Crosslinking agent is divided into diplomatic linking agent and internal crosslinking agent.
1. Diplomatic agent
The so-called diplomatic linker is added before use, and then cross-linking reaction occurs under room temperature, heating or irradiation. Plus cross-linking agent is divided into the following categories: ⑴ polyisocyanate (JQ-1, JQ-1E, JQ-2E, JQ-3E, JQ-4, JQ-5, JQ-6, PAPI, emulsifiable MDI, tetraisocyanate). ⑵ Polyamines (propylene diamine, MOCA).
⑶ Polyols (polyethylene glycol, propylene glycol, trimethylol propane).
⑷ Glycidyl ether (polypropylene glycol glycidyl ether).
⑸ inorganic (zinc oxide, aluminum chloride, aluminum sulfate, sulfur, boric acid, borax, chromium nitrate).
⑹ Organic compounds (styrene, a-methylstyrene, acrylonitrile, acrylic acid, methacrylic acid, glyoxal, aziridine).
⑺ silicone (ethyl orthosilicate, methyl orthosilicate, trimethoxysilane).
⑻ benzenesulfonic acid (p-toluenesulfonic acid, p-toluenesulfonic chloride).
(1, 4-butanediol diacrylate, ethylene glycol dimethacrylate, TAC, butyl acrylate, HEA, HPA, HEMA, HPMA, MMA).
→ organic peroxide (peroxide 2, 2,4, dichlorobenzyl peroxide).
11 metal organic compounds (aluminum isopropyl alcohol, zinc acetate, titanium acetyl acetone).
(12) azolidine
How to set multifunctional polycarbide diimine cross-linking agent.
(14) sealing-type cross-linking agent
(15) Isocyanate crosslinking agents
2. Internal cross-linking agent
The so-called internal crosslinking agent means that it can be stably stored as a monomer into the chain of the macromolecular structure during polymerization, or added into the adhesive as a component, and only when heated to a certain temperature or radiation conditions can the crosslinking reaction occur. Commonly used internal cross-linking agents are olefins monomers, such as acrylic acid, hydroxyethyl acrylate, hydroxypropyl acrylate, methacrylic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, divinylbenzene, N-hydroxymethyl acrylamide, diacetone acrylamide.
Selection of crosslinking agent in different adhesives
For different adhesives, the appropriate cross-linking agent should be selected, and the cross-linking agent has the following requirements:
(1) The active group of the crosslinking agent can react with the components of the adhesive to form a crosslinking structure.
(2) With high crosslinking efficiency, stable crosslinking structure can be obtained only by adding a small amount.
(3) The crosslinking speed is suitable, too fast or too slow is not good.
(4) Mixed use of several crosslinking agents can obtain the best comprehensive effect.
The crosslinking agent is stable in the process and storage period, without harmful reaction and condensation. No toxicity, no irritation, no pollution of the environment.
8 Ratio of crosslinking agent
The editor
I. Epoxy resin can be crosslinked by cold-heat curing system based on acids, amines, amino resins, isocyanates, phenolic resins, etc.
Two, amino resin can be based on isocyanate, carboxylic acid or anhydride, epoxy resin, phenolic resin, etc., cold and heat curing system crosslinking;
Phenolic resin can be crosslinked by cold-heat curing system based on acid, epoxy resin and isocyanate, etc.
4. Alkyd resin can be crosslinked by cold-heat curing system based on acids, amines, amino resins, isocyanates, phenolic resins, peroxide, photoinitiator, etc.
Five, acrylic resin can be based on amines, amino resins, epoxy resins, isonitrile esters, phenolic resins, free radicals, cold and heat curing system crosslinking;
Vi. Polyethylene can be cross-linked based on peroxide, silanol, electron beam, etc.
Seven, conventional elastomers can be based on sulfur, peroxide, isonitrile ester, cold and heat curing system crosslinking;
Eight, special elastomers can be based on metal oxides, silanols, resins, amines, etc., cold and heat curing system crosslinking.
