The Schiff base is not stable in acidic condition, alkaline condition is better. Tthe usually used pH range is 7~9.

It works at different pH with different rates. See

---Thermo- and pH-sensitive poly(vinylmethyl ether)/carboxymethylchitosan hydrogels crosslinked using electron beam irradiation or using glutaraldehyde as a crosslinker, Yan, Shifeng; Yin, Jingbo; Yu, Yang; et al., POLYMER INTERNATIONAL , 58 (11), 1246-1251 (2009).

Good luck

Glutaraldehyde works as a cross-linker for proteins and other aminogroup-containing polymers in weakly alkaline media, whereas cross-linking of hydroxylated polymers such as PVA requires for relatively strong acidic conditions with pH 1 or so, see for example: F. M. Plieva, M. Karlsson, M.-R. Aguilar, D. Gomez,

S. Mikhalovsky, I. Yu. Galaev and B. Mattiasson, Pore structure

of macroporous monolithic cryogels prepared from poly

(vinyl alcohol), J. Appl. Polym. Sci., 2006, 100(2), 1057–1066.

This is very similar to understand as HCHO. HCHO + phenol under acidic & basic conditions can be polymerized...like wise there are several publications on this issue....

Glutaraldehyde is much less reactive than formaldehyde and other aldehydes as a crosslinker. Here is an example in the attachment.

Alain

Glutaraldehyde may be used as an alternative to formaldehyde, in the tanning conversion of animal hides to leather. - as a less hazardous curing agent to be used in the workplace. Some evidence that varying the pH of reaction liquors, promotes differing interactions with amine, carboxylic or ionised carboxylic functions in the collagen's protein structure.