20results about How to "Raise the crystallization temperature" patented technology

The invention discloses modified thermoplastic polyurethane elastomer foamed beads and a preparation method and application thereof, and the preparation method comprises the following steps: (1) stirring and mixing a thermoplastic polyurethane elastomer, a long-carbon-chain polyamide thermoplastic elastomer and a processing aid, and then extruding and granulating to obtain modified thermoplastic polyurethane elastomer foamed particles; (2) putting the foaming particles and water into a high-pressure reaction kettle, stirring, then filling supercritical fluid, heating the high-pressure reaction kettle to the softening temperature of the foaming particles of the modified thermoplastic polyurethane elastomer, and enabling the modified thermoplastic polyurethane elastomer to reach a saturated state, so as to obtain a polymer-supercritical fluid homogeneous system; and (3) performing pressure relief foaming on the polymer-supercritical fluid homogeneous system to obtain the modified thermoplastic polyurethane elastomer foamed beads. The prepared modified thermoplastic polyurethane elastomer foamed beads are high in setting rate and low in shrinkage rate, the foaming processing efficiency is remarkably improved, and a foamed material which is round in appearance, low in density and high in resilience is obtained.

The invention relates to a large-breadth thermoplastic polyolefin impermeable geomembrane and a preparation method thereof, and the preparation method comprises the following steps: uniformly mixing a thermoplastic polyolefin composite material, feeding the thermoplastic polyolefin composite material into a screw extruder, melting and plasticizing the thermoplastic polyolefin composite material by the screw extruder, extruding the thermoplastic polyolefin composite material into a mold for molding at a low temperature, then pulling the thermoplastic polyolefin composite material to advance, and naturally cooling the thermoplastic polyolefin composite material in the advancing process to obtain the large-breadth thermoplastic polyolefin impermeable geomembrane. And enabling the material to complete partial crystallization process, and then entering a three-roller calender for thickness determination, thereby obtaining the large-breadth thermoplastic polyolefin impermeable geomembrane. The breadth of the prepared geomembrane is larger than or equal to 6 m, the transverse and longitudinal elongation difference is small, and the large-breadth thermoplastic polyolefin anti-seepage geomembrane can be suitable for the high-pressure water environment.

The application discloses a method for improving crystallization ability of semi-aromatic nylon and modified semi-aromatic nylon. The method comprises the following steps: mixing semi-aromatic nylon and an alkaline solution, and preparing the modified semi-aromatic nylon after heat treatment; the mass ratio of the alkali in the alkaline solution to the semi-aromatic nylon is greater than or equal to 0.005:1; the alkali in the alkaline solution comprises hypophosphite, phosphite, phosphate or alkali metal salt; and the temperature of the heat treatment is greater than 60 DEG C. The method can improve the crystallization ability of the semi-aromatic nylon without adding nucleating agents, additives and the like, for example, improving the crystallization ability of the semi-aromatic nylon under the conditions that the polymerization process and the polymer molecular weight are determined.

The application relates to the technical field of high polymer materials, and discloses a nylon material and a preparation method and application thereof. The nylon material comprises the following preparation raw materials in percentage by mass: 70-85% of nylon resin, 8-15% of nitrogen-based flame retardant, 2-8% of phosphorus-based flame retardant and 1-8% of synergistic flame retardant. The nylon material provided by the application adds the phosphorus-based flame retardant and the synergistic flame retardant in a traditional nitrogen-based flame retardant system, so that the ignition temperature of the material is increased, the dropping speed and the dropping ignition probability are reduced, and the flame retardant performance of the material is improved. The ignition temperature of the material can reach 745 DEG C, the DSC crystallization temperature can reach 187 DEG C, the demolding effect is good, the dropping speed is slow, the dropping ignition probability is low, the performance requirements of a battery assembly product on the material can be met, and the nylon material can be used in the preparation of electronic connectors, battery compartments, low-voltage switches, housings or terminal blocks of power distribution systems of electronic and electrical equipment.

