Solution Polycondensation Research Articles

Aromatic (co)polycarbonates bearing pendant 2,3-dimethylmaleimido group based upon a new phthalimidine-containing “cardo” bisphenol

A new “cardo” bisphenol viz., 1-(2-(1,1-bis(4-hydroxyphenyl)-3-oxoisoindolin-2-yl)ethyl)-3,4-dimethyl-1H-pyrrole-2,5-dione (PPH-MA) was synthesized in a two-step reaction sequence starting from phenolphthalein. PPH-MA was utilized as a step-growth monomer for the synthesis of a homo- and fourco-polycarbonates bearing pendant 2,3-dimethylmaleimido groups (PC-MAs) via solution polycondensation of PPH-MA or various mol % compositions of PPH-MA and bisphenol-A, respectively, with triphosgene.1H NMR spectroscopy confirmed the chemical structure and composition of PC-MAs. Inherent viscosity and number average molecular weight values of PC-MAs were in the range 0.45–0.64 dL g−1 and 18,300 − 36,200 g mol−1, respectively, indicating the formation of polymers of medium to reasonably high molecular weights. Tough, transparent and flexible films of PC-MAs could be cast from chloroform solution. X-ray diffraction studies indicated the amorphous nature of PC-MAs. The 10% weight loss temperature (T10) values of PC-MAs were in the range 373–443 °C indicating their good thermal stability.

Aromatic (Co)polycarbonates bearing pendant norbornenyl groups: Synthesis, characterization and post-polymerization modification

A homo- and three co-polycarbonates (PC-NBs) bearing pendant norbornenyl groups were synthesized via solution polycondensation of triphosgene with 4, 4'-(bicyclo (2.2.1) hept-5-en-2 yl methylene) bis (2-methoxyphenol) (BPA-NB) or various mol % compositions of BPA-NB and bisphenol-A, respectively. 1H-NMR spectroscopy confirmed the chemical structure and composition of PC-NBs. Inherent viscosity and number-average molecular weight (Mn) values of PC-NBs were in the range 0.44 – 0.64 dL g−1 and 21,800 – 34,100 g mol−1, respectively, indicating the formation of polymers of medium to reasonably high molecular weights. Tough, transparent, and flexible films of PC-NBs could be cast from chloroform solution. X-Ray diffraction studies indicated the amorphous nature of PC-NBs. Glass transition temperature (Tg) values, determined by DSC analysis, of PC-NBs were in the range 154 – 175°C and Tg values increased with the increase in mol % of BPA-NB. The post-polymerization modification of a representative PC-NB was demonstrated using 3,6-diphenyl-1,2,4,5-tetrazine via tetrazine-ene reaction.

Synthesis, reaction kinetics and properties of aromatic hyperbranched polyesters of different generations (G1 to G4) prepared via one-shot solution polycondensation

Synthesis, reaction kinetics and properties of aromatic hyperbranched polyesters of different generations (G1 to G4) prepared via one-shot solution polycondensation

Azo chromophore functionalized polyesters; Synthesis, characterizations and applications for efficient Electrocatalyst for oxygen evolution reaction and heavy metal ion detection

The current study focuses on the synthesis, characterization and investigation of the potential applications of azo chromophore functionalized polyesters and their composites with graphene derivatives. Employing the two-step diazotization coupling reaction, diazo diol monomers are synthesized. Subsequently, the azo polyesters are prepared via low-temperature solution polycondensation of the diazo diols with diacid chloride followed by the incorporation of graphene derivatives to obtain composite materials. Characterization techniques including Fourier transform Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Ultraviolet-Visible Diffuse reflectance spectroscopy (UV–Vis DRS) and Scanning electron microscopy (SEM) are employed to evaluate the chain structure, degree of crystallinity, optical properties and morphology. Further, their electrocatalytic activity towards the oxygen evolution reaction (OER) and detection ability toward heavy metal ion was evaluated. The results demonstrate enhanced catalytic and detection capabilities attributed to synergistic interactions between polymer and graphene components. This study provides significant insights into the development of efficient polymer-graphene hybrid materials, with potential applications in green chemistry and environmental monitoring.

