Abstract: A method for manufacturing a trench field-effect transistor includes forming an epitaxial layer on a substrate; forming a trench in the epitaxial layer, forming a first insulating layer and a shielding conductor in the trench, where the first insulating layer surrounds the shielding conductor and partially fills the trench; forming a dielectric layer on the epitaxial layer, the first insulating layer, and a side wall of the trench; etching a part of the dielectric layer to form a dielectric region, where the dielectric region is located on the first insulating layer and the side wall of the trench; and forming a second insulating layer and a gate conductor in the trench, where the second insulating layer surrounds the gate conductor, fills the trench, and extends to the surface of the epitaxial layer.

Abstract: This invention relates to a high molecular weight nylon powder composition for 3D printing, its preparation method and use. The composition comprises: 100 parts by weight of high-viscosity nylon powder, 1-5 parts by weight of a flow agent, and 0.1-1 parts by weight of an antioxidant; the high-viscosity nylon powder is one or more selected from nylon 6, nylon 66, nylon 11, nylon 12, nylon 612 and nylon 610; or the powder composition is obtained via polymerization reaction of the raw materials comprising the following components, based on the weight parts of lactam monomers or amide monomers: 100 parts by weight of lactam monomers or amide monomers, 0.005-1 parts by weight of a catalyst, and 0.1-1 parts by weight of an antioxidant.

Abstract: The present invention provides a composition for 3D printing, a process for preparing the same and an article thereof. By the solidifying method of UV irradiation, 3D printing is implemented. During said implementation, there is no need of high temperature heating, thus energy consumption is reduced, and there is no need for special solvent, thus harm to the environment is reduced. Meanwhile, the present invention uses micro-nano powder as the main material and polymer resin as adhesive, and at the same time, adds irradiation sensitizer. After electron beam irradiation, the polymer resin forms three-dimensional crosslinked network, thereby the strength, heat resistance and chemical resistance are improved after resin adhesion.

Abstract: Provided are use of organosilane, and polyolefin resin and preparation method thereof. The method of preparing the polyolefin resin comprises: conducting olefin polymerization of olefin monomers in the presence of a catalyst, and adding organosilane to a polymerization system before the olefin polymerization and/or during the olefin polymerization, wherein the organosilane is represented by a general formula of R1mSiXn(OR2)k, wherein R1 is a C2-C20 alkyl, and a terminal of R1 has an ?-olefin double bond, a norbornene group, a cycloalkene group, or a dicyclopentadiene group; X is a halogen element; R2 is a C1-C20 straight chain, a C1-C20 branched chain, or an isomerized alkyl group; m is an integer from 1-3; n is an integer from 1-3; k is an integer from 0-2; and m, n, and k satisfy the following condition: m+n+k=4. The polyolefin resin obtained by the above method has higher melt strength and mechanical strength.

Abstract: The present invention provides modified olefin polymerization catalyst, preparation method thereof, olefin polymerization catalyst system, use thereof and method of preparing polyolefin resin. The catalyst comprises an olefin polymerization catalyst and an organosilane, which is represented by a general formula R1mSiXn(OR2)k, where R1 is a C2-C20 alkyl group and a terminal of R1 has an ?-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene group, X is a halogen element, R2 is a C1-C20 linear chain, branched chain or isomerized alkyl group, m is an integer from 1-3, n is an integer from 1-3, k is an integer within a range of 0-2, and m+n+k=4. High-performance polyolefin resins, including homopolymerized polyolefin resin with high melt and mechanical strength, polyolefin elastomer with high rubber phase content, and polyolefin elastomer with a rubber phase in a crosslinked structure, etc., can be obtained through polymerization with the catalyst.

Abstract: Provided are use of organosilane, in-reactor polyolefin alloy and preparation method thereof.

Abstract: An ultraviolet laser 3D printing device includes a thermostat, a laser head, a non-contact type temperature monitoring device, a scanning galvanometer, a processing platform, a powder laying device, a material to be processed, a computer control system. The device is configured to perform the following functions: presetting a processing temperature by the control system; during the processing procedure, the temperature rise condition of the processed object is monitored by the non-contact type temperature monitoring device and fed back in real time to the control system; and by recording the rise value of the temperature within a certain period, the system can obtain the absorption capability of the laser and the temperature rise degree of the processed material, so that the laser output power can be calculated according to the preset processing temperature value, and the laser power can be adjusted in real time to precisely control the processing temperature.

Abstract: The present invention provides modified olefin polymerization catalyst, preparation method thereof, olefin polymerization catalyst system, use thereof and method of preparing polyolefin resin. The catalyst comprises an olefin polymerization catalyst and an organosilane, which is represented by a general formula R1mSiXn(OR2)k, where R1 is a C2-C20 alkyl group and a terminal of R1 has an ?-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene group, X is a halogen element, R2 is a C1-C20 linear chain, branched chain or isomerized alykl group, m is an integer from 1-3, n is an integer from 1-3, k is an integer within a range of 0-2, and m+n+k=4. High-performance polyolefin resins, including homopolymerized polyolefin resin with high melt and mechanical strength, polyolefin elastomer with high rubber phase content, and polyolefin elastomer with a rubber phase in a crosslinked structure, etc., can be obtained through polymerization with the catalyst.

Abstract: Provided are use of organosilane, in-reactor polyolefin alloy and preparation method thereof.

