73results about How to "Improve hot water resistance" patented technology

Disclosed is a composite ceramic which is composed of a bulk alumina crystal phase (A) having an aspect ratio of not more than 3, a bulk zirconia crystal phase (B) having an aspect ratio of not more than 3 and a columnar crystal (C) of a complex oxide containing an alkaline earth metal and aluminum element which has an aspect ratio of more than 3. This composite ceramic has excellent flexural strength, excellent toughness, high hardness, excellent hot water resistance, and high transverse strength after thermal degradation resistance test.

The invention belongs to the technical field of polyester preparation, and discloses a modified PET copolyester with high viscosity and a low terminal carboxyl group and a preparation method and application thereof. The copolyester contains the following ingredients in parts by weight: 100 parts of low-viscosity PET copolyester, 0.8-2.0 parts of oxazoline compound and 0.6-2.0 parts of a hydroxyl chain extender. The method prepares the high-viscosity modified PET copolyester by adding the oxazoline compound and the hydroxyl chain extender. The oxazoline compound is added to react with the terminal carboxyl group in resin, the terminal carboxyl group content of resin is reduced, therefore, the hot water resisting performance of resin is increased. The hydroxyl chain extender is added, the molecular weight of resin is increased, and the balance between a physical performance and a processing performance is achieved. The viscosity and the melt strength of the modified PET copolyester are increased, the content of terminal carboxyl group is reduced, and the hot water resisting performance is greatly increased. Moreover, the production method shortens the polycondensation time and the production cycle, effectively reduces the thermal degradation reaction, and also increases the output of equipment.

The invention belongs to the technical field of polyesters and discloses a modified aliphatic-aromatic copolyester having high viscosity and low carboxyl end group content and its preparation method and use. The modified aliphatic-aromatic copolyester comprises, by weight, 100 parts of a low-viscosity aliphatic-aromatic copolyester, 0.5-3 parts of an oxazoline compound and 0.4-2.5 parts of a hydroxyl chain extender. Through use of the oxazoline compound and the hydroxyl chain extender, the modified aliphatic-aromatic copolyester is prepared. The used oxazoline compound and the carboxyl end group in the resin undergo a reaction so that resin carboxyl end group content is reduced and resin hot-water resistance is improved. Through use of the hydroxyl chain extender, resin molecular weight is improved and the balance of physical properties and processing properties is realized. Viscosity and the melt-strength of the modified aliphatic-aromatic copolyester are improved, carboxyl end group content is reduced and hot-water resistance is improved. The preparation method has a short production period, reduces polycondensation time and effectively reduces thermal degradation reactions.

The invention provides a hydrolysis resistant high temperature resistant thermoplastic polyester elastomer composition including 100 parts by weight of polyester elastomer (A); 0.01-10 parts by weight of poly carbodiimide (B); 0.01 to 0.5 part by weight of a phenolic heat stabilizer (C); 0.01 to 0.5 part by weight of a thio ester heat stabilizer (D); and 0.01 to 0.5 part by weight of an aromatic amine heat stabilizer (E). The hydrolysis resistant high temperature resistant thermoplastic polyester elastomer composition still can effectively maintain the tensile strength and elongation at break in the long time exposure to hygrothermal environment, after 90 days of hydrolysis resistance test of the composition dipping in hot water at the temperature of 95 DEG C, the tensile strength is maintained above 25Mpa, the elongation at break is remained above 482%; and after 168h of heat resistance test at the temperature of 158 DEG C, the tensile strength is maintained above 81%, so that the hydrolysis resistant high temperature resistant thermoplastic polyester elastomer composition can be applied in higher-end areas.

The invention relates to a processing process of high-modulus low-shrinkage high-colour-fastness polyester filament yarn by direct melt spinning and real-time injection. By the special design of steps including subjecting a polyester raw material to shrinkage reducing processing, performing modulus-increasing blending and melting melt processing, performing low-frequency real-time compression and injection, subjecting the melt to multi-stage direct-melting and spinning, passing through a filter screen, spinning, cooling, applying oil, stretching, and the like, and by special optimization of related parameters, the technical difficult problems of fiber in the prior art, namely low modulus, low strength and poor natural-color fasteness are overcome, and the objective of purification, high color fasteness, high modulus and low shrinkage is achieved. Under the obvious improvement on the high color fasteness, the high modulus and the low shrinkage which are good properties, stability, thermal resistance, resistance to hot water, elasticity resilience, elongation and homogeneity are largely improved.

The invention discloses a modified gelatin fiber. Characteristic absorption peaks appear nearby 3290 cm<->, 1628 cm<->, 1527 cm<-> and 1230 cm<-> in the infrared spectrum of the gelatin fiber. The gelatin fiber is prepared by dissolving gelatin in a solvent for swelling and then to mixing with a cross-linking agent, then adding a mixed material obtained in the previous step into spinning equipment so as to obtain nascent fiber, and subjecting the nascent fiber to aftertreatment. According to the invention, transglutaminase is used as the cross-linking agent which is safe to use; and the prepared gelatin fiber has good stability in water and improved mechanical properties and is applicable to the fields of biology and medicine.

The invention relates to a composite material and a preparation method thereof. The preparation method comprises the steps of slowly adding the following components in parts by weight: 80-90 parts of amination-enhanced modified straw, 1-10 parts of oxidized graphene and 1-10 parts of cyclodextrin into deionized water with the bath ratio of 1 to (10-20), and carrying out ultrasonic treatment for 1-24h; and then, carrying out freeze drying to obtain the amination-enhanced modified straw/oxidized graphene/cyclodextrin composite material. According to the invention, the amination-enhanced modified straw/oxidized graphene/cyclodextrin composite material is prepared by loading oxidized graphene and cyclodextrin on the amination-enhanced modified straw serving as a carrier, and then, carrying out freeze drying. The composite material has the advantages of environmental friendliness, good mechanical property, regular structure, high porosity and adsorption capacity, high adsorption speed, wide application range, simplicity in desorption, reutilization and the like.

An EPDM composition, which comprises a blend rubber comprising 100 parts by weight of blend rubber consisting of 20-80% by weight of EPDM containing 5-ethylidene-2-norbornene [ENB] as one type of diene component and 80-20% by weight of EPDM containing dicyclopentadiene [DCPD] as another type of diene component, and 0.5-10 parts by weight of an organic peroxide. Seal parts obtained by vulcanization molding of the EPDM composition show well balanced characteristics, even if dipped in hot water at high temperatures such as 200° C. for 500 hours or 300° C. for 24 hours, particularly with improved compression set characteristics.

The invention discloses a formalizing method of high-strength and high-modulus polyvinyl alcohol fiber, which comprises the following steps: (1) preparing a swelling medium: dissolving 1-50 parts by weight of additive in 100 parts by weight of water and stirring to obtain the swelling medium; (2) pre-swelling the fiber: feeding the polyvinyl alcohol fiber bundle into the swelling medium to be swelled, wherein the temperature of the swelling medium is 20-80 DEG C and the swelling time is 10 to 60 minutes; and (3) formalizing the swelling fiber bundle: formalizing the swelled fiber bundle in an aldehyde condensation solution, wherein the formalizing temperature is 40-90 DEG C and the formalizing time is 10-40 min. The formalized polyvinyl alcohol fiber can be manufactured into short fiber or filament after being processed. The formalized high-strength and high-modulus polyvinyl alcohol fiber can be purely spun or blended with other fibers to manufacture textile threads and fabrics with various specifications, which are used for manufacturing high-strength wear-resistant work clothes, training clothes, tents, backpacks, ropes and the like, and has good popularization and application prospects.

The invention discloses special powder paint with good water resistance and weather resistance for a pump valve. The powder paint is prepared from the following raw materials in parts by weight: 52-54 parts of hydroxyl polyester resin, 7-8 parts of fluorocarbon resin, 4-5 parts of triglycidyl isocyanurate, 13-15 parts of nano-aluminium oxide, 0.8-0.9 part of perfluoro octyl triethoxysilane, 25-30 parts of an ethanol solution with the concentration of 75 wt%, 0.5-0.6 part of a silane coupling agent kh560, 1.5-2 parts of an antioxidant 264, 0.8-0.9 part of a polyacrylate levelling agent, 2-2.5 parts of emulsified asphalt, 2-3 parts of iron oxide red, 7-9 parts of waste glass, 9-11 parts of superfine light calcium carbonate, 0.8-1 part of aminopropyltriethoxysilane and a proper amount of water. The powder paint is low in production cost, easy for powder coating, and good in water resistance and weather resistance, and has a good protection effect on the pump valve material working under permanently humid environment.

A membrane-electrode assembly having superior hot water resistance has a membrane containing an aromatic polymer having a repeating unit expressed by general formula (1):

in which A represents independently either —CO— or —SO₂—; B represents independently an oxygen atom or sulfur atom; R¹ to R⁸, which may be identical or different from each other, represent a hydrogen atom, fluorine atom, alkyl group, phenyl group or nitrile group; R⁹ to R²⁴, which may be identical or different from each other, represent a hydrogen atom, alkyl group or phenyl group; and ‘a’ represents an integer of 0 to 4.

The invention relates to an amination-enhanced modified straw based composite material and a preparation method thereof. The preparation method comprises the following steps of slowly adding the following components in parts by weight: 80-90 parts of amination-enhanced modified straw, 1-10 parts of oxidized graphene and 1-10 parts of alginate into deionized water with the bath ratio of 1 to (10-20), and carrying out ultrasonic treatment for 1-24h; and then, carrying out calcium ion crosslinking and freeze drying to obtain the amination-enhanced modified straw/oxidized graphene/alginate composite material. According to the invention, the amination-enhanced modified straw/oxidized graphene/alginate composite material is prepared by loading oxidized graphene and the alginate on the amination-enhanced modified straw serving as a carrier, and then, carrying out calcium ion crosslinking and freeze drying. The composite material has the advantages of environmental friendliness, good mechanical property, regular structure, high porosity and adsorption capacity, high adsorption speed, wide application range, simplicity in desorption, reutilization and the like.

