18results about How to "Reduce yellowing" patented technology

The application discloses an anti-ultraviolet aging polycarbonate modified material and application thereof, and belongs to the technical field of polymer material modification. The material comprises synergistically modified polycarbonate, an organic small-molecule functional regulator, an antioxidant, a light stabilizer, a lubricating dispersant and an inorganic filler, wherein the synergistically modified polycarbonate is constructed into a multiple synergistic network by introducing a borate dynamic covalent structure, a Schiff base structure and a rare earth coordination structure, and the organic small-molecule functional regulator is p-hydroxybenzophenone. The preparation method comprises preparation of the synergistically modified polycarbonate and a subsequent melt blending and extrusion process. Through the technical scheme, the synergistic effect of ultraviolet absorption, energy transfer and free radical inhibition is realized, the yellowing degree of the material is significantly reduced, the mechanical property retention rate and the optical stability are improved, and the material is suitable for the fields of automobile transparent parts, outdoor optical materials and electronic and electrical shell.

The invention relates to the technical field of building waterproof composite materials, in particular to an organic silicon modified resin building waterproof composite material and a preparation method thereof. Comprising a waterproof roll and a waterproof coating arranged on the surface of the waterproof roll, the waterproof coating is prepared from the following components in parts by weight: 20 to 32 parts of silane modified polyether, 15 to 30 parts of organic silicon modified resin, 5 to 10 parts of polysaccharide-based composite polylactic acid, 8 to 12 parts of plasticizer, 1 to 3 parts of curing agent, 0.5 to 2 parts of titanium dioxide and 0.5 to 3 parts of water removal agent. An organic silicon structure in the prepared waterproof composite material has the characteristic of low surface energy, so that the surface of a coating presents strong hydrophobicity, and liquid water permeation is effectively blocked; the waterproof coating can be matched with a compact cross-linked network structure to form a continuous and seamless waterproof film, realizes high hydrostatic pressure resistance and low water absorption, and is suitable for key waterproof parts such as roofs, basements and toilets.

The application discloses a kind of high-performance outdoor full package imitation wood composite board and preparation method thereof, relate to polyurethane composite board technical field, the full package imitation wood composite board includes base board, and the polyurethane material of setting in the lower surface and the four around of base board, and the resin material of setting in upper surface.Its preparation method includes the following steps: pouring polyurethane material in the silica gel mould after surface treatment, place base board, mould pressing, make the polyurethane material with wood texture around and lower surface of base board composite, obtain intermediate product A;Resin material is rolled on the upper surface of intermediate product A, and is dried, to obtain full package imitation wood composite board;The silica gel mould after surface treatment is prepared by transferring real solid wood board texture.

The application provides a self-repairing silicone resin and a preparation method thereof, OCA optical glue containing the self-repairing silicone resin and application of the self-repairing silicone resin. The self-repairing silicone resin contains a disulfide bond and a mercapto group in a molecular structure. The content of the disulfide bond in the self-repairing silicone resin is greater than 0.6 mmol / g. The self-repairing silicone resin is used for preparing OCA optical glue. While ensuring high light transmittance, low yellowing and good mechanical properties of the OCA optical glue, the self-repairing silicone resin can improve the initial adhesion of the OCA optical glue, and can also endow the OCA optical glue with a self-repairing function and improve the repair efficiency.

The invention relates to the technical field of high polymer materials, and particularly discloses anti-yellowing polyester resin for an MDF plate and a preparation method of the anti-yellowing polyester resin. An antioxidant unit and a formaldehyde reactive unit are simultaneously bonded on a molecular chain of the polyester resin through covalent bonds, and the two functional units are connected to a polyester main chain through flexible chain segments. The preparation method comprises the following steps: firstly, synthesizing a difunctional linking agent of which one end contains an antioxidant group, the other end contains a formaldehyde reactive group and the middle is connected by a flexible chain segment; and carrying out melt polycondensation reaction on the coupling agent serving as an end-capping reagent or a comonomer, polyhydric alcohol and polybasic acid to obtain the target resin. The problems of migration, loss and failure caused by traditional physical addition of small-molecule auxiliaries are fundamentally solved, so that when the obtained polyester resin is used for an MDF plate facing coating, lasting and efficient hot-pressing yellowing resistance and weather yellowing resistance can be provided, the free formaldehyde release amount of a plate can be continuously captured and reduced, and the service life of the plate is prolonged. The decorative property and the environment-friendly property are both improved.

