Novel, Fully Biobased Semicrystalline Polyamides

Abstract

Novel, semicrystalline polyamides and co(polyamides) were synthesized from biobased sebacic acid (SA), 2,5-diamino-2,5-dideoxy-1,4;3,6-dianhydroiditol (diaminoisoidide, DAII) as well as from 1,4-diaminobutane (DAB), also known as putrescine in nature. Low molecular weight polyamides were obtained by melt polycondensation of the salts based on these monomers or by interfacial polycondensation. In order to increase their molecular weights the polyamide prepolymers were submitted to a solid state polymerization (SSP) process. The chemical structure of the polymers was confirmed by 2D NMR correlation spectra (COSY), heteronuclear multiple-bond correlation spectra (HMBC) and by FT-IR spectroscopy. In the present work, FT-IR and X-ray techniques were used as a tool for the investigation of the crystal structure of the polymers after SSP. The X-ray diffractograms of the polyamides point to crystals containing both 4.10- and DAII.10-based repeat units. Because of the presence of diaminoisoidide residues the synthesized fully renewable products exhibit tunable polarities and melting points. Since most commercial polyamides have a much higher melting point than their end application requires, especially for fiber applications, this simple adaption can result in a significant reduction of energy consumption during processing.

Bio-polyamides based on renewable raw materials

“…The peak positions of the fitting procedure and the spacings as calculated by Bragg's law are reported in Table 3. Within the experimental inaccuracy, the spacings do not show any significant differences according to the literature for PAs [18,19,24,40]. The amorphous regions are reflected on the smectic peak at 2h between 18°and 20°and the amorphous halo at ca.…”

“…Jasińska et al [24] found similar results for polyamide 4.10 and its copolymers, and they described the peak at 2h = 23°as characteristic of the c-crystalline phase. On the contrary, for PA 6.6, Liu and coworkers assign this reflection as one of the distinctive features of the a-phase in polyamides and state that polyamides present usually more stable a-phase rather than c ones in XRD [20].…”

“…The N-H stretching mode appears as a single band at 3300 cm -1 , which indicates strong hydrogen bonding, and it is rather broad (Fig. 1), which may suggest that more types of hydrogen bonds with different bond lengths were formed [24]. Moreover, the shape (no shoulders) of the amide I (1637 cm -1 ) and II bands suggests also that some of the carbonyl groups are hydrogen bonded [25].…”

Recent Progress in Sustainable Polymers Obtained from Cyclic Terpenes: Synthesis, Properties, and Application Potential

“…In recent years, many different sustainable biobased polyamides have been described, for example, those derived from sebacic acid [89] or succinic acid, [90] which would give enough material for as eparate review.I n terms of terpene-based polyamides, it was shown some time ago that 6 could be transformed into its oxime and then into the corresponding lactam, which has been used for af ew homo-a nd copolymerization studies by ROP. [91,92] For homopolymers, intrinsic viscosity, IR absorption, and optical activity was determined for characterization, but no molecular weights could be given.L ater,i tw as shown that as econd regioisomeric lactam derived from 6 could also be isolated.…”

Reversible changes induced by temperature in the spherulitic birefringence of nylon 6 9

“…However, odd derivatives are gaining interest due to the development of materials based on renewable resources because of concerns over long-term availability of chemicals derived from fossil resources [1,2]. Nylons 5 6 [3-6], 6 9 [7] and 13 6 [8] can be considered in this context.…”