Rubber Bonding And Processes
Bonding agent: Also known as direct adhesive, chemical bonding or strong physical adsorption between the surfaces being bonded during vulcanization to form a firmly bonded substance.
Bonding: The process of adhering two surfaces of the same or dissimilar materials together to form an interface.
Adhesive: A substance that can bond adjacent surfaces of a material into one
Tackifier: A substance that increases the adhesion of a vulcanized adhesive
Binder: a substance that adheres discontinuous powder or fiber materials together to form a continuous whole
Adhesive: the substance that connects two or more productions together, mostly in the form of sticky tape, and achieves the purpose of bonding by spraying, pasting and other processes.
Bonding agent: added to the adhesive at the time of mixing, and at the time of vulcanization to make a chemical bond between the surfaces to be bonded into a strong substance adsorption, forming a strong bond
Impregnating adhesive: refers to the impregnating solution containing bonding components through the impregnation process to cover the substance in the fiber fabric.
Adhesion of rubber: the combination of rubber and homogeneous or heterogeneous material surfaces in contact with each other, produced by the action of van der Waals forces, hydrogen bonds, chemical bonding forces.
Adhesion of rubber: The force or work required to peel off two homogeneous films by pressing them together for a short time under a small load.
Phosphating: The process of placing steel parts in an acid phosphate solution to precipitate a crystalline phosphate film insoluble in water on the surface of the metal.
Phosphate film P ratio: defined as P / (P + H), so the level of P ratio indicates the phosphate film in the proportion of iron di-zinc phosphate rate of high or low.
Acid corrosion inhibitor: a polar molecule, selective in the active area of the metal surface in the form of adsorption of a protective film to prevent the acid and iron continue to react and achieve the purpose of corrosion inhibition.
Plasma: An electrically neutral ionized gas produced by electrochemical discharges, high-energy radiation, etc., of substances under the action of an external electric field.
Wetting: When the liquid and solid surface contact, the original gas-solid interface automatically replaced by the liquid-solid interface phenomenon.
1. Classification of adhesives: tackifiers, direct adhesives (bonding agents), bonding promoters, adhesives (the most widespread), and impregnating adhesives.
2. What are the varieties of cobalt salt accelerators: cobalt naphthenate, cobalt stearate, cobalt acetate, cobalt borate, cobalt decanoate. Mostly used for plating brass metal with sulfur-containing yellow glue. RFL impregnating solution is the most typical impregnating binder. r-resorcinol f-formaldehyde l-mastic.
3. the belt bundle ply, carcass, wire ring wire and carcass fiber cord in tires are related to bonding.
4. characterize the method of rubber bonding: static method (extraction method, peeling method), dynamic method (flexure method, dynamic extraction method)
5. technical methods of rubber bonding: adhesive adhesion method, adhesive method, dipping method, hard rubber method, brass plating method, direct bonding method.
6. mechanical engagement force is the main force of mechanical theory, intermolecular forces (mainly van der Waals forces) for the main role of adsorption theory.
7. In the dry situation when the rapid peeling easy to produce electrostatic gravitational force. Common bonding agents: methane-white system, triazine bonding ... , modified methacrylic ....
8. Weak interface layer at the bonding interface including: bubbles, dust, oil, precipitation of the binding agent, incomplete crystallization .......
9. bonding forces are mainly: ① chemical bonding forces ② intermolecular forces ③ electrostatic gravitational force ④ mechanical engagement force
10. bonding transition layer formed by the thermodynamic conditions: ① bonding surface between the wettability ② bonding surface between the mutual solubility
11. The way the bonding damage: interface, body, mixing. Butyl inner tube is usually used adhesive method and direct bonding method for bonding technology.
12. dissolving medium is different, rubber adhesives are divided into solvent-based and water-based. Fiber materials are divided into natural (cotton, linen and wool) and synthetic (nylon).
13. Rubber and fiber bonding the main bonding forces are: chemical bonding force, physical adsorption, mechanical engagement force. Bonding methods: fiber impregnation method (one-step impregnation method and two-step impregnation method), fiber coating method, direct bonding method.
14. One-step impregnation method RFL impregnating solution to add modifiers ① pretreatment isocyanate ② Rp resin.
15. The role of silica in the methane-white system: catalyze the generation of methane-bonded resin, delay the sulfur yellow sulfide reaction.
16. Commonly used metal surface treatment methods include: physical mechanical method, chemical treatment method. Physical machinery: ① turning process ② sandblasting ③ ultrasonic treatment ④ mechanical polishing Chemical treatment: ① acid washing ② alkali washing ③ oxidation reduction ④ phosphate treatment
17. phosphating solution components are divided into: ① zinc phosphating ② zinc calcium phosphating ③ iron phosphating ④ manganese phosphating ⑤ composite phosphating
18. Construction method classification: ① dipping phosphating ② spray phosphating ③ brush phosphating phosphating film quality points: heavy, secondary heavy, light, secondary light.
19. According to the reaction force of oil and alkali will be divided into oil: saponifiable oil (animal and vegetable oils and fats) and unsaponifiable (① mineral oil ② petroleum jelly).
20. Degreasing with cleaning materials: organic solvents, lye. Degreasing cleaning methods: mechanical agitation, scrubbing, spray washing, electrolytic cleaning.
21. Corrosion inhibitors are: aldehyde-amine condensate, thiourea and its derivatives, pyridine and its derivatives (the best effect).
