Chemical Structure and Properties of BDDA
1,4-Butanediol diacrylate (BDDA) is a bisacrylate produced by the reaction of 1,4-butanediol with acrylic acid. Its molecular structure contains a four-carbon alkyl chain with acrylate groups attached to each end of the chain.
The structure has the following importance:
Dual reactivity: the two acrylate groups can each participate in a free radical polymerization reaction, making BDDA an excellent cross-linker.
Short chain structure: The shorter chain length of BDDA results in a higher cross-link density than other diacrylates, resulting in a denser and more rigid polymer network.
Balanced Properties: BDDA’s structure allows it to provide excellent mechanical strength while ensuring chemical resistance for high performance UV/EB curing applications.
In the structure of BDDA: Butylene Glycol Core: A straight chain backbone consisting of four carbon atoms in a compact structure. Acrylate groups: Each end contains a vinyl group (-CH=CH₂) and a carbonyl group (C=O), a structure that allows for rapid polymerization under UV or EB light. Product Characteristics and Properties BDDA offers a number of excellent properties in UV/EB curing systems: High Crosslinking Density: Thanks to its two reactive acrylate groups and short alkyl chain, BDDA forms a high-density crosslinked network, resulting in excellent hardness, abrasion resistance and overall durability.
Fast Cure: The acrylate groups polymerize rapidly in the presence of UV light or electron beams, which is especially important in industrial environments where efficient production is required.
Low Viscosity: BDDAs typically have a low viscosity, which facilitates good wetting and uniform coating on the substrate.
Chemical Resistance: Cured polymers have high resistance to solvents, oils and other chemicals for a variety of industrial applications.
Enhanced Adhesion: High cross-linking density and fast curing properties combine to enhance the bonding properties of coatings and adhesives.Comparison of BDDA and HDDA PerformanceBDDA is often compared to 1,6-hexanediol diacrylate (HDDA) in UV/EB cured formulations.
Although they are both diacrylates, they differ in performance due to differences in molecular structure: chain length and flexibility: BDDA has a four-carbon chain, which results in a higher cross-linking density and a more rigid polymer network, while HDDA has a six-carbon chain, which has a lower relative cross-linking density and is usually characterized by better flexibility and impact resistance. Mechanical Properties: BDDA tends to provide higher hardness and abrasion resistance due to its high cross-linking density, making it suitable for applications requiring high durability.
HDDA is suitable for applications requiring a certain degree of flexibility and toughness. Application suitability: In automotive exterior coatings, industrial protective coatings and high-performance adhesives, BDDA is more advantageous due to its rigidity and abrasion resistance. In flexible packaging, lightweight materials and other fields, HDDA may be more suitable.
Areas of application BDDA is used in a wide range of UV/EB curing systems, including the following areas:
1. UV/EB curing coatings Automotive coatings: Used in automotive exterior protective coatings to provide scratch and weathering resistance and to ensure long term beauty of the body. Industrial Coatings: Forms a uniform, durable protective film on a wide range of substrates such as metals, plastics and wood, improving product durability and corrosion resistance.
2. Adhesives and Sealants High-performance Adhesives: Used as cross-linking agents in UV-curable adhesives to provide fast bonding and strong adhesion for electronics, automotive and industrial applications. Sealants: Used in the preparation of chemical and high temperature resistant sealants to protect critical components from environmental attack.
3. Printing inks UV-curable inks: used in packaging printing and digital printing to enhance ink curing speed, adhesion and abrasion resistance, thereby improving print quality and productivity.
4. 3D printing resins photosensitive resins: BDDA is used as a cross-linking agent in stereolithography (SLA) and digital light processing (DLP) 3D printing to provide high-resolution and high-mechanical strength printed parts.