To increase adhesion to the Vectra LCP or similar materials, you have a few options:

1. Use an alcohol wipe with a 70:30 solution of IPA:water to clean the surface and put a uniform layer of -hydroxy groups onto the glass beads. As the glass ages, the humidity in the air deposits a buildup of hydroxyl units onto the surface. They are held in place by weak van der Waals forces. When an adhesive is placed on top, it is easy to remove these weak boundary layers. By removing them and starting fresh, you will achieve better adhesion.

2. Surface abrasion will increase the surface area and create a mechanical interlock, both yielding better adhesion to the substrate.

3. Dow Corning offers a few different primer systems, such as Dow Corning 1200. The primer can be applied by brush or spray. Allow the solvent to evaporate and then apply the adhesive to the bond line.

4. An air plasma treatment can also increase adhesion. Enercon and other companies offer gas or flame plasma treatment systems that can deposit bonding groups onto a substrate surface, enabling better chemical bonds to the surface.

5. Sometimes, a combination of some of the above options will have good results—in other words, surface abrasion with an alcohol wipe.