22. Detect the thickness of the phosphate film on the surface of steel parts: visual method of appearance, microstructure microscopy method.
23. phosphate film corrosion resistance commonly used detection methods are: copper sulfate drip test method, immersion method.
24. Rubber and metal bonding methods are: hard adhesive method, adhesive method, brass plating method, direct adhesion method.
25. Factors affecting the adhesion of the rubber: rubber molecular structure, rubber formula, process conditions.
1. Factors affecting the bonding effect: ① internal factors: the nature of the surface to be bonded. ② external factors: humidity and temperature of the air; process factors: temperature pressure time. Take 2 questions: to reduce the surface energy tends to stabilize, so the solid surface will produce adsorption.
2. How does adsorption on a solid surface occur? A: The solid surface layer molecules are balanced by the surrounding force field and can only capture the gas phase from the surrounding medium, the
What is the effect of adsorption on bonding? A: ① conducive to bonding: to provide adsorption ② unfavorable: the surface is easy to contaminate, adsorption of dust, gas.
The impact of wetting on the bonding? A: The two surfaces are moistened with each other is a necessary condition for bonding, but not the only condition. Liquid in the solid surface wetting is conducive to bonding; liquid in the solid surface is not wet, not conducive to bonding.
3. What is the impact of the surface porosity of the material to be bonded? A: ① increase the surface area and surface energy, improve the adsorption ② harbor air, reduce the contact area, bonding decreased.
4. The influence of the fluidity of the adhesive material on the skeleton material bonding? A: good fluidity, conducive to the diffusion and penetration between the two surface molecules, increase the contact area, enhance the adsorption effect, conducive to bonding. Measures to improve the fluidity: ① through plastic refining, hot refining, mixing to reduce the Menny viscosity ② extend the scorching time of the rubber ③ increase the pressure
5. What is the effect of mutual diffusion between surface molecules on bonding? A: diffusion depends on the mobility of molecular chains and compatibility, generally low viscosity, good compatibility, high temperature, high pressure, long time, the degree of diffusion, the bonding force.
6. How the chemical reaction at the bonding interface? A: ① chemical reaction between the active groups on the two surfaces ② chemical reaction between the molecules on the two surfaces through coupling agents ③ active groups obtained through surface treatment.
7. Mechanical theory of bonding methods: ① surface mechanical grinding ② surface sandblasting treatment ③ surface etching ④ immersion glue ⑤ increase the bonding pressure.
8. adsorption theory of bonding methods: ① improve the surface polarity ② surface modification ③ reduce the surface viscosity ④ surface pressure ⑤ cleaning
9. unvulcanized rubber materials are easy to bond the reason? A: ① low surface energy, weak adsorption ② good molecular mobility, conducive to diffusion and penetration ③ good wettability between surfaces, good compatibility.
10. How to improve the viscosity of unvulcanized rubber? A: ① Add plasticizer in the rubber material to improve the fluidity ② Improve plasticity through plasticizing, mixing and hot refining ③ Apply glue on the adhesive surface ④ Prevent the rubber material from spraying frost to increase the adhesion.
11. Why polyester fiber, aramid fiber and rubber is difficult to bond? A: polyester fiber molecules contain ester groups, partially shielded by the benzene ring, the surface has a small amount of -OH, -COOH, the surface has hydrophobic; aramid fiber in the amide bond mostly directly with the aromatic group, which is shielded by the aromatic group to lose activity, and the surface is smooth.
12. What are the factors affecting the bonding effect of polyester fibers and rubber? A: ① fiber surface treatment quality ② rubber formula composition ③ process conditions ④ environmental factors. How to improve the bonding effect of rubber and polyester fiber? A: ① use unsaturated rubber, polar rubber ② long scorching time ③ appropriate addition of silica ④ join the bonding system.
13. What are the reasons for the appearance of rubber or white? A: ① rubber plasticity is low, poor fluidity ② rubber spray frost or scorch ③ rubber itself poor viscosity ④ calendering speed is too fast ⑤ cloth surface temperature is low ⑥ cloth surface is not clean.
14. rubber and metal bonding between possible and difficult: ① high surface energy, strong adsorption ② surface layer can not be intermixed with the rubber, diffusion ③ there is an oxide layer, the surface has polarity ④ easy to lose electrons, electrostatic adsorption
15. metal and rubber bonding before why surface treatment? A: ① to obtain a clean surface ② improve the surface energy ③ increase the surface roughness ④ to obtain the appropriate chemical activity
16. The role of phosphating: ① enhance the bonding with the workpiece ② improve corrosion resistance ③ improve decorative ④ improve wear resistance.
17. steel parts before phosphating why degreasing? A: The grease on the parts will prevent the formation of phosphate film, and after phosphating for painting will affect the bonding force of the coating, drying properties, decorative properties and corrosion resistance.
18. phosphate solution why add accelerator? A: It is to remove hydrogen, to prevent hydrogen is adsorbed on the metal surface and thus prevent the formation of phosphate film.
19. Hard rubber formulation features: ① hardness in 82-85 ② gel rate should not be too high ③ sulfur dosage of 30-40 parts.
20. The purpose of brass plating with zinc: ① regulate the speed of rubber and brass should ② stabilize the structure of the interfacial layer, the thickness of the plating layer is 0.2um.
21. P ratio of phosphate film corrosion resistance? A: P than the high phosphate film of its crystallization is not easy to lose water, but also not easy to absorb water, good corrosion resistance.