The invention discloses a method for producing direct melt filtration fused direct spun ultrafine denier polyurethane fibers. The method is characterized by comprising the following steps of: proportioning raw material components, feeding materials under negative pressure, applying 0.8MPa nitrogen pressure, extruding by a twin-screw extruder, filtering by a melt filter, cooling spun filaments by an air channel, oiling by an oiling machine, curing by a drying room, and detecting and packing. The invention has the advantages that: the ultrafine denier polyurethane fibers have small bending stiffness, soft handfeel and large surface area; the coverage, bulkiness and heat retention of a fabric are remarkably improved, and the fabric has strong cleaning function; the ultrafine fibers are prepared into an ultra-dense fabric, a gap among the fibers is between the diameter of a water drop and the diameter of a water vapor microdrop, and the ultra-dense fabric has a waterproof and ventilated effect; and the ultrafine fibers are processed into a towel fabric which can be wetted by water, and the towel fabric has high water absorption, and water of washed hair can be rapidly absorbed by using the towel, so that the hair is rapidly dried. The method can be applied to various fields.

The invention discloses powder coating having an excellent antirust effect and used for a pump valve. The powder coating is prepared from raw materials in parts by weight as follows: 52-54 parts of polyester resin, 7-8 parts of fluorocarbon resin, 4-5 parts of triglycidyl isocyanurate, 13-15 parts of nano aluminum oxide, 0.8-0.9 parts of perfluoro octyl triethoxysilicane, 25-30 parts of an ethanol solution with the concentration being 75wt%, 0.5-0.6 parts of a silane coupling agent kh560, 0.8-1 part of polyethylene wax, 1.2-1.5 parts of a polyacrylate leveling agent, 6-8 parts of superfine zinc powder, 2-3 parts of an ethylene-chlorotrifluoroethylene copolymer, 2-3 parts of polyvinylpyrrolidone, 13-15 parts of barium sulfate, 3-4 parts of mica iron oxide and a proper amount of water. The powder coating has excellent comprehensive performance, the film forming speed is high, the antirust effect of the powder coating is further improved due to addition of the superfine zinc powder and mica iron oxide, and a coating layer is tough and firm and not prone to peeling, has a smooth surface and is free of pinholes, safe and environment-friendly.

The invention provides a method for producing melt direct spinning superfine (4.6-5.5) denier high elastic modulus polyurethane fibers, which is characterized by comprising the following steps: raw materials, charging under negative pressure, addition of 0.8MPa nitrogen pressure, high-temperature spontaneous reaction in two static reactors in turn, a double-screw extruder, filtration in a melt filter, jetted yarn cooling in an air duct, oiling by an oiling machine, curing in a drying room and detecting and casing. The method has the following advantages: the superfine denier polyurethane fibers have low bending stiffness and quite soft feel; the surface areas of the fibers are large, thus obviously improving the coverage, bulkiness and heat retention of the fabrics and having extremely strong cleaning function; the superfine fibers are made into superhigh density fabrics and the size of the gaps between the fibers range from the diameter of the water drops to the diameter of the vapor droplets, thus having waterproof and non-airproof effects; and the superfine fibers are processed into such fabrics which can be moistened by water as towels and the towels have high water absorbability and can rapidly absorb the moisture of the washed hairs to rapidly dry the hairs. The method can be applied in various fields.

The invention provides a water-based wood lacquer basic sticking material. The water-based wood lacquer basic sticking material is prepared from the following components: modified ABS (Acrylonitrile Butadiene Styrene) resin, modified water-soluble rosin resin, a modified specific acrylate monomer, a modified general acrylate monomer, a siloxane low-polymer water solution, a water-soluble amino/vinyl functional group siloxane copolymerized oligomer, a siloxane monomer, a chain transfer agent, a reaction type emulsifier, an azo initiator, de-ionized water, a pH (Potential of Hydrogen) regulator, adhesion promoting resin, a water-based chelate and a water repellent agent. The invention further provides a preparation method of the water-based wood lacquer basic sticking material. By adopting the water-based wood lacquer basic sticking material provided by the invention, the quality effect can be get close to oily wood lacquer.

The invention discloses a preparation method of a polyester grafted polyacrylate polymer for a transparent powder coating, which comprises the following steps of: proportioning acrylate and glycidyl methacrylate by a certain mass ratio, adding a solvent into a three-neck flask which is provided with a stirrer, a thermometer, a reflux condenser, a two-neck connecting pipe and a constant pressure dropping funnel, dropwise adding a mixed solution of the glycidyl methacrylate, the acrylate and an initiator into the flask at the temperature of 100-130 DEG C, reacting for a period of time, and vacuumizing to obtain a polyacrylate leveling agent; adding a solvent into a three-neck flask provided with a stirrer, a thermometer and a reflux condensing tube, heating to 100-110 DEG C, dissolving polyester into the solvent, dropwise adding the polyacrylate leveling agent, and after finishing reacting, vacuumizing to obtain the products polyester resin, polyester resin grafted polyacrylate and polyacrylate, so that the flatting agent has certain compatibility in a coating film; and the effects of smoothness, transparency and high-humidity-heat environment resistance of the coating film are achieved.