Wind turbine blades and other turbine components: core selection principle for the main load-bearing structure: Toughened epoxy for the main load-bearing structure; Polyurethane for dynamic joints / impact resistance; MS-modified silane for weather resistance and multi-material compatibility; Organic silicon for high and low temperature insulation sealing; Conductive epoxy / organic silicon sealant for electrical potting. For offshore wind power, additional indicators such as resistance to salt fog, hydrolysis, and electrochemical corrosion are required, and must comply with DNV/GL, IEC 61400-23, and NB/T 10653 wind power standards.
I. Wind turbine blades (maximum adhesive application area)
| Application site | Resin system | Core Performance Requirements | Recommended Plan | Key Usage Notes |
| Bonding of the primary structure comprising the blade main beam, skin, and web | Two-component toughened epoxy structural adhesive | High shear resistance, fatigue resistance, low shrinkage, and resistance todamp heat aging; adhesive layer thickness: 1–3 mm; large blades require low density and can be automatically pumped. | JOM1812 – Epoxy structural adhesive for wind power applications, JOME3002 | For the critical load-bearing adhesive, fatigue anddamp heat aging tests must be conducted; for the substrate materials (glass fiber / carbon fiber), the release cloth on the bonding surface shall be removed; for marine-grade applications, a hydrolysis-resistant composite formulation shall be employed… |
| Leaf root embedded bolt sleeve (metal–composite heterogeneous bonding) | Modified epoxy structural adhesive | High interfacial strength, low residual stress; adhesive layer thickness: 0.5–1 mm; creep-resistant and fatigue-resistant against pull-out failure | High-toughness epoxy AB adhesive; metal surface pretreatment via sandblasting and silane coupling agent application | The interface between metals and composite materials is highly prone to delamination, making surface treatment critical to its success. |
| Protection of the leading and trailing edges and the tip of the blade / Edge sealing | Single-component polyurethane (PU) sealant | High elongation, impact resistance, UV resistance, and suitability for blade vibration-induced deformation | PU elastic sealant | Due to high-speed vibrational impact on the absorption blades, rigid epoxy must not be used; otherwise, cracking may occur. |
| Vacuum infusion molding: temporary fixation of fiberglass cloth and guide mesh using spray adhesive | Synthetic rubber spray adhesive (low volatility) | Does not contaminate the epoxy matrix, features low VOC content, and does not compromise interlayer strength. | JOME3102 | Temporary positioning is applied only during the production process; it does not constitute structural bonding for 3M China. |
| Blade repair and localized defect repair | Repair epoxy (thixotropic) | Exhibits thixotropy without sagging; cures at room temperature or upon heating; possesses the same modulus as the matrix. | Two-component thixotropic epoxy repair adhesive | On-site operational and maintenance repairs may be performed using glass fiber short-cut filler. |
| Lightning protection system; copper mesh fixation and bonding | Epoxy / Low-modulus MS adhesive | Insulated, weather-resistant, and non-corrosive copper conductors | Modified epoxy resin or JOMS3360-modified silane adhesive | Avoid corrosion of metal lightning protection strips by common acidic silicones. |
Comparative Analysis of Adhesives (Quick Selection Guide)
| Resin type | merit | short slab | Applicable scenarios for wind power |
| Impact-Enhanced Epoxy Structural Adhesive JOME3211-146 | Features the highest strength, minimal shrinkage, and excellent chemical resistance, making it ideal for primary load-bearing applications. | Relatively hard, with limited fracture elongation and moderate low-temperature toughness. | Blade clamping, blade root bolt sleeve, mixing tower splicing, anchor bolt grouting |
| Polyurethane PU adhesive JOMP826 | Extremely high elasticity, impact resistance, excellent low-temperature performance, and salt spray resistance. | UV resistance is inferior to that of silicone; some PU materials are not paintable. | Blade leading edge, flange dynamic seal, gearbox seal |
| MS-modified silane adhesive JOMS3360 | No primer required, paintable, excellent weather resistance, low VOC, and no silicone migration. | Structural strength is lower than that of epoxy resin. | Cabin canopy, multi-substrate assembly sealing, lightning protection component fastening |
| Silicone sealant JOMS5339 | Extra-wide width, high temperature and UV resistance, hydrophobic and waterproof properties, and electrical insulation | The bonding strength is low, making it unsuitable for use as a structural load-bearing component; also, conventional silicone can leach siloxanes that contaminate electrical contacts. | Cabin high-temperature components, sensors, and cable seals (use with caution for electronic contacts) |
| MMA Methyl Acrylate JOM9103 | Rapid curing, excellent adhesion to metals and composite materials, and moisture resistance. | Strong odor; odor slightly weaker after prolonged exposure to damp-heat aging. | Rapid structural bonding and emergency repair of small components |
