When I was doing a blend of two polymers, I determined from the literature that a cross-linking reaction with hydrogen bonding would occur between them.

Hydrogen bonding occurs when a hydrogen atom forms a covalent hydride with an atom of large electronegativity and small radius, which is almost protonated due to the strong shift of the shared electron pair between the atoms. This hydrogen atom can also have an electrostatic attraction with another atom that has a large electronegativity and contains a lone pair of electrons.

How do I determine which groups an amino group is hydrogen bonded to when it can be cross-linked with both hydroxyl and carboxyl groups?

When characterized by FTIR and XRD, a red shift of the peak of the group may occur when hydrogen bonding occurs, but I have found that this phenomenon is often not apparent in actual tests.

In X-ray diffraction (XRD) characterization, the occurrence of hydrogen bonding causes self-assembly, which increases the intensity of the diffraction peaks on the crystalline surface, but I have read in some of the literature that co-mingling also disrupts the crystalline structure, which reduces the intensity of the diffraction peaks。

I'm a little bit confused and would like to know specific information about how hydrogen bonding can be determined, thanks!