Synthesis and Characterization of Unsaturated Succinic Acid Biobased Polyester Resins

Abstract

Polymers from renewable feedstocks are receiving increasing attention as the awareness about environmental issues derived from petroleum exploitation and waste accumulation is growing. With unsaturated polyester resins being one of the most used classes of polymers worldwide, the utilization of biobased monomers for manufacturing is more relevant than ever. In the present work, succinic acid, one of the most promising biobased building blocks, was incorporated in the structure of the resins in question to increase their biobased content. By reacting with ethylene glycol (EG) or poly(ethylene glycol) and maleic anhydride (MA) at several molar rations, unsaturated polyester resins (UPRs) were prepared. Their synthesis was evaluated by a variety of spectroscopical techniques, and their rheological properties made use of the reactive diluent mandatory for facilitating processing. Thus, in a second stage acrylic acid (AA) was used as cross-linking agent in the present of initiators and accelerators producing thermosetting resins. Differential scanning calorimetry (DSC) was employed to screen the cross-linking procedure, whereas with X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) it was proven that thermosetting resins were prepared. The thermal stability of the cured materials was evaluated by thermogravimetric analysis (TGA).

Novel Biobased Polyester Resins for Wood Applications: Morphological, Thermal, and Chemical Characterization

“…(2021), apart from the increased intensity of the bands between 1100 and 900 cm −1 , due to 1025 cm −1 band's contribution of the wood veneer. [ 4 ] Finally, PPEGSM 25–75 (Figure 2c) presents a more intense absorbance band at 1100 cm −1 , which corresponds to C–O–C stretching of PEG.…”

“…The synthesized UPRs were mixed with AA in a mass ratio of 1:2, while 3 wt% methylethylketone peroxide (MEKP) and 3 wt% Co(II) octoate were added as initiator and accelerator, respectively. [ 4 ] Three‐layer composite specimens were prepared from wood veneers (0.1 × 2.5 × 10 cm) glued together with the six experimental resins, in order to examine their interaction. In every case, 250–300 g m −2 of resin was spread on both sides of the middle veneer.…”

“…[6,7] For both of the two groups of experimental resins, namely PESM and PPEGSM, the collected spectra show no particular differentiation in comparison with the corresponding spectra from the cured resins, as presented by Papadopoulos et al ( 2021), apart from the increased intensity of the bands between 1100 and 900 cm −1 , due to 1025 cm −1 band's contribution of the wood veneer. [4] Finally, PPEGSM 25-75 (Figure 2c) presents a more intense absorbance band at 1100 cm −1 , which corresponds to C-O-C stretching of PEG.…”

“…[1][2][3] In a recent study, we demonstrated the synthesis of novel UPRs based on succinic acid (SA), maleic anhydrite, ethylene glycol (EG), and poly(ethylene glycol) with molecular weight 200 (PEG200), which are among the most important biobased monomers, cross-linked with acrylic acid (AA), also able to be produced by means of green routes. [4] shows the chemical structure of the experimental resins, which are divided in two groups; EG and PEG200 characterize PESM and PPEGSM groups, respectively, while SA and maleic anhydrite were used in both cases.…”

Development of high‐performance partially biobased thermoset polyester using renewable building blocks from isosorbide, 1,3‐propanediol, and fumaric acid

“…39 The band appearing in (c) (ca. 1645 cm À1 ) can be ascribed to the stretching vibration of the ( C C ) double bond from fumaric acid, 40 where the characteristic vibrations arising from the double bond of fumaric moieties decreased as the ratio between saturated and unsaturated acid increased (in both Groups I and II). In this context, it is possible to observe the opposite behavior in (d) for the characteristic bands of the aromatic ring in the regions 1605-1579 cm À1 and 1491-1454 cm À1 .…”