Abstract: Provided are use of organosilane, and polyolefin resin and preparation method thereof. The method of preparing the polyolefin resin comprises: conducting olefin polymerization of olefin monomers in the presence of a catalyst, and adding organosilane to a polymerization system before the olefin polymerization and/or during the olefin polymerization, wherein the organosilane is represented by a general formula of R1mSiXn(OR2)k, wherein R1 is a C2-C20 alkyl, and a terminal of R1 has an ?-olefin double bond, a norbornene group, a cycloalkene group, or a dicyclopentadiene group; X is a halogen element; R2 is a C1-C20 straight chain, a C1-C20 branched chain, or an isomerized alkyl group; m is an integer from 1-3; n is an integer from 1-3; k is an integer from 0-2; and m, n, and k satisfy the following condition: m+n+k=4. The polyolefin resin obtained by the above method has higher melt strength and mechanical strength.

Abstract: The present disclosure disclosed an ultraviolet laser 3D printing method for the precise temperature control of polymer material and device thereof. The device comprises a thermostat, a laser head, a non-contact type temperature monitoring device, a scanning galvanometer, a processing platform, a powder laying device, a material to be processed, a computer control system and so on.

Abstract: The present invention provides a composition for 3D printing, a process for preparing the same and an article thereof. By the solidifying method of UV irradiation, 3D printing is implemented. During said implementation, there is no need of high temperature heating, thus energy consumption is reduced, and there is no need for special solvent, thus harm to the environment is reduced. Meanwhile, the present invention uses micro-nano powder as the main material and polymer resin as adhesive, and at the same time, adds irradiation sensitizer. After electron beam irradiation, the polymer resin forms three-dimensional crosslinked network, thereby the strength, heat resistance and chemical resistance are improved after resin adhesion.

Abstract: This invention relates to a high molecular weight nylon powder composition for 3D printing, its preparation method and use. The composition comprises: 100 parts by weight of high-viscosity nylon powder, 1-5 parts by weight of a flow agent, and 0.1-1 parts by weight of an antioxidant; the high-viscosity nylon powder is one or more selected from nylon 6, nylon 66, nylon 11, nylon 12, nylon 612 and nylon 610; or the powder composition is obtained via polymerization reaction of the raw materials comprising the following components, based on the weight parts of lactam monomers or amide monomers: 100 parts by weight of lactam monomers or amide monomers, 0.005-1 parts by weight of a catalyst, and 0.1-1 parts by weight of an antioxidant.

Abstract: The present invention belongs to the field of polyolefin alloy preparation, and particularly relates to a polyolefin composite material in good form with adjustable composition and performances, produced by controlling a composite catalyst composed of Zieglar-Natta catalyst and metallocene catalyst to be catalytic by stage in the olefin polymerization reaction. This material is composed of propylene polymer and ethylene copolymer which is obtained by copolymerizing ethylene with alpha olefin or diolefin, wherein: the molar content of alpha olefin or diolefin in the ethylene copolymer is 0%˜60%, and the ethylene copolymer is 3˜80% by weight of the polyolefin composite material; the polyolefin composite material is in particle form, and the ethylene copolymer has a molecular weight distribution of 1˜6 and a glass transition temperature of ?80˜0° C.; and the ethylene copolymer produced in the reaction is dispersed homogeneously in the propylene polymer particles to form the polyolefin composite material.

Abstract: A process for preparing polypropylene compositions having high impact strength at low temperatures is disclosed in which the reaction is catalyzed by Ziegler-Natta/metallocene hybrid catalysts by the in-situ polymerization of one or more olefins of the formula CH2?CHR, in which R is hydrogen or an alkyl, cycloalkyl or aryl group having from 1 to 10 carbon atoms, and more specifically comprises preparing an olefin polymer by Ziegler-Natta catalyst components of the titanium or vanadium/metallocene hybrid catalysts while the metallocene components are inactivated beforehand by catalyst inactivators; and polymerizing one or more olefins in the presence of the above olefin polymer, followed by a reactivation of the metallocene components.

Abstract: The invention relates to a process for preparing polyolefin graft copolymers (II) from linear and well defined polyolefin copolymers (I) containing divinylbenzene comonomer units, wherein R, in formulas I and II, is a C1 to C10 linear or branched alkyl group or a C6 to C10 substituted or unsubstituted aromatic group; and wherein G and G′, independantly, are selected from —H, —OH, epoxy, —NH2, —COOH, anhydride, —Cl, —Br, —M, —COOM (M=metal, e.g., Li, Na, K and Ca) or a polymer chain having the molecular weight of at least about 500, which can be derived from both step and chain polymerization reactions. G and G′ can be selected singly or in a combination of two or more thereof. In the graft copolymer composition, the combined alpha-olefin mole .% (x+y) is from about 50 to 99.9 mole %. Preferably, x+y is from 85 to 99.9 mole %, and most preferably x+y is from 95 to 99.9 mole %.

Abstract: The invention relates to linear copolymers containing alpha-olefin and divinylbenzene comonomer units and to a process for preparing the copolymers, the copolymers having a mole ratio of unsaturation/divinylbenzene (TUS/DOU) between 0.8 and 1.1, a molecular weight distribution of less than 4, and a homogeneous composition distribution, and having the structural formula ##STR1## in which R is a linear or branched C.sub.1 to C.sub.10 alkyl group or a phenyl or alkyl-substituted phenyl group, x+y is the mole % of alpha-olefin units in the copolymer, z is the mole % of divinylbenzene units in the copolymer, the sum of x+y is from 50 to 99.9, and the sum of x+y+z is 100. The copolymers are prepared in the presence of a bridged metallocene catalyst having a spacial opening at the metal active site of between 135 and 105.degree. for reacting with only one of the two vinyl groups in the divinylbenzene comonomer, which assures the formation of linear copolymers without detectable branching structure.