Permabond 2050 cyanoacrylate thick gel, high viscosity, gap filling (Instant Adhesive)

PERMABOND® 2050 is a flexible cyanoacrylate adhesive, exhibiting improved peel strengths when compared to other grades. It has excellent impact and vibration resistance, and is suitable for bonding dissimilar materials which could be subject to thermal shock or thermal cycling. 2050 is ideal for use on flexible or semiporous surfaces. 

And can even bond thse difficult surfaces if the POP primer is applied first to the difficult surface side. (POP means Polyolefin Primer):

• POolypropylenes (PP, PPCO, PPHO),
• Polyethylenes (HDPE, MDPE, LDPE, LLDPE, UHMW, PE)
• Silicone sheets or surfaces, prime first with
• PTFEs aka Teflons