150 results about "Thermostability" patented technology

The invention discloses a flame-retardant thermoplastic polyurethane elastomer material and a preparation method thereof, and belongs to the technical field of modified nano materials. The preparation method comprises the following steps: dissolving melamine, phytic acid and boron nitride in deionized water, carrying out oil bath, adding a coupling agent, stirring, carrying out vacuum filtration, washing with water, and drying to obtain a layered nano flame retardant; the preparation method comprises the following steps: dispersing a flame retardant in deionized water containing a nonionic dispersant, and carrying out ultrasonic treatment; the preparation method comprises the following steps: reacting polyether polyol with diisocyanate to obtain a primary prepolymer; adding other auxiliary agents, stirring, and carrying out gradient heating polymerization; and injecting into a mold, curing for 6-12 hours at 105-125 DEG C, and drying for 12-24 hours at 80-90 DEG C. A phosphorus-nitrogen-silicon ternary synergistic flame-retardant system is introduced, the boron nitride nanosheet surface grafting and dynamic pre-polymerization-gradient heating process is optimized, the dispersity is improved, and smoke suppression and thermal stability are achieved. Compared with the prior art, the flame retardant efficiency is high, the mechanical property is excellent, and environmental friendliness is achieved.

The invention relates to the technical field of flame-retardant materials, and particularly discloses a full-bio-based reactive flame retardant, a zero-VOC bio-based basic flame-retardant waterborne polyurethane emulsion and a preparation method of the zero-VOC bio-based basic flame-retardant waterborne polyurethane emulsion. According to the invention, vanillin, lysine and phytic acid are taken as raw materials, a full-bio-based reactive flame retardant is synthesized, and the full-bio-based reactive flame retardant can form chemical bonding with a waterborne polyurethane matrix, so that intrinsic flame retardance is realized. A molecular structure of the cosolvent contains a plurality of high-activity groups such as hydroxyl groups, the cosolvent has excellent thermal stability and lasting flame-retardant efficiency, can be chemically bonded with a waterborne polyurethane matrix under a low-temperature condition, remarkably reduces the dosage of the cosolvent, and can realize zero VOC solvent emission when being applied to a chemical flame-retardant modification process of waterborne polyurethane. Meanwhile, the Schiff base group contained in the flame retardant endows the flame retardant with an extra antibacterial function, breeding of microorganisms on the surface and inside of the material can be inhibited after the flame retardant is combined with waterborne polyurethane, material degradation caused by microbial erosion is avoided, the service life of the material is prolonged, and the using effect of the material is improved.

The application discloses a low-viscosity nitrogen-modified flame-retardant and smoke-suppressing silicone oil and a preparation method thereof, relates to the technical field of modified silicone oil, and the flame-retardant and smoke-suppressing silicone oil is obtained by ring-opening addition reaction of double-end epoxy silicone oil and methyl urea. The nitrogen-containing group is introduced into the polysiloxane molecule in a reactive form by adopting the chemical modification of methyl urea on the end epoxy silicone oil, so that the flame-retardant and smoke-suppressing performance and the thermal stability of the silicone oil are improved without significantly sacrificing the material fluidity. The obtained low-viscosity nitrogen-modified flame-retardant and smoke-suppressing silicone oil still maintains a good flow state at normal temperature, and is convenient to use in the modification of high polymer materials, the blending of composite systems and subsequent processing applications.

The present invention relates to novel esterases, and more particularly to esterase variants having improved activity and / or improved thermal stability compared to the parent esterase of SEQ ID NO: 1 or SEQ ID NO: 2 under acidic conditions and their use for degrading polyester-containing materials, such as plastic articles. The esterase of the present invention is particularly suitable for degrading polyethylene terephthalate and materials containing polyethylene terephthalate under acidic conditions.

The invention provides a synthetic method of a novel flame retardant with a phosphaphenanthrene-chloropropyl synergistic structure. The preparation method comprises the following steps: synthesizing bis (1-chloro-2-propyl) phosphoryl chloride from phosphorus oxychloride and epoxypropane in a molar ratio of 1: 2 in a low-temperature condition through a micro-channel reactor, reacting with DOPO-HQ (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-yl-1, 4-benzenediol), adding a specific solvent and a catalyst, reacting to generate a crude product, filtering, washing, carrying out reduced pressure distillation, and recrystallizing to obtain the 2-(1-chloro-2-propyl) phosphoryl chloride, namely the 2-(1-chloro-2-propyl) phosphoryl chloride-DOPO-HQ (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-yl-1, 4-benzenediol). The novel flame retardant with the phosphaphenanthrene-chloropropyl synergistic structure is obtained. A phosphaphenanthrene-chloropropyl synergistic structure is designed, so that the molecular weight and the phosphorus content are improved, and the gas-phase flame-retardant and condensed carbon-forming synergistic flame-retardant effect is improved; the thermal stability and the molecular weight are improved through a molecular bridge chain (hydroquinone), and migration is inhibited. The flame retardant has excellent flame retardant property.

