It is well-known that the properties of cross-linked rubbers are strongly affected by the cross-link density. In this work it is shown that for thermoreversibly cross-linked elastomers, the type and length of the cross-linker also have a significant effect. A homologous series of diamine and bismaleimide cross-linkers was used to cross-link maleic-anhydride-grafted EPM irreversibly and furan-modified EPM thermoreversibly, respectively. Bismaleimide cross-linkers with a polarity close to that of EPM and a relatively low melting point have a better solubility in the rubber matrix, which results in higher chemical conversion and, thus, higher cross-link densities at the same molar amount of cross-linker. Samples cross-linked with different spacers (aromatic and aliphatic spacers of different lengths) were compared at the same cross-link density to interpret the effects on the material properties. The rigid character of the short aliphatic and the aromatic cross-linkers accounts for the observed increase in hardness, Young´s modulus and tensile strength with respect to the longer, more flexible aliphatic cross-linkers. In conclusion, the structure of the cross-linking agent can be considered as an alternative variable in tuning the rubber properties, especially for thermoreversibly cross-linked rubber.

Microporous polymer frameworks have attracted considerable attentiont om ake novel separation layers owing to their highly porouss tructure, highp ermeability,a nd excellent molecular separation. Thiss tudy concernst he fabrication and properties of thin melamine-based microporous polymer networks with al ayer thickness of around 400 nm, supported on an a-alumina support and their potentialu se in organic solvent nanofiltration. The modifiedm embranes show excellent solventp urificationp erformances, such as n-heptane permeability as high as 9.2 Lm À2 h À1 bar À1 in combination with avery high rejection of approximately 99 %for organic dyes with molecular weighto f! 457 Da. These values are higher than for the majority of the state-of-the-artm embranes. The membranesf urther exhibit outstanding long-term operation stability.T his work significantly expands the possibilities of using ceramic membranes in organic solventn anofiltration.Supporting Information and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.