Preparation and luminescence properties of polypyrrole-thiophene derivatives

Four kinds of polypyrrole-thiophene derivatives (PPy-Th) are prepared via solution polycondensation using pyrrole, 3-acylpyrrole, and 2-thenaldehyde as monomers. The structure, molecular weight, micromorphology, thermal degradation, ultraviolet-visible absorption, and luminescence performance of the derivatives are investigated by fourier transform infrared (FTIR), hydrogen nuclear magnetic resonance (1HNMR) spectroscopy, gel permeation chromatography (GPC), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis), and fluorescence spectra. FTIR and 1HNMR confirm that the derivatives have been successfully fabricated, and GPC indicates that the derivatives belong to oligomers with narrow molecular weight distribution. For acyl-substituted derivatives, the microstructures are mainly lamellar accumulation. Furthermore, under ultraviolet excitation, the derivatives can produce blue or green light emission, corresponding to the transitions of large π electrons in the conjugated structure of the molecular chains. Especially, the maximum emission wavelengths and Stokes shifts of the acyl-substituted derivatives are markedly larger than that of the non-acyl-substituted derivatives. The fluorescence quantum yield and band gap of the PVT are 4.46% and 2.01 eV, respectively. The fabricated PPy-Th can be used as luminescent materials in the development and application of polymer light-emitting diodes.

Novel catalyst-solvent system for high molecular weight polylactic acid synthesis via azeotropic solution polycondensation method

ABSTRACT Polycondensation for PLA synthesis is widely used due to its cost-effectiveness, but it often leads to low molecular weight PLA. To address this limitation, researchers have explored different catalysts, with the stannous chloride and p-toluene sulfonic acid combination being a popular choice. However, this method typically yields PLA with a MW of no more than 35000 g/mol, which is unsuitable for commercial applications. In contrast, ring-opening polymerization is considered the most effective method for synthesizing high MW PLA, despite its complexity and cost. Industrial-scale production predominantly employs ROP due to its capability to produce high MW PLA. The use of stannous octoate as a catalyst for ROP has shown promise in synthesizing higher MW PLA. However, its sensitivity to water limits its use in polycondensation, where stannous chloride is commonly employed but is not capable of synthesizing high MW PLA. This study explores the use of stannous octoate for the synthesis of high MW PLA with higher yield.

Synthesis of high molecular weight poly(ricinoleic acid) via a direct solution polycondensation in hydrophobic ionic liquids

Ricinoleic acid, a natural hydroxy fatty acid, is a good candidate for preparing biodegradable polymer elastomers. Herein, high molecular weight poly(ricinoleic acid) (PRA) with a weight average molecular weight up...

Salt transport of the carboxylated aromatic polyamide: Efforts to elucidate the structure-function relation of polyamide TFC desalination membranes

Five carboxylated polyamides with the number average molecular weight in the range of 15000–17000 Da, are synthesized via low-temperature solution polycondensation to study the effect of carboxyl group (-COOH) content on the carboxylated polyamide salt transport property. The glass transition temperature (Tg) of the carboxylated polyamide increases with the –COOH content due to the formation of more hydrogen bonds, which also leads to a decrease in free volume fraction (FFV). Interestingly, we observe that polymer having the –COOH content of 80%–100% possesses similar water uptake and KW, which provides a special perspective that how the –COOH group influences salt transport by excluding the effect of water content in polymer membranes. Water sorption can disrupt the hydrogen bonding within the –COOH groups, so setting out –COOH groups to bind water, leading to lower free water content and enhanced water/salt sorption selectivity. As the content of –COOH increases, the more negatively charged surface and stronger hydrogen bond interactions result in significant decrease in salt permeability (PS) and salt diffusivity (DS). These results implicate that the introduction of more –COOH groups to the polyamide layer can enhance the water/salt selectivity of TFC membrane without by changing the water sorption.

Tough and solvent-proof polyamide-hydrazides containing aliphatic and aromatic supramolecular segments

Tough polyamides are crucial materials useful in many fields such as water purification and automobiles. Here we present a synergistic strategy to toughen polyamides by mechanistic interplays between aliphatic and aromatic supramolecular segments. The aliphatic monomer of adipic acid dihydrazide (ADH) and the aromatic monomer of 4,4′-oxydianiline (ODA) were subjected to low-temperature solution polycondensation with terephthaloyl chloride to synthesize tough aromatic–aliphatic polyamides in one step. Tailoring the mismatched supramolecular interactions between ADH and ODA segments enabled the precise control on the crystallinity, microphase separation structure and energy dissipation ability of the polymers. By varying the ratio of ADH segments to ODA segments, we obtained the optimal aromatic–aliphatic polyamides with high strength (ultimate engineering stress, 43.3 MPa), high toughness (31.2 MJ m−3) and remarkable solvent resistance due to the reliable supramolecular crosslinks. This synergistic toughening strategy is potentially useful to guide the design and development of strong and tough polymeric materials.