The invention relates to the technical field of bioengineering and environmental biology, and particularly discloses high-temperature-resistant polylactic acid depolymerases and application thereof in degradation of polylactic acid plastics. The nucleotide sequence of the coding gene of the high-temperature-resistant polylactic acid depolymerases B01 is as shown in SEQ ID NO: 1, and the amino acid sequence of the coding gene is as shown in SEQ ID NO: 2. The enzyme is derived from metagenome mining, the sequence similarity of the enzyme and the known PLA depolymerases PAM is only 34.45%, and the enzyme has remarkable novelty. According to the present invention, the secretory expression and the purification of the B01 are successfully achieved in the bacillus subtilis SCK6; an enzymatic property research shows that the optimal reaction temperature of the B01 is 65 DEG C, the half-life period at 60 DEG C is as long as 150 minutes, and the B01 shows excellent thermal stability; and the optimum pH value of the strain is 9.0. The invention provides a novel enzyme preparation with important application potential for high-temperature biological recovery treatment of PLA plastic waste.

The invention discloses a crystalline porous organic molecular framework material POM-OFPDT constructed by non-covalent pi accumulation as well as a preparation method and application of the crystalline porous organic molecular framework material POM-OFPDT. The crystalline porous organic molecular framework material POM-OFPDT constructed by non-covalent pi stacking provided by the invention has a capsule-shaped permanent one-dimensional pore channel in the a-axis direction, has good thermal stability, recyclability and high selectivity, and can effectively realize efficient separation of aromatic hydrocarbons / cycloalkanes.

The invention belongs to the technical field of high polymer materials, and particularly discloses a preparation method of a high-strength anti-aging plastic material. The method aims at solving the problems that a poly (butylene succinate) (PBS) material is poor in hydrolysis resistance, prone to ultraviolet aging and insufficient in thermal stability. The method comprises the following steps: premixing 60-80 parts by weight of PBS and 10-20 parts by weight of specifically compounded polylactic acid; then adding nano titanium dioxide, an antioxidant and a light stabilizer, and carrying out high-speed mixing; doping 1-3 parts by weight of a polycarbodiimide anti-hydrolysis agent and 2-5 parts by weight of a benzotriazole ultraviolet light absorber at a low temperature; carrying out melting reaction extrusion on the mixture and the epoxidized soybean oil through a double-screw extruder at the temperature gradient of 150-185 DEG C; and finally, carrying out underwater pelletizing, rapid cooling, vacuum deep drying and programmed heating annealing stabilization treatment to obtain a final product which has excellent mechanical strength, long-acting hydrolysis resistance, high ultraviolet aging resistance and thermal stability and is suitable for the high-performance fields of outdoor precise instruments, automobile exterior trimming parts and the like.

The invention relates to the technical field of catalyst preparation and discloses a skeleton type iron-based molecular sieve as well as a preparation method and application thereof. The method comprises the following steps: (1) in the presence of a solvent, pre-reacting an Fe source, an M source and a zeolite molecular sieve, and drying to obtain a precursor; (2) calcining the precursor at the temperature of 500 DEG C or above for the first time, and then performing thermal modification in a hydrogen-containing atmosphere to obtain Fe / M seed crystal; and (3) mixing the Fe / M seed crystal with a silicon source, an aluminum source and a template agent, carrying out hydrothermal treatment, separating, drying, and carrying out secondary calcination at 500 DEG C or above to obtain the skeleton type iron-based molecular sieve. Through the synergistic effect of a hydrogen reduction seed crystal method and specific auxiliary metal, the skeleton type iron-based molecular sieve catalyst which has the denitration efficiency of 87% or above at the high temperature of 650 DEG C and has excellent cycle stability and high-temperature hydrothermal stability is successfully prepared.

