Synthesis and properties of poly(norbornene)s with lateral aramid groups

Abstract

This paper deals with the synthesis and investigation of comb-like poly(norbornene)s carrying lateral rod-like aramid groups. Two types of norbornene-based monomers were synthesized and copolymerized with a norbornene carrying an aliphatic side chain using ring opening metathesis polymerization (ROMP). The new monomers contain aramid derivatives that display different types of non-covalent interactions. The first monomer contains linear tri(p-benzamide)s, which exhibit the typical H-bonds that aramids are known for. The second monomer features tri(p-benzamide)s with bulky ethylhexyloxy side-chains, which suppress intermolecular hydrogen bonding and favor π–π-stacking. The monomers were copolymerized in various ratios and the influence of the composition on the material properties was investigated using Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA), and powder X-ray diffraction (XRD) experiments. The results show that the glass transition temperature increases proportionally with the concentration of the H-bonding monomer.