Which adhesive should be avoided for rubber shock cords to ensure long-term performance?

Which adhesive should be avoided for rubber shock cords to ensure long-term performance?

• A. Slow-curing epoxy adhesives
• B. Cyanoacrylate glues (super glue)
• C. Aliphatic resin-based glues
• D. White "Elmer's" glue

Answer: (B)

Cyanoacrylate glues should be avoided on rubber shock cords because natural rubber needs to stay flexible, and CA glues cure into rigid bonds while also having chemical interactions with rubber that can embrittle the material. The rapid, hard bond created by cyanoacrylates doesn’t tolerate the repeated stretching and environmental changes a shock cord experiences, leading to cracks and bond failure over time. For long-term performance you want a rubber-friendly, flexible adhesive (or none at all, relying on proper knotting and construction). The other adhesives are less problematic for rubber in this context: some can provide a more flexible bond or avoid chemical attack, though they may not bond as strongly or durably as ideal for rubber under repeated use.

Cyanoacrylate glues should be avoided on rubber shock cords because natural rubber needs to stay flexible, and CA glues cure into rigid bonds while also having chemical interactions with rubber that can embrittle the material. The rapid, hard bond created by cyanoacrylates doesn’t tolerate the repeated stretching and environmental changes a shock cord experiences, leading to cracks and bond failure over time. For long-term performance you want a rubber-friendly, flexible adhesive (or none at all, relying on proper knotting and construction). The other adhesives are less problematic for rubber in this context: some can provide a more flexible bond or avoid chemical attack, though they may not bond as strongly or durably as ideal for rubber under repeated use.