LORD 7542C
Harmonization Code : 3919.10.80 | Other self-adhesive plastic rolls not exceeding 20 cm wide.
Main features
- 1:1 Medium-Work-Time Urethane Curative
- 10 to 20-Minute Working Time
- 60 to 120-Minute Handling Time
Product Description
LORD® 7542-C Urethane Adhesive Curative is Part 2 of the LORD 7542-A/C two-component structural urethane adhesive system. It must be combined 1:1 by volume with LORD 7542-A resin before use. LORD 7542-C is supplied as a tan liquid with a typical 4,000–14,000 cP viscosity at 25°C. When mixed with LORD 7542-A, the system provides a typical 11–15 minute working time at 24°C, approximately 2 hours to handling strength, and full strength in 24 hours or less.
Key features
- Curative component for the LORD 7542-A/C structural urethane adhesive system
- Equal-volume 1:1 mixing with LORD 7542-A resin
- Intermediate 11–15 minute working time for balanced assembly speed
- Suitable for cartridge or automatic meter/mix/dispense processing
- Supports FRP, SMC, CFRP, plastics, and prepared or coated metal bonding
- System-level typical tensile strength of 18.7 MPa with 70% elongation
- Documented system-level resistance to humidity, salt spray, water, and temperature exposure
Applications
- Composite panel and enclosure assembly requiring a medium working window
- Heavy-duty truck, service-truck, trailer, and vehicle-accessory bonding
- SMC, FRP, and CFRP structural joints
- Prepared or powder-coated metal-to-composite assemblies
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Thermal Properties
Additional Information
LORD® 7542-C Urethane Adhesive Curative
LORD 7542-C is Part 2 of 2 in the LORD 7542-A/C structural urethane adhesive system. It is not used alone. Combine it 1:1 by volume with LORD 7542-A resin to obtain an intermediate assembly window between the faster 7542-B and longer-work-time 7542-D systems.
.png)
Tan liquid curative for controlled equal-volume mixing
| Property | Typical value | Context |
|---|---|---|
| Component role | Curative, Part 2 of 2 | Must be combined with LORD 7542-A resin before use. |
| Appearance | Tan liquid | LORD 7542-C component. |
| Viscosity at 25°C | 4,000–14,000 cP | Component viscosity; not mixed-system viscosity. |
| Density | Published in DS3444 | Use the current controlled value for weight-ratio or consumption calculations. |
| Flash point | >93°C, closed cup | Does not eliminate decomposition, heated-process, or fire hazards. |
| Mix ratio | 1:1 by volume with LORD 7542-A resin | Use equal-volume cartridges or validated meter/mix equipment. |
Use only with LORD 7542-A resin at the documented 1:1 volumetric ratio
LORD 7542-A resin. LORD 7542-C is not a complete stand-alone adhesive.
11–15 minutes at 24°C using the supplier's 12.7 mm bead condition.
Approximately 2 hours at 24°C under the published test basis.
The mixed system reaches full strength in 24 hours or less at 24°C.
Prepare the substrates and combine 7542-C with 7542-A before the medium work window expires
- Remove grease, dirt, moisture, release agents, and other contaminants.
- For plastics, use a dry-rag wipe or a validated solvent-dampened rag.
- For metals, the TDS recommends priming or powder coating.
- Use equal-volume cartridges or automatic meter/mix/dispense equipment.
- Level cartridge plungers before attaching the mixer.
- Purge at least one mixer length before applying adhesive to the substrate.
- Mate parts within the 11–15 minute working time.
- Clamp until the mixed system reaches handling strength.
- Maintain a typical 254–1016 µm bondline for optimum adhesion.
.png)
Cure and final properties apply only after correct mixing with LORD 7542-A
Full system strength develops in 24 hours or less at 24°C.
Clean equipment and tools before cure with acetone or MEK. Do not use alcohol.
Heating the cured adhesive to approximately 149°C or above may soften it for separation; validate substrate heat resistance.
Painting and most cleaning processes are not expected to reduce bond strength under the supplier's system-level guidance.
Storage and industrial safety
LORD 7542-C is one of the curatives specifically excluded from the TDS warning about prolonged exposure below 10°C, but it should still be stored within the published 18–30°C shelf-life range in its original unopened container. A product-specific LORD 7542-C SDS was not supplied. Do not infer its hazard classification from the LORD 7542-B SDS. Obtain and review the current regional 7542-C SDS and package label before handling, and use the required ventilation, personal protection, storage, spill, transport, and disposal controls.
Do not assign final structural properties to LORD 7542-C curative by itself
LORD 7542-C is an uncured component. Final-state values apply only to a correctly metered, mixed, and cured LORD 7542-A/C adhesive system. DS3444 presents the bulk cured-property table at family level and does not explicitly identify the curative used.
| Property | Typical system-level value | Context |
|---|---|---|
| Hardness | 87 Shore A | ASTM D2240, Method A. |
| Tensile strength at break | 18.70 MPa | ASTM D638. |
| Elongation | 70% | ASTM D638. |
| Young’s modulus | 83.6 MPa | ASTM D638. |
| Glass-transition temperature | 46°C | ASTM D3418. |
| Moisture absorption | 1.65% | ASTM D570. |
Selected family-level room-temperature lap-shear results include 4.10 MPa on SMC, 17.90 MPa on e-coated steel, and 22.10 MPa on CFRP under the documented preparation, bondline, area, 1:1 mix, and 24-hour room-temperature cure. Confirm that these results apply to the A/C formulation before treating them as variant-specific.
Choose 7542-C where a balanced assembly window is more useful than the fastest or longest option
The LORD 7542-A/C system is positioned for SMC, FRP, CFRP, plastics, e-coated steel, powder-coated metals, truck and trailer structures, vehicle accessories, and other composite assemblies. Final qualification must address the 11–15 minute work window, equipment and mixer residence time, substrate and coating, bondline, joint geometry, clamping, peel, impact, fatigue, temperature, water and humidity exposure, painting, rework, and required failure mode.
LORD 7542-C selection, processing, and application guidance
Controlling technical data for LORD 7542-C curative, the required LORD 7542-A resin, process window, storage, system-level cured properties, and bond performance.
Open resourceFamily comparison covering LORD 7542 systems and curative-selection context.
Open resourceJoint design, substrate preparation, cartridge purging, bondline, fixturing, failure-mode, and rework guidance.
Open resourceGeneral structural-adhesive selection and market context.
Open resourceApplication context for service-body panels, compartments, roofs, and mixed-material structures.
Open resourceApplication context for utility and Class Eight trailer structures.
Open resourceValidate LORD® 7542-C with LORD 7542-A for your assembly window
Krayden can help review 1:1 package and equipment configuration, mixer choice, 11–15 minute work time, substrate preparation, bondline, clamping, storage, safety documentation, environmental durability, and final assembly qualification.
