<p>I'm struggling with bed adhesion for nylon on a glass bed (122 °C measured) in an enclosed chamber (45 °C near the front, likely more on top of the print bed). I used a glue stick to enhance adhesion, but after around 20 minutes the print comes off the bed.</p>
<p>I tried a <a href="https://www.123-3d.nl/123inkt-lijmstift-medium-21-grams-i1326-t7445.html" rel="nofollow noreferrer">no-brand glue stick</a> and a <a href="https://www.123-3d.nl/Pritt-stick-medium-22-gram-i1329-t7445.html" rel="nofollow noreferrer">Pritt glue stick</a>.</p>
<p>Now I wonder whether they are suitable for the purpose, because nylon should really be printable in these conditions. Maybe the glue cannot hold those 100+ °C temperatures.</p>
<p>How to find out whether a glue stick is PVA-based and suitable for nylon (or polycarbonate, ABS) printing?</p>

Not all glue sticks work! The working ingredient of a glue stick is
Polyvinylpyrrolidone
; a more elaborate answer is found
here
on question:
"Why does hairspray work as an adhesive for ABS?"
.
There are very good alternatives to glue sticks and hair spray nowadays. Specific adhesion sprays exist for several years now (e.g. Dimafix, 3DLAC, Magigoo for PA, Plasticz, PrintaFix, Dr.Mat, etc.; my personal experience is with the first 2 mentioned, both work for nylon: Dimafix has more tack at higher temperatures > 80 °C, up to 80 °C 3DLAC works perfect).
E.g. Dimafix has a higher temperature application range than e.g. 3DLAC. From the
manufacturer
can be seen that:
Source:
http://www.dima3d.com/en/home/dimafix/
This image shows that the spray has its maximum tack/adhesion at about 120 °C and holds this adhesion level at least up to about 145 °C according to the image.
However, not all glues get stronger with temperature! PVA (also called PVAc) glues soften very quickly, making them good only at low temperature. See "
Influence of temperature on the strength of bonded joints
" which discloses this graph for PVAc Rhenocoll 3W, 4B Plus: