1,6-Hexanediol diacrylate (HDDA): UV-curable coatings – driven by both policies and technology
Thread Content
1,6-Hexanediol diacrylate is a bifunctional reactive diluent for UV-curing systems, featuring low viscosity, high reactivity, and a balance between rigidity and flexibility; it is a key material in fields such as coatings, inks, adhesives, and 3D printing. It should be noted that HDDA and 1,6-hexanediol (HDO) are in a upstream-downstream relationship: HDO is a basic chemical raw material belonging to the category of saturated diols, while HDDA is its acrylate derivative and a functional monomer specifically used for UV curing. HDO serves as the key raw material for HDDA, and the two differ significantly in terms of product properties and application areas. I. Definition: HDDA is a colorless and transparent liquid. Its linear bifunctional structure – with acrylate groups at both ends that confer high reactivity – and the six-carbon chain in the middle provide excellent flexibility. Specifically, this is manifested as follows: 1. Low viscosity and high reactivity: At 25°C, its viscosity is only 5–10 cps, which allows it to significantly improve the fluidity of the system when used as a reactive diluent; it can also rapidly form a three-dimensional cross-linked network under UV light. 2. Excellent comprehensive performance: Its glass transition temperature is around 41°C, and the cured film possesses both hardness and impact resistance, in addition to good chemical resistance, hydrolysis resistance, and weather resistance. 3. Environmental benefits: It can replace traditional solvent-based thinners, resulting in extremely low VOC emissions. Its curing time is just a few seconds, and its overall energy efficiency is much higher than that of traditional thermal curing processes; it is therefore a key material for green manufacturing. II. Production Process 1. Currently, the industrial production of HDDA primarily relies on the direct esterification method, which involves reacting 1,6-hexanediol with acrylic acid in the presence of catalysts and polymerization inhibitors. This process features fast reaction rates and high yields. 2. Traditional process: Sulfuric acid or p-toluenesulfonic acid is commonly used as a catalyst, while hydroquinone and phenothiazine are used as polymerization inhibitors. This process is complex, generates large amounts of waste alkaline solution during post-treatment, causes severe corrosion to equipment, and the polymerization inhibitor may affect the appearance of the product. 3. Technical optimization: Hydrogen-type strongly acidic macroporous cation exchange resin is used as a catalyst, offering advantages such as easy separation and recovery after the reaction, reusability, and no corrosion to equipment. A new type of composite inhibitor system composed of inorganic substances such as sodium bicarbonate and copper sulfate is used to enhance the inhibition effect, facilitate post-treatment, and improve the product’s appearance. III. Sources of Technology and Progress in Localization 1. Internationally Leading Companies: The global market has long been dominated by international companies such as Sartomer, Evonik, and BASF, which hold advantages in high-purity products, specialty derivatives, and bio-based technologies. 2. Domestic situation: China has become an important production and consumption market for HDDA worldwide. According to industry reports, the market size for HDDAs in China is expected to reach 1.25 billion yuan by 2025, with a compound annual growth rate (CAGR) of around 8.7%. The East China region is the core production base, accounting for over 60% of the country’s total production capacity. Domestic companies such as Zhejiang Longsheng and Jiangsu Sanmu are gradually enhancing their competitiveness in the high-end product sector through technological upgrades. 3. Domestic substitution: Self-sufficiency has been achieved for ordinary-grade HDDA. However, in the area of high-end products such as electronic-grade HDDA, ultra-high-purity HDDA (with a monomer content of less than 200 ppm), and bio-based HDDA, there is still a gap between domestic technology and international advanced levels; demand for these products relies on imports, leaving ample room for domestic substitution.
