Composition I of UV curing adhesive

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Composition of UV curing adhesive (I)

uv curing adhesive is composed of basic resin, active monomer, photoinitiator, stabilizer, crosslinker, coupling agent and other additives. Under the irradiation of UV light with appropriate wavelength, the photoinitiator can quickly generate free agents or ions, and then initiate the polymerization and crosslinking of the basic resin and the active monomer to form a complex structure, so as to achieve the bonding of the bonding material

1.1 basic resin

1 The molding temperature should be strictly controlled not to exceed 350 ℃. 1.1 unsaturated polyester resin

unsaturated polyester resin is an earlier UV curing resin. It is composed of unsaturated dibasic acid (or acid mixed with partially saturated dibasic acid (or acid complex> reacts with diol under the action of initiator to make linear polyester. Unsaturated vinyl monomers exist in its molecular structure. If such unsaturated vinyl monomers are copolymerized with active vinyl monomers, they will be cross cured to form a body structure. The adhesive made from this resin has large volume shrinkage during curing, large internal stress in the bonding joint, and micro cracks are easy to occur in the adhesive layer Glue force becomes smaller; At the same time, due to the ester bond in the polymer chain, it is easy to be hydrolyzed in the presence of acid and alkali, so the medium resistance and water resistance are poor, and it is easy to deform in the environment of high temperature and humidity. In addition, its curing speed is slow, so its comprehensive performance is poor. Most of them are used as non structural adhesives. By reducing the content of unsaturated bonds, using monomers with small polymerization shrinkage, adding inorganic fillers and thermoplastic polymers, the overall performance of the polymer can be improved. Its advantage is low price, and it is still useful in wood decoration. On the other hand, due to the variety of synthetic raw materials, the resin can be made from hard to very soft. Only a few monomers can be added to obtain low viscosity and easy to operate. So far, its consumption in the European market still accounts for 24% of the total amount of UV curing resin

1.1.2 polyacrylic acid vinegar

it is prepared by condensation of alcohol and acid. By changing the types of polyols and polybasic acids and adjusting the molar ratio of polyols, polybasic acids and (meth) acrylic acid, adhesives with different properties can be prepared. The general formula for polyester acrylate synthesis is:

generally speaking, polyacrylic acid vinegar resin has low viscosity and good compatibility with other resins, but its curing shrinkage is high. Therefore, when used as a molded product, the size of the molded product is not very stable and is prone to distortion due to stress. It has been reported that this kind of adhesive has been used for DVD discs, and the adhesive performance is good

1.1.3 epoxy acrylic acid vinegar

it is obtained by the reaction of epoxy compound with (meth) acrylic acid or acrylic acid containing monooh. The commonly used epoxy compounds or epoxy resins include bisphenol A epoxy resin, hexahydrophthalic acid epoxy resin, aliphatic epoxy resin, etc. It is characterized by a monooh group at the P position of the acrylic group, so its viscosity is high. The molecules contain economic groups. Henan Kechuang aluminum based new materials Co., Ltd., which is independently established by Henan high efficiency aluminum based new materials innovation center, has carried out on-site acceptance of ether groups, ester groups and other polar groups, so that the resin molecules have a strong interaction with the adherend molecules, and the adhesion performance is excellent. It is superior to acrylate resin in electrical properties and heat resistance, and its molecular weight can be adjusted arbitrarily. Because of its strong adhesion and good light curing activity of epoxy resin, it is very popular and easy to corrode in outdoor environment. Bisphenol A epoxy resin acrylate cured product has high surface hardness, good chemical resistance, but large internal stress and brittle. In recent years, there are many reports on the improvement of its brittleness 1401. The epoxy acrylic resin modified with polyether end groups, which was obtained by toughening EA resin with polyether end groups, improved the toughness of the resin

1.1.4 polyurethane acrylate is prepared by the reaction of polyisocyanate, polyol and acrylic acid light group. Through the proper coordination of rigid polyisocyanate and flexible polyether segments, resins with different properties can be obtained. The product can be in a very hard state, an elastomer or even a very soft state. Polyurethane acrylate resin has the advantages of flexibility (especially low-temperature toughness), wear resistance, aging resistance and high tear strength of polyurethane vinegar, as well as good weather resistance and excellent optical properties of acrylic vinegar. The general reaction formula for synthesis is:

1.1.5 polymercaptan polyene system

the resin is actually composed of polymercaptan compounds and polyallyl compounds. Commonly used polysulfide compounds include the equivalence ratio of -sh of

or the number of functional groups in polyolefins and polysulfide molecules, which can obtain various forms of cured products from elastomers to resins. When polyene and mercaptan containing ester bond compounds such as esters generated by the reaction of polycarboxylic acid and allyl alcohol, esters generated by unsaturated carboxylic acid and polyols are used as the main components of thiol polyene system UV curing resin, the cured products are prone to hydrolysis under multi wet conditions, resulting in reduced bonding strength; while when Triallyl isocyanurate and

are used as UV curing components, soft, elastic A cured product with good transparency and moisture resistance. The system is not hindered by oxygen in the air, and the curing shrinkage is small. It is multi-purpose sub communication device, optical device assembly and optical fiber bonding


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