(1) coating field
Used in automobile: chassis primer, component paint, inner wall paint of tanker.
Used for containers: coatings on the inner and outer walls of food tanks, anticorrosive coatings on the inner and outer walls of storage tanks, and anticorrosive coatings on pressure tanks.
Used for factory equipment: anti-corrosion coating for equipment and pipelines, external coating for refrigerators and washing machines, and insulation coating for electrical equipment.
Used in civil engineering: anti-corrosion coatings for bridges, anti-corrosion coatings for steel structures, anti-seepage coatings for cement products, floor coatings, decorative coatings, functional coatings and steel mesh cement gates.
Used for ships: inner wall coating of bottom warehouse, marine container coating, steel corrosion protection coating.
Other applications: powder coating for steel furniture, powder coating for resistance elements, powder coating for steel parts, anti-corrosion and heavy-duty wear-resistant ceramics for valve bodies, shielded vertical pipeline pumps, solar water heaters, solar panels and weapons.
(2) the field of composite materials
Used in automobile: FRP automobile shell, FRP floor, FRP tanker, control system instrument and electrical parts, display, automobile dry ignition coil, FRP parts, anti-slip particle steering wheel cover, epoxy resin local reinforcement material,
Equipment used in the factory: glass fiber reinforced plastic oxygen cylinders, glass fiber reinforced plastic storage tanks, glass fiber reinforced plastic containers, pipes, molds, propellers, looms, aircraft honeycomb structural parts, engine covers, rollers, shafts, leveling of installation foundations, self-leveling floors, electromagnetic coils, pilot valves, glass parts, glass fiber reinforced plastic pump valves, electric carbon products, construction engineering structural parts and machine transmission parts.
Insulating materials: copper clad laminate, glass steel plate, tube, rod, transformer, relay, high voltage switch, insulator, transformer, impedance device, cable head, sealing or plastic sealing of electronic devices and components, alarm, solid power supply, FBT flyback transformer, focusing potentiometer, ignition coils of motorcycles, automobiles and other motor vehicles, electronic and electrical parts, light-emitting diodes, signal lamps and full sealing. Temperature transmitter, tape recorder head, circuit board seal, integrated circuit, diode and triode discrete devices, passive filter, LED structure package, packaged solar panel, power module, IC regulator and solid-state relay, coal mine safety detection system, intrinsically safe module and automatic recloser.
Used for sporting goods: FRP helmet, racket, golf club, fishing rod, bowling, sleigh, surfboard, FRP rowing boat, sailing boat, racing car, lounge chair and hockey stick.
Used in other fields: aircraft fuselage, helicopter spiral blades, wind turbine blades, medical instruments, surgical handles, cardiac pacemakers, handicrafts and jewelry, valve seals, water conservancy construction projects, electroluminescent screens, concrete wear-resistant layers, thermal insulation materials, animal models, spacecraft, ship stern shafts, rudder shafts, chemical wood, iron tower reinforcement, maglev train tracks, solar cell musical instruments, epoxy resin decorations.
(3) the field of adhesives
Application: room-temperature fast curing tough epoxy resin adhesive, conductive adhesive, room-temperature curing electrostatic flocking adhesive, optical structural adhesive, shuffleboard adhesive, chemical anchoring adhesive, high-function yarn, artificial flower, magnetic writing board, automobile maintenance adhesive, stone adhesive, etc.
⑷ Application of Toughened Epoxy Resin in Adhesive
The polymer alloy adhesive based on toughened epoxy resin and adding functional filler and curing agent overcomes its shortcomings such as brittleness, impact resistance and poor heat resistance. It has been widely used in machinery, electronics, electrical appliances, aerospace, aviation, coatings, bonding and other fields, and is known as the universal structural adhesive.
1, the choice of curing system
Curing agents of epoxy resin include amines and anhydrides. Amines are usually the main curing agents, anhydrides are generally used for electrical performance requirements, and imidazoles are used as accelerators.
Primary amines and secondary amines contain active hydrogen atoms, which are easy to undergo nucleophilic addition reaction with epoxy groups, thus crosslinking and curing epoxy resin. The curing process can be divided into three stages:
1) primary amine reacts with epoxy resin to generate macromolecules with secondary amine groups.
2) The secondary amine group reacts with another epoxy group to generate larger molecules containing tertiary amine groups.
3) The remaining amino groups and hydroxyl groups react with epoxy groups.
The acid anhydride is ring-opened under the action of hydroxyl group of epoxy resin, trace water and hydroxyl-containing compounds, and the generated carboxyl group is added with epoxy group to obtain ester group. The hydroxyl group generated by esterification reaction and the hydroxyl group of epoxy resin catalyze the ring opening of epoxy resin to generate etherification reaction at high temperature, and the ring opening, esterification and etherification are repeated until the epoxy resin is crosslinked and cured, which is the curing mechanism of anhydride.
Imidazole is a five-membered ring containing two nitrogen atoms, one nitrogen atom constitutes a secondary amine and the other nitrogen atom constitutes a tertiary amine, which can be used as both a curing agent for epoxy resin and an accelerator for curing epoxy resin. Epoxy resin can be cured at medium temperature, but its heat resistance and mechanical properties are excellent, which is equivalent to aromatic amine curing agent, but its medium resistance and wet heat aging resistance are slightly poor.
