L&L Products has launched Toughened T-Link, a fully amorphous thermoplastic adhesive designed to improve the ductility, flexural performance, energy absorption, and impact resistance of layered epoxy carbon-fiber composites.
The new material expands L&L Products’ existing T-Link platform while retaining characteristics intended to simplify composite manufacturing, including dry-to-the-touch handling, room-temperature storage and fast consolidation into composite structures.
Toughened T-Link is designed for applications that require high structural performance and damage tolerance. Potential markets include aerospace and sporting goods, where manufacturers frequently seek ways to reduce weight while maintaining strength and durability.
The material is engineered to conform to deep-drawn and irregularly shaped parts, giving manufacturers greater flexibility when integrating adhesives into complex composite geometries.
L&L Products is initially offering Toughened T-Link in pellet, micropellet and film formats, with converted yarn and filament formats currently under development.
The company said the technology was developed in response to a longstanding challenge involving layered epoxy carbon-fiber composites. While these structures can provide high strength and low weight, manufacturers may seek additional ductility and resistance to damage without sacrificing the processing advantages associated with thermoplastic adhesives.
Toughened T-Link is intended to address that requirement by increasing the ability of composite structures to absorb energy and withstand mechanical stress.
L&L Products reported encouraging results from internal testing.
Composite panels using Toughened T-Link film with epoxy prepreg layers demonstrated a considerable increase in short-beam shear performance under ASTM D2344 testing compared with panels produced using only epoxy prepreg layers.
More significantly, the Toughened T-Link panels demonstrated a 66% increase in compressive strength after impact under ASTM D7137 compared with panels containing epoxy prepreg layers alone.
Compression-after-impact performance is an important consideration for composite structures because damage caused by an impact may not always be readily visible while still affecting the material’s ability to carry structural loads.
Improving that performance could give manufacturers additional flexibility when designing composite components expected to operate in demanding environments.
The technology could also help manufacturers use material more selectively.
L&L Products said Toughened T-Link creates opportunities to use thinner films and monofilaments, potentially allowing adhesive to be placed specifically where it is required rather than across larger areas of a component.
That approach could help reduce unnecessary material and weight, an important consideration in applications such as aerospace where reducing mass can contribute to greater efficiency.
The thermoplastic properties of Toughened T-Link may provide additional lifecycle advantages.
Depending on the application and availability of appropriate services and processes, the material could support repairability, thermal debonding, reprocessing and recycling opportunities.
Thermal debonding could potentially allow bonded components to be separated through the application of heat, providing manufacturers with additional options for repair or end-of-life processing.
The introduction also reflects L&L Products’ broader focus on developing engineered materials for applications where structural performance, manufacturing efficiency and weight reduction are important.
The company works across automotive, aerospace, commercial vehicle and industrial markets, with capabilities spanning structural reinforcement, composite components, sealing, acoustics and vibration reduction.
With Toughened T-Link, L&L Products is extending those materials capabilities further into high-performance composite structures.
The product is particularly targeted at applications involving high flexural loads, where improved ductility and energy absorption could help engineers create lighter and more damage-tolerant designs.
As manufacturers increasingly use carbon-fiber composites to reduce weight while maintaining structural performance, materials that improve the behavior of layered composites following impact could become an important part of the overall system design.
Toughened T-Link is designed to provide that additional toughness without eliminating the handling and processing characteristics associated with L&L Products’ existing thermoplastic adhesive platform.
KEY QUOTES:
“Customers have been looking for a way to increase toughness and damage tolerance without giving up the processing advantages of thermoplastic adhesives. Toughened T-Link builds on our proven T-Link platform by delivering greater ductility, flexural performance, and energy absorption while conforming to complex composite geometries and deep-drawn parts. It also creates opportunities to use thinner films and monofilaments, helping manufacturers place adhesive only where it’s needed to reduce unnecessary weight and material.”
Don Paquet, Senior Scientist at L&L Products