IV. Application Scenarios 1. Traditional areas of advantage: (1) UV coatings and inks: HDDA is used as a reactive diluent to adjust the viscosity of the system and improve adhesion to substrates such as plastics and metals. Under environmental protection policies, the use of UV coatings in the automotive, electronics, and packaging industries is continuing to increase. (2) Adhesives and sealants: Free radical polymerization enables the formation of a high-strength cross-linked structure, granting the adhesives excellent shear strength and a wide temperature tolerance range. (3) 3D printing materials: When combined with photoinitiators, they are used in photopolymerizable 3D printing resins, enhancing printing accuracy and interlayer adhesion; they are widely applied in fields such as dentistry and industrial prototype manufacturing. 2. Emerging frontier fields: (1) New energy materials: Used as comonomers in the synthesis of polymer electrolytes, they can improve the conductivity and cycle life of lithium-ion batteries. (3) Biomedical engineering: Microspheres for drug sustained-release systems can be prepared through suspension polymerization, enabling the continuous and controlled release of drugs. (3) Other fields: It is also used in areas such as textile printing, plastic modification, and as a flotation collector (in mineral processing). V. Analysis of Market Structure, Production Capacity, and Profits 1. Production Capacity and Supply and Demand: By 2025, the total production capacity of China’s HDDA industry will reach 280,000 tons per year, with actual output around 210,000 tons. Ordinary-grade products are in ample supply, while there remains a shortage of electronic-grade ultra-high-purity and specialized HDDA products. 2. Market competition: Leading companies hold approximately 70% of the market share. International giants and domestic leading companies jointly dominate the market. Domestic enterprises enhance the competitiveness of their industrial chains by producing high-value-added derivatives such as HDDA and HEDA. 3. Profit level: High-end products enjoy higher gross profit margins due to high technical barriers and strict certifications. The profit margin for ordinary-grade products is relatively narrow. Companies with the advantage of an integrated industrial chain can achieve more stable and substantial profits by controlling raw material costs. VI. Industry Development Trends 1. Environmental protection drive: Strict environmental regulations worldwide and in China (such as those regarding VOC control and the dual-carbon goals) will continue to push solvent-based coatings and inks toward UV-curing systems, thereby creating a long-term and stable growing market for HDDA. 2. High-end products: The upgrading of downstream industries imposes higher requirements on indicators such as the purity of HDDA, the content of residual monomers, and color, prompting companies to move towards producing products with ultra-high purity levels suitable for electronic and pharmaceutical applications. 3. Green manufacturing: The research, development, and industrialization of bio-based HDDA represent an important direction, as it utilizes renewable raw materials and is in line with the trends toward sustainable development. 4. Intelligent production: The application of intelligent manufacturing and digital production technologies helps improve product consistency and production efficiency, while reducing energy consumption. 5. Diverse demands: In addition to its traditional applications in the markets for conventional UV coatings and inks, HDDA is seeing accelerated use in emerging fields such as new energy vehicles (lightweight materials, interior adhesives), 5G communications (electronic packaging adhesives), high-end equipment manufacturing (3D printing), and new energy batteries, thereby opening up new avenues for growth. For domestic enterprises, only by continuously increasing investment in research and development, overcoming key technologies such as ultra-high purity purification and bio-based synthesis, and closely aligning with the needs of downstream applications can they gain a competitive advantage in the industry and seize this wave of development opportunities driven by policies and technology
【History of Haichuan Chemicals】The defunct chemical plant – Yongji Shanxi Pesticide Factory https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718549 (Source: Haichuan Chemicals Forum (Hua Haichuan Liu hcbbs))
【Special Equipment Safety Management and Standardization】Summary Post! Constantly being updated – feel free to communicate! ! ! https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718553 (Source: Haichuan Chemical Industry Forum (Hua Haichuan Liu hcbbs))
【Ten Years of Rapid Development in Chemical Equipment】3082-2026 to Fill the Gaps. The first-phase project of Zhonghua Chemical Western New Materials, with a production capacity of 50,000 tons per year for ultra-high molecular weight polyethylene, successfully completed its trial operation upon initial feeding. https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5717659 (Source: Haichuan Chemical Forum (Hua Haichuan Liu hcbbs))
[Common Issues in Haichuan Pipeline Design] -- What are the hazards of not installing a check valve at the pump outlet? https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718575 (Source: Haichuan Chemical Industry Forum (Hua Haichuan Liu hcbbs))
【Ten Years of Rapid Development in Chemical Processing Equipment】100% domestic production of key core equipment from 2038 to 2026; Asia’s first salt cavern hydrogen storage project comes online https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718499 (Source: Haichuan Chemical Industry Forum (HCBBS))
【Ten Years of Rapid Development in Chemical Engineering Equipment】Successful testing of China’s first 90MPa motor-driven high-pressure liquid hydrogen pump, independently developed by Hangyang, from 3099 to 2026: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718510 (Source: Haichuan Chemical Industry Forum (HCBBS))
【Ten Years of Rapid Development in Chemical Engineering Equipment】China’s first set of 40-megapascal high-pressure centrifugal compressors for gas storage facilities was put into operation in 3100–2026. https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718636 (Source: Haichuan Chemical Industry Forum (HCBBS))
【HaiChuan Safety Discussion】Hidden Dangers Around Us – Failure to Inspect the Breathing Valves of Atmospheric Pressure Storage Tanks https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718677 (Source: HaiChuan Chemical Forum (HuaHaiChuanLiu hcbbs))
[3D Process Flow] Compilation post -- Petroleum refining process flow diagram 17 – Schematic diagram of the desulfurization process using copper-13X molecular sieves https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5718698 (Source: Haichuan Chemical Engineering Forum (HCBBS))