| Abstract: | According to trials with model compounds the annexed methylol amide groups in N-hydroxymethyl acryl amide polymers are linked with each other by ether and methylene bridges under elimination of water and formaldehyde. The proton catalysis favours methylene cross-linking. Part of the methylol groups escape the cross-linking reaction by reforming of carbonamide groups. The purely thermal condensation of the methylol ethers occurs by elimination of alcohol and leads to a cross-linking by N-substituted methylene-bis-carbonamide groups, while in the presence of protons alkyl formal additionally develops under formation of methylene bridges. |
