Bonding Nylon and PP with adhesives

[DanielGustafsson 0]

Hi! Is there someone out there who knows how to successfully bond two or more pieces of xstrand´s GF30-PP/PA6 with industrial adhesives? 

 

Thanks! 

 

[geert_2 557]

Recently I tried glueing PP-straps back together after cutting them. It were injection moulded parts, not printed.

 

You can bond them with cyanoacrylate, after roughening up the surface by sanding, and after using an "activator". These activators come in little tubes similar to a fluo pen marker with felt tip, except that the liquid is not ink but a chemical that partially dissolves the plastic (at least I think so, but I am not sure how it works chemically). Then apply the cyanoacrylate and *immediately* press parts together. The activator makes the bonding stronger and also speeds up curing, so you only have a few seconds before it is too hard.

 

I found these in a normal super market (such as Delhaize, Carrefour) and hardware shops (such as Brico, Hubo, and similar here in Belgium).

Bonding strength is comparable with older glues like contact glues and "universal glues". But it is *far less* than what we got used to today with cyanoacrylates and composite glues on good substrates. So under high loads and especially when peeling, it may fail. Depending on your application - if purely decorative, light loads or big surfaces - it can work.

 

Under high loads, I think you would be better off screwing, clamping (e.g. snap-fits or dovetails), or welding parts together.

 

An activator also improves bonding strength of PLA with cyanoacrylate, but the working time is reduced so much that it gets quite uncomfortable. You don't have time to align parts correctly anymore, they stick immediately. And if you are too slow, the glue is hard before even touching.