Synthesis and fabrication of Cu-trimesic acid MOF anchored sulfonated Poly(2,5-benzimidazole) membranes for PEMFC applications

Porous metal–organic frameworks (MOFs) have started to gain attention because of their high crystallinity, porosity and structural designability, and they can facilitate proton conduction, but the poor membrane forming ability of MOFs limits their application. In this work, composite membranes based on poly (2,5-benzimidazole) (ABPBI) are focused, and the polymer ABPBI was synthesized from its monomer by solution polycondensation method using polyphosphoric acid (PPA) as solvent. Copper-trimesic acid (Cu-TMA) based metal-organic framework (MOF) was prepared by solvothermal synthesis. Varying ratios of MOF were incorporated into the ABPBI polymer matrix to develop a polymer electrolyte membrane (PEM) by solvent casting technique. Sulfonated composites were obtained by immersing the membranes in 20% sulfuric acid and the membranes were used to characterize the crystallographic structure and surface morphology by XRD and SEM. The membrane's mechanical, thermal and physicochemical properties, like tensile strength, thermogravimetric analysis, contact angle, water uptake, swelling ratio, ion exchange capacity, oxidative stability and proton conductivity, have also been evaluated. The 3 wt% Cu-TMA loaded membrane exhibited the highest proton conductivity of 0.039 S cm−1 at 80 °C, whereas the neat sABPBI showed 0.024 S cm−1. Cu-TMA/sABPBI based PEMs are good candidates for polymer electrolyte membrane fuel cells, as shown by their water uptake and ion exchange capacity values of 21.58% and 1.66 meq g−1.

Favorable Heteroaromatic Thiazole-Based Polyurea Derivatives as Interesting Biologically Active Products.

This research sought to synthesize a new set of heteroaromatic thiazole-based polyurea derivatives with sulfur links in the polymers' main chains, which were denoted by the acronyms PU1-5. Using pyridine as a solvent, a diphenylsulfide-based aminothiazole monomer (M2) was polymerized via solution polycondensation with varied aromatic, aliphatic, and cyclic diisocyanates. Typical characterization methods were used to confirm the structures of the premonomer, monomer, and fully generated polymers. The XRD results revealed that aromatic-based polymers had higher crystallinity than aliphatic and cyclic derivatives. SEM was used to visualize the surfaces of PU1, PU4, and PU5, revealing spongy and porous shapes, shapes resembling wooden planks and sticks, and shapes resembling coral reefs with floral shapes at various magnifications. The polymers demonstrated thermal stability. The numerical results for PDTmax are listed in the following order, ranked from lowest to highest: PU1 < PU2 < PU3 < PU5 < PU4. The FDT values for the aliphatic-based derivatives (PU4 and PU5) were lower than those for the aromatic-based ones (616, 655, and 665 °C). PU3 showed the greatest inhibitory impact against the bacteria and fungi under investigation. In addition, PU4 and PU5 demonstrated antifungal activities that, in contrast with the other products, were on the lower end of the spectrum. Furthermore, the intended polymers were also tested for the presence of the proteins 1KNZ, 1JIJ, and 1IYL, which are frequently utilized as model organisms for E. coli (Gram-negative bacteria), S. aureus (Gram-positive bacteria), and C. albicans (fungal pathogens). This study's findings are consistent with the outcomes of the subjective screening.

Nonstoichiometric Migita-Kosugi-Stille Coupling Polycondensation based on Intramolecular Catalyst Transfer System

In this paper, a nonstoichiometric Migita-Kosugi-Stille coupling polycondensation based on intramolecular catalyst transfer systems has been reviewed. The achievement of those systems is significant from the viewpoints of (1) acquisition of new knowledge in the synthesis of semiconducting polymer materials, (2) unnecessary strict control in monomer feed ratios generally required for a single-phased solution polycondensation, (3) possible improvement of the monomer reactivity by varying feed ratios, and (4) possibility of controlled chain end groups and extension to the synthesis of all-conjugated block copolymers. In practice, naphthalene-diimide-, phthalimide-, and terephthalate-based π-conjugated polymers have been synthesized under imbalanced stoichiometric conditions, possessing much higher molecular weights than those based on Carothers/Flory’s theory. The results of various model reactions and DFT calculations have revealed that the origin of the intramolecular catalyst transfer phenomenon is related to the existence of carbonyl groups introduced at the ortho-position of dibromo aryl monomers used in excess as well as types of palladium catalysts/precatalysts. In the near future, the proposed nonstoichiometric Migita-Kosugi-Stille coupling polycondensation will be established by extending the adaptable monomers and further optimizing catalysts/precatalysts.

