8results about How to "Improve thermo-oxidative stability" patented technology

The invention relates to light dehydrofluorination modified PVDF (polyvinylidene fluoride) resin as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving PVDF resin to be modified in a polar solvent to obtain a PVDF solution; the method comprises the following steps: adding weak organic alkali into a PVDF solution in a protective gas atmosphere, and then carrying out dehydrofluorination modification; and after the reaction is finished, terminating the reaction by using an acidic alcohol solution, and carrying out precipitation, washing and drying to obtain the light dehydrofluorination modified PVDF resin. Compared with the prior art, the high-temperature-resistant PVDF resin with high thermal stability and good melt processability can be obtained, and the high-temperature-resistant PVDF resin can be used for 200-DEG C-grade injection molding or extrusion molding products.

This application belongs to the technical field of high-temperature resistant foam materials, and specifically relates to a high-temperature resistant polymethacrylamide (PMI) foam material, its preparation method, and its applications. Addressing the deficiency of existing PMI foam materials where mechanical properties rapidly degrade at high temperatures, this application introduces maleimide monomers into the PMI foam material to improve the rigidity of the molecular chain segments. Then, through a crosslinking reaction between carboxyl groups and polyisocyanates, a high-temperature resistant PMI foam material is obtained. The PMI foam material exhibits excellent mechanical strength and a low rate of mechanical property degradation at high temperatures, enabling it to withstand loads and maintain structural dimensional stability under high-temperature conditions, making it suitable for use as a structural core material in the aerospace field.

This invention discloses a low-smoke halogen-free flame-retardant network cable and its preparation method, comprising a conductor, an insulation layer, a foamed filler strip, an aluminum-plastic composite film wrapping layer, a non-woven fabric wrapping layer, and a halogen-free flame-retardant outer sheath layer. The halogen-free flame-retardant sheath layer is prepared from the following components: ethylene-vinyl acetate copolymer, POE, pretreated magnesium hydroxide, ammonium polyphosphate, modified lignin, attapulgite, zinc borate, maleic anhydride-grafted ethylene-vinyl acetate copolymer, antioxidant, and calcium stearate. This low-smoke halogen-free flame-retardant network cable uses an EVA / POE blend as the sheath matrix and employs a ternary composite flame-retardant system of magnesium hydroxide, ammonium polyphosphate, and modified lignin, synergistically using zinc borate and attapulgite as functional additives. Without introducing halogens, the sheath material simultaneously possesses B1-level flame-retardant performance, low-smoke and low-toxicity characteristics, and transmission performance meeting the Category 6 network cable standard. The overall solution balances the requirements of flame-retardant safety and communication functionality.

The application belongs to the technical field of battery separator, and provides a PE material for lead-acid battery separator and a preparation method thereof.The PE material comprises the following raw materials in parts by weight: 20-24 parts of high molecular weight polyethylene, 58-76 parts of modified silicon dioxide, 10-18 parts of process oil, and 0.3-1.0 parts of antioxidant; the modified silicon dioxide is obtained by modifying the surface of silicon dioxide with diethylenetriamine and modified tannic acid.The PE material prepared by the application has high wettability, good mechanical strength and chemical stability, and meets the requirements of PE separator for lead-acid battery in practical application.

The invention discloses a preparation method of washable hot-fix rhinestone sizing powder, and relates to the field of functional surface decoration sizing powder. By optimizing the composite resin system and adding the hindered phenol antioxidant, the washing resistance and bonding strength of the adhesive layer are remarkably improved. Compared with the prior art, after the rubber powder is repeatedly washed for multiple times under the washing condition of 50 DEG C, the hot fix rhinestone can still be firmly attached to the surface of a base material, and falling off, edge warping or cracks do not occur. The rubber powder is suitable for various base materials and hot-fix rhinestone types, and can keep higher stability in industrial production. The matched application process defines the parameter ranges of hot fix rhinestone pretreatment, glue powder spreading amount, pre-curing and hot pressing, and ensures the consistency and quality stability of the product in large-scale production.

This application relates to an aging-resistant cable, comprising a conductor and an insulation layer. The insulation layer comprises the following components: polyvinyl chloride (PVC), cerium dioxide, lauric acid, 4-amino-2,2,6,6-tetramethylpiperidine, benzoylacetone, oxaloyl chloride, triethylamine, anhydrous ethanol, an antioxidant, and an ultraviolet absorber. It also relates to a processing method for the aging-resistant cable. This application has the following advantages and effects: The reaction of cerium dioxide with lauric acid allows metal ions and carboxyl groups to form coordinate bonds, achieving chemical anchoring and generating hydrophobic rare earth carboxylates, improving compatibility with PVC, inhibiting nanoparticle aggregation, promoting uniform dispersion, and providing thermal and light stabilization. Furthermore, the reaction of 4-amino-2,2,6,6-tetramethylpiperidine, benzoylacetone, and oxaloyl chloride yields a free radical scavenging ability with metal chelating capacity and hindered amines, enhancing the thermal and photo-oxidative aging resistance of the PVC cable material.

The invention discloses a high-temperature-resistant hot melt adhesive and a preparation method thereof, and relates to the technical field of hot melt adhesives. The high-temperature-resistant hot melt adhesive is prepared from the following raw materials in parts by weight: 25 to 35 parts of modified polyimide resin, 20 to 30 parts of modified benzoxazine resin, 8 to 12 parts of carboxyl-terminated nitrile rubber, 5 to 8 parts of C5 / C9 copolymerized petroleum resin, 3 to 5 parts of hydrophobic modified nano silicon dioxide, 1 to 2 parts of silicone powder, 0.5 to 1.0 part of antioxidant 1010, 0.3 to 0.8 part of zinc stearate and 0.05 to 0.1 part of tetrabutylammonium bromide. The high-temperature-resistant hot melt adhesive is scientific in raw material ratio, core resin is modified to improve heat resistance and compatibility, filler such as hydrophobic nano silicon dioxide is added to enhance performance, the preparation process is controllable, nitrogen protection is achieved in the whole process, moisture absorption is prevented through granulation and drying treatment, and a finished product is excellent in high-temperature resistance, good in comprehensive performance and good in storage stability.

The invention discloses pentaerythritol tetra (6-naphthyl hexanoic acid) ester and a preparation method and application thereof, the preparation method adopts two-step reaction of alkylation and esterification, the first step is that naphthalene and 5-hexenoic acid are subjected to alkylation reaction to generate 6-(1-naphthyl) hexanoic acid; and 2, carrying out a reaction on the 6-(1-naphthyl) hexanoic acid and thionyl chloride, and carrying out an esterification reaction with pentaerythritol to finally obtain the oily pentaerythritol tetra (6-naphthyl hexanoic acid) ester. The prepared pentaerythritol tetra (6-naphthyl hexanoate) ester has a structure with a symmetric four-arm core, a flexible alkyl chain and a rigid naphthalene end group, is shown as a formula (I), is used for lubrication and sealing of various equipment, and has the advantages of oxidation resistance, high and low temperature resistance, extreme pressure resistance, good lubrication and sealing performance and the like.