Classification of crosslinkers
Crosslinking agent is divided into diplomatic linking agent and internal crosslinking agent.
1. Diplomatic agent
The so-called diplomatic linker is added before use, and then cross-linking reaction occurs under room temperature, heating or irradiation. Plus cross-linking agent is divided into the following categories: ⑴ polyisocyanate (JQ-1, JQ-1E, JQ-2E, JQ-3E, JQ-4, JQ-5, JQ-6, PAPI, emulsifiable MDI, tetraisocyanate). ⑵ Polyamines (propylene diamine, MOCA).
⑶ Polyols (polyethylene glycol, propylene glycol, trimethylol propane).
⑷ Glycidyl ether (polypropylene glycol glycidyl ether).
⑸ inorganic (zinc oxide, aluminum chloride, aluminum sulfate, sulfur, boric acid, borax, chromium nitrate).
⑹ Organic compounds (styrene, a-methylstyrene, acrylonitrile, acrylic acid, methacrylic acid, glyoxal, aziridine).
⑺ silicone (ethyl orthosilicate, methyl orthosilicate, trimethoxysilane).
⑻ benzenesulfonic acid (p-toluenesulfonic acid, p-toluenesulfonic chloride).
(1, 4-butanediol diacrylate, ethylene glycol dimethacrylate, TAC, butyl acrylate, HEA, HPA, HEMA, HPMA, MMA).
→ organic peroxide (peroxide 2, 2,4, dichlorobenzyl peroxide).
11 metal organic compounds (aluminum isopropyl alcohol, zinc acetate, titanium acetyl acetone).
(12) azolidine
How to set multifunctional polycarbide diimine cross-linking agent.
(14) sealing-type cross-linking agent
(15) Isocyanate crosslinking agents
2. Internal cross-linking agent
The so-called internal crosslinking agent means that it can be stably stored as a monomer into the chain of the macromolecular structure during polymerization, or added into the adhesive as a component, and only when heated to a certain temperature or radiation conditions can the crosslinking reaction occur. Commonly used internal cross-linking agents are olefins monomers, such as acrylic acid, hydroxyethyl acrylate, hydroxypropyl acrylate, methacrylic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, divinylbenzene, N-hydroxymethyl acrylamide, diacetone acrylamide.
Selection of crosslinking agent in different adhesives
For different adhesives, the appropriate cross-linking agent should be selected, and the cross-linking agent has the following requirements:
(1) The active group of the crosslinking agent can react with the components of the adhesive to form a crosslinking structure.
(2) With high crosslinking efficiency, stable crosslinking structure can be obtained only by adding a small amount.
(3) The crosslinking speed is suitable, too fast or too slow is not good.
(4) Mixed use of several crosslinking agents can obtain the best comprehensive effect.
The crosslinking agent is stable in the process and storage period, without harmful reaction and condensation. No toxicity, no irritation, no pollution of the environment.
8 Ratio of crosslinking agent
The editor
I. Epoxy resin can be crosslinked by cold-heat curing system based on acids, amines, amino resins, isocyanates, phenolic resins, etc.
Two, amino resin can be based on isocyanate, carboxylic acid or anhydride, epoxy resin, phenolic resin, etc., cold and heat curing system crosslinking;
Phenolic resin can be crosslinked by cold-heat curing system based on acid, epoxy resin and isocyanate, etc.
4. Alkyd resin can be crosslinked by cold-heat curing system based on acids, amines, amino resins, isocyanates, phenolic resins, peroxide, photoinitiator, etc.
Five, acrylic resin can be based on amines, amino resins, epoxy resins, isonitrile esters, phenolic resins, free radicals, cold and heat curing system crosslinking;
Vi. Polyethylene can be cross-linked based on peroxide, silanol, electron beam, etc.
Seven, conventional elastomers can be based on sulfur, peroxide, isonitrile ester, cold and heat curing system crosslinking;
Eight, special elastomers can be based on metal oxides, silanols, resins, amines, etc., cold and heat curing system crosslinking.