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Chemistry for sustainable building materials

Kategorie: ‘DADMAOH’

New publication
New crosslinkers for diallylammonium gels

February 8th, 2022 | by

N,N’-methylene bisacrylamide (BIS) is a very popular crosslinker for radical polymerisation in water. It is highly reactive but tends to undergo alkaline hydrolysis and suffers from low solubility. This study shows that BIS forms only inhomogeneous networks with slowly polymerising systems such as N,N-diallyldimethylammonium chloride (DADMAC). As a result, gels with very low cross-linking densities, i.e. high swelling capacities, disintegrate during the swelling test. Coherent, i.e. highly cross-linked gels are not accessible due to the solubility limit. A promising alternative are multivalent tetraallyl compounds, such as tetraallylammonium bromide, N,N,N‘,N’-tetraallylpiperazinium dibromide and N,N,N‘,N’-tetraallyltrimethylenedipiperidinedibromide. In contrast to BIS, the copolymerisation with DADMAC is statistic. However, gelation with the new tetraallyl crosslinkers is much slower than with BIS and follows the order TAPB < TAMPB < TAAB, but the differences become significantly smaller as the content increases. At low contents, all three enable the production of gels with high swelling capacities of up to 360 g/g.

T. B. Mrohs, O.Weichold
Multivalent Allylammonium-Based Cross-Linkers for the Synthesis of Homogeneous, Highly Swelling Diallyldimethylammonium Chloride Hydrogels
Gels 2022, 8, 100. https://doi.org/10.3390/gels8020100

New PhD Student

April 1st, 2020 | by

In April, we welcomed Tim Mrohs to the gels department. As part of his dissertation, he is researching hydrogels based on highly alkaline diallyldimethylammonium hydroxide (DADMAOH) for use in building preservation. He is focussing in particular on the development of alkali-stable crosslinkers and the formulation and investigation of molecular gel network structures. We wish him every success in his research and welcome him to the working group.

Completed Master Thesis

January 14th, 2020 | by

Congratulations to Tim Mrohs on successfully completing his master’s thesis in the field of alkaline hydrogels entitled ‘Synthesis of cross-linked copolymer electrolyte gels based on diallyldimethylammonium chloride and hydroxide’.