High-Performance Flexible Epoxy & Radiation-Curable Grades
Engineered for low internal cure shrinkage, superior crack isolation, impact dissipation, and high-tenacity crosslinking over metal, treated plastics, and inorganic substrates.
Overcoming Inherent Brittleness: Macromolecular Mechanics of Flexible Epoxy
Conventional bisphenol A diglycidyl ether (DGEBA) matrices deliver exceptional chemical resistance, high surface hardness, and rapid photopolymerization. However, their compact aromatic rigid backbone creates high crosslink density, resulting in extreme volumetric shrinkage, low peel resistance, and micro-cracking under mechanical cycling.
Aliphatic & Polyether Chain Spacers
By interspersing long-chain aliphatic polyether polyols into the oxirane backbone, our synthetic chemists increase molecular weight between crosslinks (Mc). This lowers the glass transition temperature (Tg) down to the -15°C to 25°C window, allowing the cured film to absorb mechanical vibration without catastrophic cohesive failure.
Dimer Fatty Acid Chain Extension
Utilizing C36 dimerized fatty acid moieties creates an internal plasticizing network. The extended hydrophobic carbon rings and aliphatic branches provide superior hydrolytic stability and chemical barrier performance while elevating elongation at break from <3% to over 60%.
CTBN / Liquid Rubber Adducts
Carboxyl-terminated butadiene-acrylonitrile (CTBN) adducts precipitate out during cure as discrete elastomeric nanodomains (50–200 nm). These phases trigger shear yielding and crack pinning, drastically enhancing Charpy notched impact strength and peel tenacity on metallic copper, aluminum, and sputtered plastics.
Epoxy Resin Polymer Performance Spectrum
Quantitative formulation guidelines contrasting unmodified epoxy acrylates, flexibilized epoxy hybrids, polyurethane acrylates, and specialty siloxane-modified matrices.
| Resin Chemistry Family | Tensile Strength (MPa) | Elongation at Break (%) | Tg (°C, DMA) | Volumetric Shrinkage (%) | Substrate Adhesion (Cross-Hatch) | Key Engineering Target |
|---|---|---|---|---|---|---|
| Standard Bisphenol A Epoxy Acrylate | 50 – 75 | 1 – 4% | 65 – 95 | 6.5 – 9.0% | 2B – 4B (Rigid Metals/Wood) | Hard Sanding Primers, OPV |
| Ever Ray Flexibilized Epoxy Acrylate (6160/6271) | 25 – 45 | 25 – 85% | -10 – 35 | 2.1 – 3.8% | 5B (PET, PI, PC, Metals) | FPC Coverlays, Impact Adhesives |
| Aliphatic Polyurethane Acrylate (Aliphatic PUA) | 15 – 35 | 80 – 250% | -25 – 20 | 1.8 – 2.9% | 4B – 5B (Plastics, Vinyl) | Non-Yellowing Outdoor & Wearables |
| Aromatic Polyurethane Acrylate (Aromatic PUA) | 30 – 55 | 40 – 120% | 10 – 45 | 3.0 – 4.5% | 4B – 5B (Engineered Composites) | High Abrasion Flooring, Tooling |
| Hyperbranched Reactive Acrylate | 60 – 90 | 1 – 3% | 90 – 130 | 4.0 – 5.5% | 3B – 4B (Glass, Metals) | Scratch-Resistant Hard Coats |
Formulator Tip: Managing the Viscosity-Dilution Trade-Off
Flexible epoxy backbones with extended polyether segments inherently display higher bulk viscosity (often 15,000–65,000 mPa.s at 25°C). To maintain optical clarity and surface wetting without causing plasticizer migration, Ever Ray recommends formulating with monofunctional and difunctional reactive diluents such as IBOA (Isobornyl Acrylate), ACM0 (Acryloyl Morpholine), and DPGDA (Dipropylene Glycol Diacrylate).
This retains an elongation ceiling above 50% while dropping processing viscosity to roll-coating or slot-die sprayable levels (<800 mPa.s at 25°C) without VOC addition.
Localized Applications: Solving Critical Interfacial Challenges
From flexible printed circuits to cryogenic aerospace potting, our flexible epoxy oligomers address complex thermal coefficient mismatches (CTE) and mechanical strains.
Flexible PCB & Wearable Display Potting
Flexible electronics demand repeated foldability (bending radius <1.0 mm) without micro-crack initiation or delamination from polyimide (PI) or rolled copper foils. Our dimer-acid modified grades offer exceptional dynamic flex endurance exceeding 100,000 MIT fold cycles.