The application belongs to the technical field of thermoplastic elastomer modification, and discloses a silane coupling agent modified thermoplastic elastomer and a preparation method thereof, and aims to solve the technical defects of the existing thermoplastic elastomer, such as uncoordinated strength and toughness, poor temperature change resistance, insufficient ultraviolet stability, and poor comprehensive performance coordination. The modified thermoplastic elastomer is prepared by compounding a thermoplastic elastomer base material, a silane coupling agent modification liquid, a boron nitride-kaolin combined agent and other auxiliary agents according to specific weight parts. The preparation process of the application is simple and controllable, the obtained modified thermoplastic elastomer has balanced strength and toughness, a wide temperature change resistance range, excellent ultraviolet stability and outstanding comprehensive performance.

The present application relates to a kind of photocuring composition and its preparation method and application, the photocuring composition includes the following components: resin, active monomer and photoinitiator.The photocuring composition described in the present application has low photoinitiator mobility, good solubility of photoinitiator in monomer, low energy required when the photocuring composition is cured, high adhesion on the surface of various substrates such as plastic, metal and other difficult to adhere substrates, and the photocuring composition has low odor during curing process, low yellowing degree after curing, high stability and repeatability of the system, and excellent comprehensive performance.

The invention discloses soybean endophyte HML5368, application of the soybean endophyte HML5368 and a plant leaf spraying agent, the soybean endophyte HML5368 is named as Bacillus cereus according to taxonomy and is preserved in China General Microbiological Culture Collection Center on September 23, 2024, and the preservation number of the soybean endophyte HML5368 is CGMCC NO: 32043. In the invention, the soybean endophyte HML5368 is found and separated by the inventor for the first time, the secreta of the soybean endophyte HML5368 serves as an effective component of the plant leaf spraying agent, the benefit of the soybean endophyte HML5368 on plant growth is reserved, the soybean endophyte HML5368 can be used for other plants except soybeans, the requirement of the endophyte on specificity is avoided, and the application prospect is wide. The endophyte has important significance in popularization and application of the endophyte in crops.

The present application discloses an ethylene-vinyl alcohol copolymer (EVOH) resin composition, which is prepared by polymerization and alcoholysis reaction, and the content of EVOH with ethylene content less than 15 mol% is less than 3 wt%. The present application also discloses a preparation method of the EVOH resin composition. The EVOH resin composition prepared by the present application has the content of EVOH with ethylene content less than 15 mol% less than 3 wt%, and the processing performance is significantly improved, the yellowing at high temperature is obviously reduced, and the defect number after melt blowing is reduced; thus the multilayer sheet, film and container prepared by the present application do not have crystal point, stripe and other defects.

The polymer of the present application is represented by the following general formula (P). In general formula (P), Y is a 1 to 6-valent organic group having 1 or more and 30 or less carbon atoms derived from a thiol group-containing compound having 2 or more functional groups, Chain contains a structural unit represented by the following general formula (AE-1) and a structural unit represented by the following general formula (AE-2), and n is an integer of 1 to 6.

This invention relates to a salt tolerance-related protein, LcCIPK25, and its encoding gene in hybrid tulip tree (Liriodendron tulipifera), and its applications, belonging to the field of plant genetic engineering technology. The amino acid sequence of this protein is shown in SEQ ID NO.2, and the nucleotide sequence of the gene encoding this protein is shown in SEQ ID NO.1. This invention also provides a recombinant expression vector containing the aforementioned nucleic acid molecule, a recombinant host cell, and its application in improving plant salt tolerance. Overexpression of the aforementioned nucleic acid molecule in hybrid tulip tree can maintain CAT activity, alleviate leaf yellowing and oxidative damage under high salt stress, significantly reduce MDA content, and effectively enhance the plant's salt tolerance.

This invention provides polymer particles that exhibit reduced yellowing upon heating. Because the polymer particles of this invention are formulated to have a cumulative percentage of 17% or less of particles with a diameter of 60% or less of the median diameter in a particle size distribution based on particle number, and to keep the number of small-diameter particles in a certain proportion or less, the yellowing of the polymer particles due to heating is reduced. Therefore, these polymer particles can prevent products containing these polymer particles from discoloring due to the yellowing of these polymer particles, and are thus suitable for use in the production of products for optical applications.