Synthesis and identification of aromatic poly (Ester-Amide) containing chalcone groups in backbone chain

The purpose of this research is to synthesize a new monomer (E)-5-(3-(4-aminophenyl)-3-oxoprop-1-en-1-yl)-2-hydroxybenzoic acid and poly (ester-amide) polymer. Chalcone compound, α, β- unsaturated ketone is a new monomer that includes both the functional group (-CO-CH=CH-) and α, β - unsaturated carbonyl group of the present system. It is prepared via the condensation of aryl ketone with an aromatic aldehyde in the presence of suitable condensation agents which is known as condensation of aldol. The monomer was reacted with (phthalic anhydride and maleic anhydride) by solution polycondensation reactions to yield polymer. The synthesized monomer and polymer were characterized via FT.IR-spectra, Nuclear magnetic resonance13 C.NMR-spectra, 1H.NMR-spectra] and DSC (Differential scanning calorimetry)]. The polymer demonstrated excellent thermal stability. The findings revealed that poly (ester-amide) was successfully synthesized by providing a good spectrum that improved the existing amide functional group (-CONH-) and ester functional group (-COO-) in the spectrum of prepared polymer, as well as the presence of chalcone functional groups(CO-CH=CH-) improved in the spectrum of monomer.

Catalyst-Free Single-Step Solution Polycondensation of Polyesters: Toward High Molar Masses and Control over the Molar Mass Range

Catalyst-Free Single-Step Solution Polycondensation of Polyesters: Toward High Molar Masses and Control over the Molar Mass Range

Synthesis, Characterization of Some Conductive Aromatic Polyamides/Fe3O4 NPs/ITO, and Their Utilization for Methotrexate Sensing

Here, we have synthesized four series of polyamide-conductive polymers and used them to modify Fe3O4 NPs/ITO electrodes. The ability of the modified electrodes to detect methotrexate (MTX) anticancer drug electrochemically was investigated. Synthesis of the target-conducting polyamides, P1a–d, P2a–d, P3a, P3b, P3d, and P4c-d, based on different aromatic moieties, such as ethyl 4-(2-(4H-pyrazol-4-ylidene)hydrazinyl)benzoate, diphenyl sulfone, diphenyl ether or phenyl, has been achieved. They were successfully prepared in good yield via solution–polycondensation reaction of the diamino monomers with different dicarboxylic acid chlorides in the presence of N-methyl-2-pyrrolidone (NMP) as a solvent and anhydrous LiCl as a catalyst. A model compound 4 was synthesized from one mole of ethyl-4-(2-(3, 5-diamino-4H-pyrazol-4-ylidene)hydrazinyl) benzoate (diamino monomer) (3) with two moles benzoyl chloride. The structure of the synthesized monomers and polymers was confirmed by elemental and spectral analyses. In addition, thermogravimetric analysis evaluated the thermal stabilities of these polyamides. Furthermore, the morphological properties of selected polyamides were examined using an scanning electron microscope. Polyamide/Fe3O4/ITO electrodes were prepared, and the electrochemical measurements were performed to measure the new polyamides’ conductivity and to detect the MTX anticancer drug in phosphate buffer saline using cyclic voltammetry. The polyamides (P3b and P4b)/Fe3O4/ITO electrodes showed the highest sensitivity and reversibility towards MTX.