EV Battery Modules & Power Electronics
Thermal management adhesives in lithium pouch battery packs and IGBT modules encounter aggressive thermal shock (-40°C to +125°C). Flexible epoxy networks isolate interfacial thermal expansion shear stresses, preventing premature bond failure between cooling plates and battery cells.
Aerospace & Wind Energy Composites
Brittle epoxy systems crack under cyclic aerodynamic loading. Incorporating CTBN-toughened flexible epoxy backbones as composite matrix additives increases GIC interlaminar fracture toughness by over 300%, suppressing delamination in thick carbon-fiber spar caps.
Optoelectronic & Lens Encapsulation
Micro-LED and CMOS image sensor packaging requires minimal cure shrinkage to prevent internal mechanical warping. Our low-stress flexible epoxy formulations yield refractive index stability (nD 1.50–1.53) and high transmission (>92%) across the visible spectrum.
Polymer Innovation: Advanced Curing & Green Synthesis Roadmap (2025–2030)
Meeting next-generation environmental standards and production line speeds with breakthrough macromolecular architectures.
Bio-Based Dimer & Terpene Backbones
Transitioning from fossil-derived petroleum epichlorohydrin and bisphenols toward bio-based succinic acid, cardanol, and dimer fatty acids. Achieving >45% renewable carbon content without compromising moisture barrier or high-temperature yellowing resistance.
Dual-Stage UV-Thermal Latent Polymerization
Combining free-radical acrylate photopolymerization for rapid 3-second pin-curing with latent thermal epoxy-anhydride/amine curing. Ideal for shadowed geometric recesses in complex automotive lidar, radar brackets, and multi-layer automotive electronics.
Cationic Cycloaliphatic Hybrid Networks
Pioneering cycloaliphatic flexible epoxy systems sensitized for long-wavelength UV-LED (365–395 nm). Completely unaffected by atmospheric oxygen inhibition, eliminating the need for nitrogen purging while keeping volume contraction below 1.5%.
Guangdong Ever Ray: Scale, Stability & Raw Material Security
Headquartered in Jiangmen with large-scale industrial chemical synthesis based in Dawan Industrial Park, Yunfu City. We deliver end-to-end quality assurance from base monomers to customized oligomer drums.
Integrated Monomer Sourcing
Direct supply contracts with premier domestic and international chemical petrochemical feedstocks guarantee that epoxy precursors, acrylates, isocyanates, and polyols maintain constant isomeric purity and minimal chloride trace levels.
DCS Automated Synthesis
10+ industrial stainless-steel and glass-lined reactor trains governed by DCS distributed digital automation. Critical end-points including acid value, hydroxyl value, and conversion rate are tightly managed within batch-to-batch standard deviations <1.5%.
Stringent QC Lab & Analytics
In-house GPC (Gel Permeation Chromatography) molecular weight distribution profiling, FTIR structural verification, rotational rheometry, and accelerated weathering chambers ensure each shipment matches export TDS specifications.
Global Market Regulatory Alignment & Local Technical Support
Our materials power Tier-1 and Tier-2 formulators across North America, the European Union, East Asia, and the ASEAN manufacturing belt.
REACH, RoHS 3 & TSCA Status
Full registration compliance under EU REACH regulations, non-SVHC declaration, RoHS 3 directive adherence (2015/863/EU), and low halogen profiles according to IEC 61249-2-21 standards for microelectronics encapsulation.
Export Logistics & Packaging
Flexible packaging options ranging from 20 kg sealed polycans, 200 kg steel/plastic drums, to 1,000 kg IBC totes. Light-barrier anti-static packaging and thermal logging options guarantee safe maritime transit without premature gelation.
Direct Formulator Support
Senior UV polymer chemists supply benchmark starter formulations, photoinitiator pairing advice (Type I vs Type II amine synergists), curing speed diagnostics, and substrate adhesion troubleshooting directly to your lab team.
High-Tenacity Acrylates & Specialty Adhesion Promoters
Browse additional synthesized grades optimized for extreme weatherability, scratch recovery, matte surface aesthetics, and plastic/metal bonding.
Technical Q&A: Flexible Epoxy Formulation & Manufacturing
Detailed insights compiled by our polymer synthesis research directors to answer common formulator and purchasing procurement queries.