The present application discloses an ethylene-vinyl alcohol copolymer (EVOH) resin composition, which is prepared by ethylene-vinyl acetate copolymerization reaction, and the content of polyvinyl alcohol in the EVOH resin composition is less than 5000 ppm. The present application can reduce the content of polyvinyl alcohol in the EVOH resin composition, thereby improving the yellowing resistance and processing stability of the EVOH resin composition in the melting process, and the prepared multilayer sheet, film and container are not prone to have defects such as crystal points and stripes.

The present application relates to the field of daily chemical products, and discloses a light-color transparent odorless concentrated sterilization bead content, which comprises the following components in percentage by mass: p-chloro-m-xylenol 15-25%, non-ionic surfactant 0-5%, anionic surfactant containing at least C21 dibasic acid 10-20%, alcohol solvent containing at least isohexyl alcohol 43-55%, inorganic alkali agent 3-5%, bacteriostatic agent 0-2%, essence 0-2%, and water in remainder amount. The concentrated sterilization bead content of the present application uses inorganic alkali to replace organic amine alkali agent, so that the product appearance is stable and transparent light color under low cost conditions; the present application uses the combination of "non-ionic surfactant+C21 dibasic acid+isohexyl alcohol" to replace alcohol and ether solvents, so that the p-chloro-m-xylenol is significantly solubilized under the premise of no odor and safety.

The invention belongs to the technical field of waterproof coiled material preparation, and particularly relates to a weather-resistant polyethylene waterproof coiled material and a preparation method thereof. Epoxy functionalized polytetrahydrofuran ether glycol is doped into traditional bisphenol A-based epoxy resin, poly epsilon-caprolactone particles and fumed silica are added to prepare an adhesive, and the adhesive is combined with a polyethylene base material to obtain the weather-resistant polyethylene waterproof coiled material. The polytetrahydrofuran ether glycol and the poly epsilon-caprolactone particles synergistically improve the anti-aging performance and the waterproof performance of the adhesive, and the fumed silica improves the strength reduction of the epoxy resin in the modification process and improves the rheological property, so that the coiled material can meet the application requirements of outdoor and wet base layers and other harsh working conditions.

This invention belongs to the field of tissue culture technology and provides a method for rapid propagation of Tibetan Saussurea involucrata via tissue culture, comprising the following steps: From May to July, Tibetan Saussurea involucrata explants are subjected to stepwise sterilization to obtain sterile explants; these explants are inoculated into a starter culture medium for seed germination to obtain callus tissue; the callus tissue is transferred to MS proliferation medium containing 2.0-3.0 mg / L 6-BA + 0.05-0.1 mg / L IAA, and cultured for 21-25 days. TDZ is then added to promote shoot differentiation, while simultaneously reducing IAA to 0.01-0.02 mg / L, and cultured for another 21-25 days to obtain rootless seedlings; these seedlings are then transferred to rooting medium and cultured for 21-25 days to obtain tissue culture seedlings; after hardening off the seedlings for 2-4 days, they are transplanted into a sterile substrate. This method significantly improves the propagation stability and seedling quality of Tibetan Saussurea involucrata via tissue culture by quantifying key process parameters and establishing a multi-dimensional evaluation system.

This invention relates to the field of laser cutting technology and discloses a laser cutting device for copper plates used in copper crafts processing. The device includes a laser cutting machine housing and a laser cutting head. Y-axis linear motors are mounted on both sides of the top of the laser cutting machine housing, and a portal frame is positioned between the Y-axis linear motors. An X-axis linear motor is fixed to one side of the top beam of the portal frame. The laser cutting head is fixed to one end of the slide. A fixing ring is fixed to the lower half of the outer wall of the laser cutting head, and an external gear ring is fixed to the outside of the fixing ring. This invention achieves a 360° adjustable preheating and rapid cooling mechanism around the laser cutting head, allowing it to follow the cutting direction of the laser cutting head in real time. This ensures that the electric heating plate always precisely covers the area to be cut, and the hollow water-cooled housing always precisely covers the cutting area, achieving seamless integration of preheating, cutting, and rapid cooling. This maximizes the effects of preheating and rapid cooling, further improving cutting accuracy and cut quality.

This invention discloses an ethylene-vinyl alcohol copolymer resin composition and its application. The resin composition contains less than 5000 ppm of polyvinyl alcohol and less than 3 wt% of EVOH (ethylene content <15 mol%). This resin composition exhibits excellent processing properties, significantly reduces yellowing at high temperatures, and decreases the number of defects after melt blown film production; thus preventing defects such as crystal points and streaks from appearing in the produced multilayer sheets, films, and containers.