Biobased Semiaromatic Polyamides Derived from Dimethyl Furan-2,5-Dicarboxylate: Influence of the Composition on Their Properties

Abstract

Aiming at biobased semiaromatic polyamides with high performance from furan derivatives and studying the effect of the ratio of furan rings to benzene rings on the properties of polyamide, a series of poly­(decamethylene terephthalamide/decamethylene 2,5-furandicarboxamide) copolyamides (PA10T/10Fs) with the furan ring content ranging from 0 to 100 mol % were prepared from 2,5-furandicarboxylic acid derivatives, terephthalic acid, and 1,10-decanediamine via a two-step polymerization method. Their molecular weight, intrinsic viscosity, composition, and chemical structure were determined using an Ubbelohde viscometer, gel permeation chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance. The properties of PA10T/10Fs were characterized by X-ray diffraction, differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis, thermal deformation temperature measurement, heat deflection temperature measurement, tensile measurement, notched impact test, and water absorption measurements. The results showed that the target products had been successfully prepared, the PA10T/10Fs with a 10F content of no more than 20 mol % were crystalline, and these copolyamides exhibited comparable heat resistance and elevated tensile strength and elongation at break with those of the PA10T homopolymer. With the further increase of the 10F content, PA10T/10Fs turned amorphous gradually, together with improved transparency, indicating that the intermolecular hydrogen bond was effectively suppressed, which was also supported by density functional theory (DFT) calculations, and the heat resistance and tensile strength decreased slightly, but the elongation at break increased; moreover, the increased furan ring content in PA10T/10Fs resulted in a lower notched impact strength and increased water absorption.

Effect of copolymerization on the thermal characteristics and behavior of crystallization of biobased semi‐aromatic PA10T/10I

“…It was clear from comparing these five images that pure PA10T had relatively large crystalline grains 33 . Whereas for PA10T/10I, a dense granular texture of crystals was formed, IPA increased the number of crystal nuclei, and the size of crystalline grains decreased as IPA content increased 34 . Meanwhile, a similar result has been reported by Tong et al, and they synthesized a series of novel thermoplastic elastomers based on PA10T/10I with different sizes of the crystals 17 .…”

“…33 Whereas for PA10T/ 10I, a dense granular texture of crystals was formed, IPA increased the number of crystal nuclei, and the size of crystalline grains decreased as IPA content increased. 34 Meanwhile, a similar result has been reported by Tong et al, and they synthesized a series of novel thermoplastic elastomers based on PA10T/10I with different sizes of the crystals. 17 Moreover, it was harder to find a typical spherulitic structure due to the weak crystallization capacity of copolyimide PA10T/10I.…”

PEGylated Amphiphilic Gd-DOTA Backboned-Bound Branched Polymers as Magnetic Resonance Imaging Contrast Agents

“…1 H NMR spectra were first studied to evaluate the structure of non-PEGylated (P­(DOTA-C 6 ) and P­(DOTA-C 10 )) and PEGylated [(mPEG-P­(DOTA-C 6 ) and mPEG-P­(DOTA-C 10 )] amphiphilic DOTA backboned-bound branched polymers. As shown in Figure S2a and S2c, the characteristic peaks at 2.5–4.5 ppm and 1.1–1.5 ppm are assigned to DOTA and rigid carbon chains (1,6-hexamethylenediamine or 1,10-diaminodecane). ,, With the introduction of mPEG, new characteristic peaks (d–g) belonging to mPEG appeared (Figure S2b and S 2d). , In addition, the characteristic peak at around 8.0 ppm is assigned to the carboxyl group of DOTA.…”

“…As shown in Figure S2a and S2c, the characteristic peaks at 2.5−4.5 ppm and 1.1−1.5 ppm are assigned to DOTA and rigid carbon chains (1,6-hexamethylenediamine or 1,10diaminodecane). 18,35,36 With the introduction of mPEG, new characteristic peaks (d−g) belonging to mPEG appeared (Figure S2b and S 2d). 37,38 In addition, the characteristic peak at around 8.0 ppm is assigned to the carboxyl group of DOTA.…”

“…As shown in Figure S3, the sharp band at 1650 cm −1 is attributed to the C�O stretching of the amide carbonyl derived from the reaction of EDTA dianhydride and primary or secondary amines (present in 1,4,7,10-tetraazacyclododecane, 1,6-hexamethylenediamine, 1,10-diaminodecane, and mPEG). 18,35,39 With the introduction of mPEG, a new band at 1100 cm −1 belonging to C−O−C of mPEG in mPEG-P(DOTA-C 6 ) and mPEG-P(DOTA-C 10 ) appeared. The bands at 2950 and 2850 cm −1 are attributed to the C−H stretching in DOTA, 1,6hexamethylenediamine, 1,10-diaminodecane, and mPEG.…”