The application relates to the technical field of biodegradation, in particular to a method for degrading polyester materials by using a heat-stable leaf branch compost lignin esterase based on coordination modification of rare earth ions. The application significantly improves the thermal stability and catalytic efficiency of the enzyme by using the coordination strategy of rare earth ions and developing enzyme mutants with enhanced coordination, and the polyester materials are completely degraded within 8 hours. Meanwhile, the application simplifies the synthesis and purification steps of the enzyme, directly uses the crude enzyme to efficiently degrade the polyester materials at high temperatures, reduces the reaction cost, and realizes the biological recovery of polyester monomer raw materials. Compared with the traditional biodegradation method, the application has higher efficiency, lower cost and better environmental compatibility. The enzyme modification strategy not only promotes the progress of enzyme engineering technology, but also provides a new perspective for the fields of environmental protection and new material development, and has broad application potential and social value.

The invention discloses a high-temperature-resistant degradable polypropylene bio-based composite material and a preparation method thereof, and relates to the technical field of degradable plastics. The preparation method comprises the following steps: by adopting PEG modified straw powder instead of conventional unmodified straw as a biomass filler, firstly soaking the straw powder in PEG, so that the straw powder interacts with cellulose / hemicellulose in the straw through hydrogen-bond interaction; and then carrying out heat treatment to promote a dehydration condensation reaction between PEG terminal hydroxyl groups and straw components to form stable chemical bonding, so that a heat-resistant protective layer is constructed on the surface of the straw, and a long-chain shielding effect is generated. Through modification, the thermal stability of the straw can be remarkably improved, the surface polarity is reduced, and the interfacial compatibility of the straw and a polypropylene matrix is enhanced, so that the mechanical property and the heat resistance of the composite material are remarkably improved, and the problems that the straw is poor in interface bonding and easy to thermally decompose in the polypropylene-based material are effectively solved. The method is simple in process, environmentally friendly and low in cost, and an efficient way is provided for high-value utilization of agricultural waste.

This invention provides a polymer composite membrane for isolating nanoscale solid materials and its preparation process. The polymer composite membrane includes a mechanical support layer and a filter layer coated on the surface of the mechanical support layer. The filter layer and the mechanical support layer are bonded together by a phase inversion method. In this invention, a cross-linked structure is formed at the interface between the support layer and the filter layer through a photothermal curing reaction. This cross-linked structure has high mechanical strength and can prevent the filter layer from falling off. The filter layer of this invention has a dense layer structure, which can block solid particles larger than a few nanometers at the membrane surface, allowing only water molecules to pass through the membrane. The mechanical support layer has a microporous structure, which utilizes carboxylated nanofiber crystals to combine with doped amino carbon nitride through an amidation reaction, thereby improving the mechanical strength and thermal stability of the composite membrane and significantly improving the retention capacity and retention efficiency of the composite membrane.

The invention discloses a preparation method of a novel bio-based copolyester material, and belongs to the field of green high polymer materials. According to the method, a furan carboxylic acid source, a pentanediol source and glutaric acid are used as raw materials, and the poly (neopentyl glycol glutarate-co-neopentyl glycol furandicarboxylate) series random copolyester is synthesized through ester exchange and condensation polymerization. The method comprises the following operation steps: mixing a furan carboxylic acid source, a pentanediol source and glutaric acid according to a molar ratio, adding a catalyst, sequentially carrying out heating reaction in an inert gas atmosphere, carrying out vacuum polycondensation, dissolving and precipitating, and drying to obtain a target product. The obtained copolyester material is controllable in composition and stable in structure, and has good thermal stability (Tdmaxgt; the glass transition temperature (4-64 DEG C) is adjustable, the mechanical property is excellent, the highest elongation at break can reach 917%, and the Young modulus can reach 1963 MPa. The material performance can be continuously regulated and controlled along with the monomer feeding ratio, and the material has wide application prospects in the aspects of elastomers, high-barrier thermoplastic materials and the like. The method is simple in process, raw materials are easy to obtain, and the method is suitable for sustainable development of the high-performance full-bio-based plastic.

The invention belongs to the field of recycling of precious metal resources in environmental engineering, and particularly relates to a preparation method and application of an organic polymer sphere adsorbent. The amidoxime modified self-polymerized microporous polymer (AO-PIM-1) is prepared into the spherical adsorbent through a phase inversion method, and compared with other traditional adsorbents, the polymer sphere adsorbent is high in specific surface area and good in thermal stability and water stability and has a large number of functional groups with high combining capacity for Au ions. In a low-concentration Au solution, a good adsorption effect and excellent adsorption selectivity are still kept, and Au ions in electronic waste leachate can be well adsorbed and recycled.