The invention relates to a gate material, a semiconductor device and a memory. The gate material comprises a base material and a doping element doped in the base material. The base material comprises a chalcogenide amorphous compound, and the doping element is at least bonded and connected with a chalcogenide element in the chalcogenide amorphous compound to form a complete tetrahedral structure and / or octahedral structure. The doping element is added into the matrix material of the gating material, so that the content of the stable tetrahedral structure and / or octahedral structure in the gating material is increased, the amorphous thermal stability of the gating material can be effectively improved, the current control capability of the gating layer is improved, and the performance of the gating layer is improved. Therefore, the reliability of the semiconductor device with the gating layer is improved, and the power consumption of the semiconductor device is reduced.

The invention belongs to the technical field of biodegradable polyester materials, and relates to a preparation method of biodegradable polyester fibers, which comprises the following steps: uniformly mixing a reaction type auxiliary agent and biodegradable polyester, carrying out melt spinning to obtain pre-oriented fibers, and carrying out hot drafting and heat setting on the pre-oriented fibers to obtain the biodegradable polyester fibers. The reaction type auxiliary agent is one or more of haplotype carbodiimide and polymeric carbodiimide; the mass ratio of the reaction type auxiliary agent to the biodegradable polyester is (0.5: 99.5)-(5.0: 95.0). According to the method, the crystallization temperature of the biodegradable polyester is increased, the adhesion between tows in the processing process of the biodegradable polyester fiber is avoided, the condition is mild, the operation is simple, and the method is suitable for large-scale industrial application.

The invention provides a polypropylene-based foaming material and a preparation method thereof, and relates to the technical field of preparation of foaming materials. The invention relates to a preparation method of a polypropylene-based foaming material, which comprises the following steps: adding polypropylene and water into a container, introducing high-pressure CO2 gas, heating to 130-145 DEG C while stirring, and keeping constant temperature and constant pressure so that the system is completely saturated; releasing the pressure within 3-10 seconds, and cooling to 40-50 DEG C to obtain the polypropylene-based foaming material. The polypropylene-based foaming material is excellent in foaming performance.

The method for preparing polyoxalate by ring-opening polymerization of cyclic oxalate monomers and cyclic oligomers thereof disclosed by the application is that at least one of the cyclic oxalate monomers and the cyclic oligomers thereof, or a blend of at least one of the cyclic oxalate monomers and the cyclic oligomers thereof and at least one of cyclic lactone, cyclic lactide and cyclic carbonate, is subjected to bulk ring-opening polymerization or solution ring-opening polymerization under the action of a catalyst and an initiator to obtain polyoxalate and its copolymer. Since the application adopts ring-opening polymerization to prepare polyoxalate, not only the problems of low esterification polycondensation efficiency and poor polymerization controllability are avoided, but also the side reactions of alpha-keto acid decarboxylation and terminal hydroxyl group etherification in the esterification polycondensation process are avoided, so that the polyoxalate obtained has controllable polymerization degree / molecular weight, high structural regularity and clear end group structure, and further has higher melting point and crystallization temperature and is white, and at the same time, a new way for preparing polyoxalate is provided.

The application belongs to the technical field of polymer materials, and particularly relates to a kind of methylene furan-containing aromatic skeleton double urea nucleating agent, heat-resistant polylactic acid composition and a preparation method thereof. A series of methylene furan-containing aromatic skeleton double urea polylactic acid nucleating agents are prepared by a green route using non-isocyanate as raw material, and a furfurylamine derived from biomass by a one-pot two-step method. In the polylactic acid composition, the mass content ratio of polylactic acid and nucleating agent is 100:0.1-5. Dry polylactic acid and methylene furan-containing aromatic skeleton double urea nucleating agent are mixed by a double-screw mixer at 150-220 DEG C for 3-15 min. The polylactic acid composition modified by the nucleating agent has a significant improvement in crystallization rate and crystallinity, and the heat resistance is further enhanced, so the composition has a good industrialization prospect.

The invention relates to a high-molecular high-efficiency nucleating agent as well as a preparation method and application thereof. The polymeric nucleating agent of the present invention comprises a cross-linked polymer comprising a structural unit derived from a photosensitive monomer having a dynamic cross-linking group. The molecular structure of the high-molecular nucleating agent is similar to that of a polymer to be nucleated, the high-molecular nucleating agent further comprises a photosensitive structural unit with a dynamic cross-linking group, cross-linking is performed through ultraviolet irradiation after molecular crystallization of the nucleating agent, so that a topological structure after crystallization of a high-molecular chain is fixed, and the cross-linked polymer is used for the nucleating agent and can remarkably improve the crystallization rate. The nucleating agent provided by the invention has efficient nucleating ability, good dispersibility and thermal stability.