Distinguish load-carrying blade joints from protective seals
Adhesive selection for offshore wind turbine blades should separate the blade’s load-carrying joints from its protective and assembly functions. A bond between structural composite members transfers load, while an edge seal helps manage environmental exposure and a temporary positioning adhesive serves the manufacturing process. Good performance in one role does not establish suitability for another. Identify the joint geometry and the direction of loading before comparing materials. A long overlap can still experience opening forces at local transitions, particularly where the stiffness of adjacent sections changes. Review those regions rather than treating the entire bond as uniformly loaded. The structural adhesive material category is relevant to load transfer, with the composite surfaces and assembly method specified. Composite preparation deserves particular attention because the adhesive contacts the resin-rich surface, a prepared laminate face or another actual surface layer. Release residues, dust and unsuitable preparation can prevent useful adhesion even when the bulk adhesive cures normally. Removing a peel ply can be part of a controlled preparation route, but its suitability and the resulting surface still need verification for the intended bonding system. Avoid treating a visibly rough surface as proof that preparation is complete. In a mixed-material connection, such as a metal fitting bonded to a composite region, consider both surface interfaces and the movement between them. Cure history also matters in a substantial adhesive layer. A small open specimen may not reproduce the heat generation and heat removal of the actual joint. Why qualify a large bonded section using only a thin sample that never experiences the same curing conditions? It’s more useful to evaluate representative geometry and follow the selected formulation’s processing instructions. Review mixing, placement, supported gap and the time at which parts are closed and held. These process details should remain traceable to the inspected joint. A structural material comparison then addresses the real load path and interface, instead of relying on a generic assertion that a resin family is suitable for wind turbine blades.
Evaluate aged interfaces and retain the evidence needed for repair
Qualification of offshore wind turbine blades should consider how moisture and repeated loading reach the bonded interfaces. A cured surface that remains intact can conceal separation at a composite edge or around a metal fitting. Inspect representative joints after conditioning that reflects the intended temperature and moisture exposure, and evaluate their response to the relevant repeated loading. An initial static test is useful but does not answer every fatigue question. Salt exposure should be considered with the actual assembly materials and leakage routes in mind; resistance of an isolated specimen does not establish the condition of a wet interface beneath it. Protective seals deserve a separate inspection plan. The industrial adhesive sealant category can support discussion of weather-exposed joints, while the seal geometry must accommodate its intended movement and remain continuous through transitions. Edge protection and structural bonding should retain their separate design roles, even where they are close together on the blade. Observe whether an exposed edge opens, whether the protective layer cracks or whether moisture tracks along the interface. These outcomes require different remedies. When a structural specimen fails, record whether separation occurred in the adhesive, at an interface or within the composite. Damage to the laminate should not be described simply as poor adhesive strength. Cure defects and trapped air should also be distinguished from damage that appears only after conditioning. Use suitable inspection methods for the joint geometry and retain representative sectioned specimens where internal coverage needs investigation. For a repair, identify the condition of the remaining substrate and the process that can be achieved at the repair location. A surface prepared on a factory line may differ from an aged surface prepared in service. Existing coatings, moisture and access constraints can influence the repaired interface and its curing route. Keep the repair material’s function explicit, especially near fittings or electrical protection features that must retain their intended operation. Document surface preparation, material identity, curing conditions and the location of observed damage. That evidence supports a targeted repair assessment without assuming that a fresh laboratory bond proves the durability of an aged or repaired blade joint.
Selection of the right grade from the full JOME product catalogue usually starts with drawings and service conditions. The companion piece on Introduction to adhesive and lubricant solutions for sits alongside this guide, the JOME adhesive factory in Shanghai lists every family, and the reach the JOME technical staff handles enquiries.