The invention discloses a long-side-chain internal-plastic toughened polyurethane elastomer as well as a synthesis method and application thereof, and belongs to the technical field of high-performance elastomers. According to the invention, a long side chain toughening element is introduced as a cohesive reinforcing unit, binary hydrazide is adopted as a chain extender for cooperation, and the long side chain toughening element reacts with an isocyanate prepolymer to construct a strong hydrogen bond cross-linked polymerization network. The structure integrates the processability / stretchability / low temperature resistance of the flexible chain segment and the high toughness / thermal stability / chemical resistance of the long side chain toughening element. By regulating and controlling the component proportion of the soft chain segment, the stretchability and mechanical toughness of the material can be balanced and rejected, so that high Td and chemical resistance are maintained, and on the premise of not reducing the modulus and tensile strength of the material, the low-temperature toughness is improved, the combination of rigidity and toughness is realized, and the defect of insufficient toughness of the existing commercially available polyurethane elastomer is overcome.

The present application belongs to the field of food contact coating materials, and provides a food contact grade silicone emulsion and a preparation method thereof. The silicone intermediate with a core-shell emulsion droplet structure is synergistically compounded with a methyltrimethoxysilane surface modified silica intermediate, and combined with hydrolysis and condensation pre-emulsification, high pressure homogenization, aging, defoaming, filtration and control of emulsion droplet and particle size distribution to obtain a water-based system with stable dispersion and workability. The system still maintains suitable viscosity under higher non-volatile conditions, and after film formation, it has the performances of adhesion, wear resistance, heat resistance and stable release, solving the problem that the existing system cannot simultaneously consider high solid content, low viscosity, processing adaptability, high adhesion, wear resistance and film forming performance, and high heat resistance, stability and low release force. The present application has application value in constructing a silicone release layer on the surface of paper base material and plastic film base material.

This invention relates to engineered plastic-degrading enzymes with improved functional features. In particular, modified PETases capable of hydrolysis of PET or polyethelene terephthalate plastic polymer are disclosed herein. These engineered PETases contain one or more amino acid modifications at specified residue or residues, for example, N233, and exhibit improved enzymatic activity as well as therrnostability.

The present invention relates to novel esterases, more particularly to esterase variants having improved activity and / or improved thermostability compared to the esterase of SEQ ID NO: 1 and the uses thereof for degrading polyester containing material, such as plastic products. The esterases of the invention are particularly suited to degrade polyethylene terephthalate, and material containing polyethylene terephthalate.

The invention discloses a radiation-resistant sealing composition based on an end-group functionalized elastomer as well as a preparation method and application of the radiation-resistant sealing composition, and belongs to the technical field of high polymer materials and radiation protection. The composition comprises the following components in parts by weight: 100 parts of an end group functionalized elastomer, 15-60 parts of a radiation-resistant filler, 1-8 parts of a cross-linking agent and 0.5-5 parts of a processing aid, wherein the end group functionalized elastomer is obtained by modifying hydroxyl-terminated polybutadiene or fluorinated elastomer by an end group modifier containing a naphthalene ring, an anthracene ring or a phenanthrene ring, and the radiation-resistant filler comprises a composite system of a radiation shielding filler and a free radical capturing filler. According to the invention, by combining the conjugated structure design at the molecular terminal with the synergistic effect of the composite filler, the sealing material keeps good processing and mechanical properties, and the high-dose irradiation resistance, thermal stability and compression permanent deformation resistance are remarkably improved; the sealing device is particularly suitable for sealing systems in high-end fields such as nuclear reactors, spacecrafts and medical equipment.

The invention discloses a PC / PBT (polycarbonate / polybutylene terephthalate) modified plastic and a preparation method thereof in the technical field of modified plastics. The PC / PBT modified plastic comprises the following components in parts by weight: 70-80 parts of PC, 20-30 parts of maleic anhydride modified polybutylene terephthalate (maleic anhydride modified PBT) and 15-20 parts of a reinforcing agent. High strength and heat stability are provided through PC, the rigidity and size stability of the material are improved through PBT, the reinforcing agent is dispersed in a phase interface to form a soft-phase toughening area, impact energy is absorbed, crack propagation is prevented, multiple reaction sites form a chemical bond cross-linked structure, and the impact performance and heat resistance are further improved.

The invention relates to the field of chemical engineering, in particular to a bio-based hindered phenol antioxidant and a preparation method thereof. According to the bio-based hindered phenol antioxidant provided by the invention, a tert-butyl group with relatively large steric hindrance is arranged at the ortho-position of a hydroxyl group, a linear alkyl group (C15H31-) is arranged on a benzene ring, and the tert-butyl group and the linear alkyl group jointly regulate and control the activity of a phenolic hydroxyl group, so that the bio-based hindered phenol antioxidant has very good solubility in a non-polar medium (such as polyolefin plastics as polyethylene PE, polypropylene PP and the like); the compatibility is improved, volatilization and migration precipitation are reduced, and the thermal stability and the antioxidant activity are greatly improved. Moreover, the adopted raw material cardanol is a bio-based material and is safe and environment-friendly, and the preparation method is simple and easy to implement, mild in condition and beneficial to large-scale production.