The invention provides a nucleating agent as well as a preparation method and application thereof. The structure of the nucleating agent is shown as a formula I, the nucleating agent belongs to an organophosphate compound nucleating agent in an alpha nucleating agent, contains a benzene ring and a carbon-carbon triple bond, has relatively good thermal stability, and ensures that the nucleating agent is not molten, not decomposed and in a microparticle shape at a polymer melting point of EVOH in a subsequent application process of preparing the EVOH; meanwhile, the para-position and the carbon-carbon triple bond of the benzene ring are connected with polar groups, so that the whole nucleating agent shows polarity and can be uniformly dispersed in polar EVOH. Furthermore, a polar group in a carbon-carbon triple bond, namely, R1 contains a flexible rotatable functional group, so that the flexibility of the EVOH crystal substance can be improved. The EVOH with excellent comprehensive performance can be obtained by adding a small amount of EVOH into the EVOH.

The invention provides a phase change material and a memory. The phase change material comprises a base material, an Hf element and an A element. The element A comprises at least one of N, O and Si. The phase change material can improve the operation speed and durability of the memory at the same time.

The invention relates to a semiconductor device, a memory and a memory system, the semiconductor device comprises a gate layer with a bidirectional threshold switching characteristic, and the material of the gate layer comprises a main body material and a first doping material doped in the main body material. Both the main body material and the first doping material contain chalcogenide compounds, and the first doping material has a stable tetrahedral structure in an amorphous state. According to the semiconductor device, the first doping material with the stable tetrahedral structure in the amorphous state is doped in the main body material of the gate layer, so that the amorphous thermal stability of the gate layer material can be effectively improved, the stability of the electrical property of the gate layer is improved, and the reliability of the semiconductor device is further improved.

The invention discloses a hydrophilic syndiotactic polypropylene composite material with high crystallization temperature and a preparation method thereof. The composite material comprises the following components in parts by weight: 85-98 parts of syndiotactic polypropylene; 2 to 8 parts of polyvinylidene fluoride; 0-5 parts of polyethylene; and 0-8 parts of polyvinyl alcohol. The syndiotactic polypropylene composite material can be obtained by premixing the components through a high-speed mixer and then mixing and granulating through a double-screw extruder. Polyvinylidene fluoride has excellent crystallization performance and can be used as a crystallization promoting component to induce folding attachment crystallization of sPP molecular chains, the crystallization performance of sPP is improved, and meanwhile the hydrophilic performance of sPP is improved. And blending addition components such as high-density polyethylene and polyvinyl alcohol are added, and the characteristics of all the components are comprehensively utilized, so that the sPP is endowed with more excellent hydrophilic performance while the crystallization performance of the sPP is remarkably improved. The invention not only provides a brand new choice for sPP crystallization promoting components, but also expands the application field of sPP due to the brought excellent hydrophilic performance.

The invention discloses a preparation method of a polypropylene-based lead shielding gamma-ray composite material with excellent processability, and belongs to the field of ionizing radiation shielding materials. The technical problems that existing conventional polypropylene and metal particles are poor in compounding compatibility, low in melt strength and high in processing difficulty are solved. The method comprises the following steps: taking polypropylene as a matrix, polybutadiene nano rubber as a reinforcement, acrylamide as a compatilizer and lead oxide as shielding metal particles; the polypropylene-based lead composite material with long-chain branching characteristics, uniform lead oxide particle dispersion, high thermal stability and good gamma-ray shielding performance and processability is prepared through a wet reaction melt blending method. The method is easy to operate, the polypropylene-based lead composite material can have the long-chain branching characteristic, the forming processing performance is improved, lead oxide particles are evenly dispersed, the crystallization temperature is increased, the thermal stability is improved, and the shielding performance is excellent. The prepared composite material is applied to the field of ionizing radiation protection with limited space and maneuverability.

