Auxiliaries commonly used in Handern Seiko
DATE：2021/1/20 8:46:15 / READ： / SOURCE：This station
Auxiliaries commonly used in Handern Seiko
In order to improve the technological properties of the resin, the properties of the products after chemical reaction, and to reduce the cost, sometimes a variety of auxiliary agents are added to the local formula of the bonding agent. The common auxiliary agents are as follows.(1) Curing agent, initiator and accelerator epoxy resin are thermoplastic linear structure. Bigot uses curing agent to crosslink the moon type epoxy resin into a huge molecule with network structure, which becomes insoluble and insoluble curing product.
The curing of unsaturated polyesterane can be carried out by using initiator and curing under heating condition, or by using initiator and curing under accelerating temperature. Extrusion pre coating production line www.handern.com
(2) The viscosity of barrier release agent at room temperature is an important process parameter of resin binder. For example, the viscosity of the adhesive used in the hand gluing process is generally required to be less than 1 Pa.s (1000 CP). In order to reduce the viscosity of resin and meet the process requirements, a certain amount of diluent is often added to the resin. Diluents are generally divided into inactive diluents and reactive diluents. Inactive diluents do not take part in the curing reaction of resin. Generally, most of the non reactive diluents are removed by drying after impregnating resin. The commonly used inactive diluents are propanol, alcohol, toluene and benzene, and the dosage is generally 10 ~ 60% of the weight of resin. The viscosity of phenolic resin and epoxy resin is relatively high, so it is necessary to add inactive diluent to phenolic resin and epoxy resin.
Sometimes, volatile substances are not allowed to be added to the binder. In order to reduce the viscosity, we need to add a diluent. The active diluent takes part in the entrapment reaction of resin and becomes a part of network structure. The selection and dosage of active diluent are related to the structure of diluent and the type of tree eyebrow.
The addition of mono epoxy or multi epoxy low viscosity compounds can act as active diluents. The bacterial diluents of epoxy resin are shown in table 7-20. The amount of monoepoxy compound is generally 5-10% of the weight of the resin. The dosage should not be too much. The amount of polycyclic compound can be more than 10%. Epoxy resin active diluent is generally toxic, long-term contact will cause skin allergy, and even ulceration, which should be noted. Extrusion pre coating production line www.handern.com
(3) In order to reduce the applicability of the cured resin and improve the impact strength, the tougheners and plasticizers do not participate in the curing reaction, but only play an important role
Toughening agent and plasticizer. Commonly used plasticizers are phthalate esters, phosphate esters, etc. It is a kind of linear polymer, which has the function of toughening polyesters, reducing the rigidity of phenolic resin, and reducing the strength and heat resistance. Hospital of health. Polysulfide rubber is a kind of flexible group, which directly takes part in the curing reaction. For example, in the epoxy resin by adding polyacrylic adhesive; improve toughness. The fat is filled with butadiene rubber, etc. When the strength of the resin is not reduced by the agglomerating agent
(4) Thixotropic agent in the hand lay up process, in the paste of large products, especially in the vertical plane, often occurs resin sliding phenomenon, affecting the quality of products. In order to eliminate this drawback, the thixotropic agent of Yijing is often added to the resin. Thixotropic agent can improve the viscosity of binder at rest. Under the action of external force, such as stirring, it becomes a liquid liquid, so it is suitable for brushing large parts, especially in the vertical plane. The commonly used thixotropic agent is active silica (white carbon black), and the dosage is generally 1 ~ 3%. Thixotropic agent is usually added to the resin used in hand paste process. Extrusion pre coating production line www.handern.com
(5) Adding a certain amount of filler into the filler resin can improve its performance and reduce the cost. Adding a certain amount of filler to the resin can increase the viscosity of the resin, change its flow characteristics, reduce the shrinkage of the tree finger during curing and increase the surface hardness. The common fillers are porcelain clay, quartz powder, talc powder, mica, etc. Wet fillers should be dried before reuse. Some fillers will affect the cementation and curing rate of resin, which should be paid attention to. Sometimes, for some special purposes, some special fillers are added to the resin, such as adding molybdenum disulfide to improve the wear resistance; adding a certain amount of metal powder to improve its conductivity, etc.
(6) Pigment in order to make color composite products, a certain amount of pigment or dye must be added into the resin. The amount of pigment commonly used is 0.5 ~ 5% of resin. The pigment used should meet the following requirements: ① bright color, light resistance and heat resistance; ② good dispersion in the resin, not affecting the curing of the resin; ③ not affecting the performance of the product; ④ low price.
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