Introduction to cationic light-curing monomers

1. Cationic photopolymerization mechanism

• Anaerobic polymerization resistance
• Less human irritation from epoxy monomer
• Less volume shrinkage

Better performance of polymerization product

Vinyl ether monomers

• • Classification of vinyl ether monomers

    

  • Vinyl ether-based monomers in market

    

  • Characteristics and applications of vinyl ether monomers

Characteristics:

•  Very low viscosity
• High dilution capacity
• Low toxicity
• Very fast reaction time (comparable to acrylate monomer)
• Single structure. The stability of the product formed with vinyl ether monomer curing agent alone is poor

Application: Used as a cationic light-curing reactive diluent, not used alone

Epoxy propane monomer

•       Classification of Epoxy propane monomer

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• Epoxy propane monomer in market

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• 2-(3,4-Epoxycyclohexyl)ethyltriethoxysilane CAS 10217-34-2

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• Bis[2-(3,4-epoxycyclohexyl)ethyl]tetramethyldisiloxane CAS 18724-32-8

•  Characteristics and applications of epoxy propane monomer

Characteristics for Glycidyl ether epoxy monomer

• Longer induction period for cationic light curing
• Low cationic light-curing activity
• Unsatisfactory performance of the product

Characteristics for Alicyclic epoxy monomers

• Lower viscosity
• Fast cationic light curing speed
• Excellent performance of the product
• Less variety of products, large differences in curing activity between products

Oxetane monomers

• Classification of Oxetane monomers

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•  Oxetane monomers supplied by our company

•  3-Ethyl-3-(hydroxymethyl)oxetane CAS 3047-32-3
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•  3,3′-(oxydimethanediyl)bis(3-ethyloxetane) CAS 18934-00-4
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• 3,3′-[(1-methylethylidene)bis(4,1-phenyleneoxymethyl)] CAS 105071-04-3
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•  3-Ethyl-3-(phenylmethoxymethyl)oxetane CAS 18933-99-8
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•  3-Ethyl-3-(phenoxymethyl)oxetane CAS 3897-65-2
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• 1,4-Bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene CAS 142627-97-2
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• 4,4′-Hydroxymethylbiphenyl polymer oxetane CAS 358365-48-7
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•  3-Ethyl-3-methacryloxymethyloxetane CAS 37674-57-0
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•  (3-Ethyl-3-oxetanyl)methyl acrylate CAS 41988-14-1
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• 3-Ethyl-3-[[3-(triethoxysilyl)propoxy]methyl]oxetane CAS 220520-33-2
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Characteristics and applications of oxetane-based monomers

Characteristics:

• Low curing volume shrinkage
• Low viscosity
• Low toxicity
• Fast reaction speed
• Ability to frontline polymerization and delayed curing
• Good performance of polymerization products

2. Influencing factors of cationic light curing

• Nucleophilic/basic substances
• The effect of temperature. During curing, the higher the temperature the faster the curing speed. (pre-baking, post-baking, self-produced heat)
• Effect of water/moisture. A small amount of water speeds up the curing process, and as the water content and humidity increase, cationic curing is inhibited.
• The effect of alcohol. Chain transfer agent that speeds up cationic light curing but reduces the molecular weight of the polymer.
• The effect of viscosity. The higher the viscosity of the formulation, the slower the reaction rate.