The invention relates to a low-supercooling-degree settable composite phase change material and a preparation method and application thereof in a heat energy storage technology. The invention belongs to the field of phase change energy storage materials. The problems that the sugar alcohol phase change material is in an amorphous liquid state during melting, the crystallization temperature is low and the degree of supercooling is high are solved. The low-supercooling-degree settable composite phase change material disclosed by the invention is prepared from expanded graphite, erythritol powder and mannitol powder according to a reasonable ratio. The prepared composite phase change material improves the crystallization temperature, reduces the degree of supercooling, is good in shaping state after a high-temperature test, is simple in preparation process, convenient to operate, short in preparation period, simple and harmless in preparation process, and beneficial to industrial production, and the raw materials are safe, non-toxic and low in price. And the method has remarkable social benefits and economic benefits.

The invention discloses a gating device material and a memory. The gate device material includes a base material and a doping material. The base material comprises an As element and an Se element. The doping material comprises an element A, and the element A is selected from at least one of C, Si and N. The molar percentage content of each element A in the gating device material is greater than 0% and less than or equal to 10%. A proper amount of A element is doped in the matrix material, and the amorphous stability of the gating device material is improved, so that the current control capability of the gating device material is improved, the risk of misoperation on the phase change storage layer is reduced, and the data reliability of the memory is improved.

The invention relates to the technical field of high polymer materials, in particular to a high-strength PBS biodegradable plastic and a preparation method thereof.The high-strength PBS biodegradable plastic is prepared from 4000-5000 parts of succinic acid, 5000-6000 parts of 1, 4-butanediol, 0.9-22 parts of a first catalyst and 4.5-550 parts of a functional additive; wherein the functional aids comprise a first functional aid and a second functional aid; the first functional additive comprises at least one of polyethylene wax, polypropylene wax and oxidized polyethylene wax; the second functional additive is selected from one of a formula (I) or a formula (II); the weight ratio of the first functional additive to the second functional additive is (0.5-3): 1; according to the high-strength PBS biodegradable plastic prepared by selecting a specific functional aid and a catalyst to be matched with the raw materials, the crystallization temperature of the PBS plastic is increased, the crystallization speed is increased, meanwhile, the tensile strength and the high-temperature resistance of the PBS plastic are improved, the hydrophobicity of the PBS plastic is enhanced, and therefore the degradation time of the PBS plastic is prolonged.

The invention relates to the technical field of high polymer materials, and discloses a low-density biodegradable composite material based on an interface pore effect and a preparation method. The composite material is prepared from a resin matrix composed of poly (butylene adipate / terephthalate) and polypropylene carbonate, modified activated plant fibers, a high-melting-point heterogeneous crystallization nucleating agent and a matrix reinforcing chain extender, wherein the surfaces of the modified activated plant fibers are grafted with nano rigid particles, and the modified activated plant fibers are passivated by polyethyleneimine. The preparation method comprises the following steps: firstly, grafting nano particles on the surface of the fiber through a silane coupling agent, passivating, and then reacting and extruding under a high vacuum condition through a double-screw extruder with the length-diameter ratio of greater than or equal to 52: 1. According to the invention, the density of the material is reduced on the premise of not adding a chemical foaming agent by utilizing an interface micropore nucleation principle, meanwhile, the problem of matrix degradation caused by plant fibers is solved, and the composite material with the characteristics of light weight, high strength and full biodegradation is obtained.

The invention discloses a bio-based indole acid zinc salt nucleating agent, which is prepared by reacting an indole acid compound with an acid zinc substance; the nucleating agent of the invention is mixed with polylactic acid by a melt blending method, and is extruded or injection molded into a polylactic acid product, which can provide good nucleation efficiency for polylactic acid during the preparation process, and the nucleation effect is very stable, and the obtained polylactic acid product has the characteristics of biodegradability, excellent mechanical properties and excellent antibacterial properties. This type of nucleating agent has a simple preparation method, and the raw materials are derived from bio-based materials, which has the potential for sustainable development. It is not only easy to achieve large-scale production, but also can provide excellent antibacterial properties for polylactic acid products, and can expand the application field of polylactic acid plastic products.