least one conjugate diene compound and a vinyl-substituted aromatic compound, polymerization-initiated using an organic lithium catalyst, with a coupling agent. The rubber composition for tire treads comprising the end-modified diene copolymer as an ingredient rubber enhances rolling resistance and wet skid resistance as well as mechanical properties directly concerned to the properties of the tires.

Abstract: The present invention relates to a method for preparing a copolymer containing a combined linear and nonlinear block, that is, mikto block, a copolymer prepared from the method, and usages of the copolymer. More particularly, the present invention provides a novel method for preparing a multi-component copolymer by polymerization using a multifunctional compound and one charge of an initiator, and a copolymer having a mikto block including different types of terminal blocks.

Abstract: Disclosed is a novel high 1,4-cis polybutadiene-polyurethane copolymer and a preparation method thereof. The present invention provides a high 1,4-cis polybutadiene-polyurethane copolymer represented by the following formula 1 and having an average molecular weight of at least 100,000, and a method for preparing the high 1,4-cis polybutadiene-polyurethane copolymer that includes polymerizing 1,3-butadiene or butadiene derivatives with a catalyst comprising a rare earth compound, a halogen-containing compound and an organoaluminum compound in the presence of a non-polar solvent, to prepare a polybutadiene having a high 1,4-cis content of at least 95%; and then introducing a polyurethane group to the polybutadiene.

Abstract: The present invention related to two cDNA clones, designated to PepDef (pepper defensin protein gene) and PepThi (pepper thionin-like protein gene) and individual component; thereof including its coding region and its gene product; modification thereto; application of said gene, coding region and modification thereto; DNA construct, vectors and transformed plants each comprising the gene or part thereof.