The application discloses vanillyl octyl ester, a preparation method and application thereof, and relates to the field of insulating oil additives. Vanillyl acid and n-octanol are subjected to esterification under the action of a biological enzyme catalyst to synthesize vanillyl octyl ester, and the synthesis method is efficient, green, environmentally friendly and low in cost. The prepared vanillyl octyl ester is added into synthetic ester insulating oil as an antioxidant active ingredient, the long ester chain in the vanillyl octyl ester has high thermal stability, can effectively inhibit the oxidation of the synthetic ester insulating oil at high temperature, and has good compatibility with the synthetic ester insulating oil. Therefore, compared with traditional antioxidants, the vanillyl octyl ester has significant advantages in maintaining excellent antioxidant properties and electrical properties of the synthetic ester insulating oil.

This invention relates to the field of polymer degradable materials technology, specifically to a biodegradable material, its preparation method, and its applications. The material is based on modified polylactic acid (PLA), supplemented by antioxidants, plasticizers, flame retardants, and inorganic fillers in specific weight proportions. Its unique feature lies in the polymerization of lactic acid and epicatechin imidazole ammonium chloride polymer under stannous octoate catalysis, using chemical bonding to introduce the bioactive groups of epicatechin into the PLA backbone, significantly improving the material's biodegradation rate, mechanical properties, and thermal stability. The bioactive substances and ionic groups in this material promote microbial degradation, achieving complete decomposition in a composting environment within a short time. Simultaneously, through molecular-level reinforcement and ionic cross-linking effects, the strength, toughness, and high-temperature processing performance of PLA are effectively improved. This material can be widely used in disposable tableware, food packaging films, and biodegradable agricultural mulch films.

The invention belongs to the field of biotechnology and enzymology, and particularly relates to a thermostable variant of MDH and application thereof. The amino acid sequence of the mutant is shown as any one of SEQ ID NO: 1 to SEQ ID NO: 23. The catalyst has a normal MDH catalysis function and shows high temperature stability. The thermal stability variant of MDH provided by the invention can be used for replacing traditional MDH to be applied to clinical diagnostic reagents, cold-chain transportation and low-temperature storage are avoided, the cost is reduced, and the shelf life is prolonged.

The invention discloses a method for synthesizing nano-enzyme with ascorbic acid oxidase and catalase double-enzyme activity based on an iron-doped zinc-based metal organic framework material. The zinc-based metal organic framework material is a porous coordination high-molecular polymer crystal formed by coordination of zinc ions and organic ligands. The metal organic framework material is rich in active sites, large in specific surface area, adjustable in structure, large in porosity and remarkable in catalytic performance. Furthermore, the metal organic framework material is used as a precursor and is calcined and pyrolyzed in inert gas such as argon or nitrogen or air to synthesize a novel porous material, and the novel porous material has relatively large specific surface area, good thermal stability and chemical stability and unique catalytic performance. The invention discloses a method for synthesizing a unique nano-enzyme with ascorbic acid oxidase and catalase double-enzyme activity by using an iron-doped zinc-based metal organic framework material as a precursor and calcining the iron-doped zinc-based metal organic framework material in an inert gas atmosphere at a high temperature, and the method has the advantages of simplicity in operation, simple procedure and the like.

The invention relates to the technical field of high polymer material processing, in particular to a preparation method of an insulating and fireproof high-tensile PET (polyethylene terephthalate) flame-retardant film for a battery module, which comprises the following steps: S1, weighing all components according to a preset proportion, and uniformly mixing to form a premixed modified material; s2, carrying out melt copolymerization reaction on the premixed modified material to form a modified PET copolymer; s3, the modified PET copolymer is melted and then subjected to tape casting processing, and a primary membrane material is prepared; s4, carrying out tension heating pretreatment; s5, carrying out synchronous longitudinal and transverse stretching treatment to obtain a high-strength flame-retardant film; s6, carrying out heat setting treatment; s7, the surface is coated with an electric insulation coating; and S8, static elimination and constant-tension rolling are conducted, and a finished product is obtained. According to the invention, the PET film with high tensile strength, dimensional stability and flame-retardant and insulating properties is prepared through synergistic modification and integrated processing technologies, and the defects of existing materials in the aspects of thermal stability and function coordination are overcome.