The molecule of imidazole curing agent contains secondary amine group and tertiary amine group. The curing of epoxy resin can be divided into two steps. Firstly, the active hydrogen on the secondary amine is added to the epoxy group, and then the tertiary amine catalyzes the homopolymerization of the epoxy resin. The curing reaction has two exothermic peaks, which are 60℃ and 1 1 10℃ respectively. A small amount of aromatic amine can be added to improve its resistance to damp-heat aging.
2. Study on filler selection
The heat resistance of adhesive is not only related to the types, varieties and molecular structures of basic polymers, curing crosslinking agents and other components in the system, but also closely related to the heat-resistant fillers selected in the system. Proper introduction of heat-resistant filler in the formula will often obviously improve the heat-resistant performance of the system.
Commonly used heat-resistant fillers include surface-modified fumed silica, surface-treated zinc oxide, iron oxide and alumina. After surface treatment, the heat resistance of fillers can be obviously improved, such as silicone rubber system with (MeSi)2NH treated silica as filler. Even after 48 hours at 250℃, its tensile strength is 9.3Mpa, and its elongation is 335%, if the same kind of silica without surface treatment is used.
The same silicone rubber system as the filler. After thermal aging under the same conditions, the tensile strength and elongation are 6.6Mpa and 228% respectively. Visible. Heat-resistant filler can significantly improve the heat resistance of silicone rubber.
All kinds of carbon black, nano calcium carbonate, titanium dioxide, etc. It has the functions of strengthening, improving various physical properties, thickening, reducing cost and coloring. Fillers can reduce the shrinkage of products. Reduce internal stress. It is of great significance to improve the comprehensive performance. For example, quartz powder can improve the hardness of the adhesive layer and the fluidity of the potting adhesive; Silicon micropowder can improve the bonding strength, but the storage period will be shortened: adding a small amount of zinc chromate can improve the wet heat resistance and salt spray resistance; Adding 325 mesh glass flake has excellent corrosion resistance and water resistance; Adding calcium sulfate whisker has obvious toughening and strengthening effects, improving heat resistance and boiling water resistance. Flame retardant and antimony trioxide improve oxygen index and antioxidant 264, and prolong the service life of cured products.
3, polymer alloy repair materials
Berzona Molecular Company was founded in 1952. It is the first multinational organization dedicated to the research, development and production of polymer repair materials to solve the problems of corrosion, wear and aging of industrial equipment. The polymer alloy repair agent produced by Berzona Molecular Company was first applied to the repair of chemical equipment after corrosion. Germany's TipTop company has always been in a leading position in the field of belt maintenance and application, and is the world's largest manufacturer of hot and cold vulcanized rubber materials. Its products include: cold vulcanization bonding materials and hot vulcanization bonding materials needed for rubber bonding, PvC adhesives, roller coating materials and tools, conveyor belt repair materials, etc. Other companies, such as Devcon and e-wood, have similar products, which refer to composite adhesive materials (or repairing agents or adhesives) composed of high molecular polymers and special functional fillers (such as graphite, molybdenum disulfide, metal powder, ceramic powder and fiber). The new material can achieve high adhesion, excellent corrosion resistance, wear resistance and high compressive strength, and also has good sealing, moisture resistance and insulation. Therefore, it is widely used in the field of equipment maintenance in machinery, construction, electronics, light industry, petroleum, chemical industry, shipbuilding, aviation and other industrial sectors. On the one hand, it can be directly used as a new connection mode besides riveting, welding and threaded connection. On the other hand, any equipment may be worn, damaged, scratched, corroded, eroded, out of size, casting defects and so on. Repair in the shortest time. Polymer alloy repairing agent, also known as "cold welding" or "doctor of industry", can repair all kinds of cracks, scratches, size deviation, casting defects and so on. It can also be used as a size recovery and pre-protection coating for parts wear and corrosion.
The polymer of polymer alloy is mainly made of toughened epoxy resin, and other materials such as modified acrylate and polyurethane can also be used as bonding materials, and the above polymers can also be modified to give new characteristics to the materials. And adding fillers with different functions. So as to endow the material with the functions of electrical conductivity, thermal conductivity, magnetic permeability, temperature resistance, heat insulation and the like, and the parts have no heat affected zone and deformation, so that the material is convenient to use and can be used without heating or pressurizing. Normal temperature operation, no need for special equipment, quick and simple repair, field operation, versatility, wear resistance, friction reduction, corrosion resistance, rapid curing, wet surface repair, high and low temperature resistance and high strength. Various repairing agents such as conductive, insulating and potting are suitable for repairing materials such as metal, rubber, ceramics and concrete. Users can flexibly select the corresponding products according to equipment material, working temperature, pressure, chemical medium, downtime, site environment and other factors. Widely used in marine shaft, pump and pipeline equipment, it has the characteristics of simple operation, reliable performance and shortened docking repair cycle.
The main applications are as follows:
1) ship main engine and auxiliary engine repair;
2) Repair and sealing of heat exchanger and heating pipe in oil bin;
3) Repair, regeneration, anti-corrosion and wear-resistant treatment of tail shaft, rudder pin and rudder pin seat hole;
4) Repair and regeneration of propeller blades and cavitation resistance;
5) Anti-corrosion of deck and storage tank.
4. Modified epoxy structural adhesive
1) structural adhesive for steel plate reinforcement. Reinforcing glue, anchoring glue, fiber reinforced glue
2) Structural adhesive film for aerospace. Paste. Room temperature curing and heating curing
4) Other industrial adhesives are resistant to environment, high and low temperature, vibration and aging. V. References (omitted)