Design, synthesis and characterization of novel fluorinated polyimide membranes with bulky pendant for gas transport

AbstractThree novel fluorinated polyimides (PIs) were synthesized via one‐step solution polycondensation from a new diamine monomer, 4‐(3‐methoxy‐4‐(difluoromethoxy)phenyl)‐2,6‐bis(4‐aminophenyl)pyridine, and three commercially available aromatic dianhydrides. The solubility, thermal, optical, hydrophobic and gas transport properties of the obtained PIs were investigated. The results demonstrated that these polymers present good solubility in dimethylformamide, N‐methylpyrrolidone, dimethylsulfoxide, dimethylacrylamide, CHCl3, tetrahydrofuran and CH2Cl2 at room temperature or upon heating. Meanwhile, they displayed excellent thermal properties with glass transition temperature of 261–345 °C, weight loss temperatures at 10% of 518–523 °C as well as char yield of 60–62% at 800 °C in nitrogen atmosphere. Furthermore, the PI membranes have good hydrophobic properties with water contact angle value in the range 90.1–92.0°. Moreover, they show excellent optical properties, with cut‐off wavelength (λcut‐off) values of 368–381 nm and wavelength values at 80% transmittance (λ80%) of 421–462 nm. The pure gas permeabilities of He, CO2, O2 and N2 of the PI membranes were measured by the method of constant volume–variable pressure. The PI containing 4,4′‐(hexafluoroisopropyl)diphthalic anhydride moiety exhibits the largest molecular chain spacing and free volume, giving the best gas transport performance in this work. Molecular simulation results show that the introduction of fluorine‐containing structure and bulky pendant into polymer backbones is beneficial for gas transport. © 2023 Society of Industrial Chemistry.

Lipase-catalyzed solution polycondensation of 1,4-butanediol and diethyl succinate: Effect of diphenyl ether concentration on enzyme stability, reuse and PBS molar mass distribution

Polybutylene Succinate (PBS) is a biodegradable polyester which can be produced from renewable monomers (provided by fermentation routes) and has been widely spread in value-added applications, such as in the biomedical sector. Regarding the synthesis routes of PBS for biomedical applications, enzymes have been gaining prominence, due to their high selectivity, milder operating temperature, absence of toxic metals and the possibility of reuse (when immobilized). Therefore, this work seeks to investigate the enzymatic polycondensation in solution, using diethyl succinate and 1,4-butanediol as monomers, Novozym 435 as biocatalyst, and diphenyl ether as solvent. The possibility of reusing the immobilized biocatalyst was also addressed. Solvent-free reactions, or containing 5 and 50 wt% of diphenyl ether were tested, at 70, 80 and 90 °C. Average molar masses were measured by Gel Permeation Chromatography to evaluate the enzyme performance in PBS synthesis. Furthermore, the kinetic behaviour of the synthesis was monitored by the formation of the by-product. The reactions containing 5 wt% of solvent at 80 °C and 90 °C proved to be more advantageous, resulting in Mw between 2.500 and 3.350 g.mol−1, in reaction times between 60 and 90 min. In this case, small additions of diphenyl ether presented diffusional advantages when compared to solvent-free processes. In addition, reuse tests of the biocatalyst were performed at 70 °C with 5 wt% of solvent. A pronounced decrease in the enzymatic activity was observed in the N435 reuse cycles, indicating that diphenyl ether affected the stability of the immobilized biocatalyst. Therefore, additional investigation is still needed in using green solvents that keep the immobilised biocatalyst's stability, providing subsidies for future works aimed at scale-up and commercial/industry production of PBS.

Facile synthesis of soluble, self-crosslinkable and crystalline polyimides with ultrahigh thermal/chemical resistance

Low-cost and processable polyimides with ultrahigh thermal/chemical stability is urgently demanded in microelectronic and aeronautics/astronautics industries. In this work, crystalline polyimides containing reactive cyano groups were synthesized from readily available monomers by facile one-step solution polycondensation method. The obtained polyimides are soluble at room temperature in the common solvents, and can be easily made into transparent polymer films. After curing, the resultant products become completely insoluble in any solvents, exhibiting excellent chemical stability. The glass transition temperature (Tg) and 5% thermal decomposition temperature (T5) for the cured polyimides are as high as 462 °C and 570 °C, respectively. The ultrahigh Tg and T5 together with good solubility are superior to most polyimides already reported in the literature. Moreover, the polyimide films are quite tough with the tensile strengths of 94–118 MPa, Young's moduli of 2.3–2.7 GPa and elongations at break of 5.3%–8.6%. The combination of facile synthesis method, solution-proccesability, excellent thermal/chemical resistance and mechanical property endows the polymers with promising applications in polymer films and composite materials.

Synthesis, Characterization and Thermal Properties of Photoresponsive Epoxy Resin Containing Benzylidene Units in the Main Chain

&#x0D; Abstract&#x0D; A photoresponsive epoxy resin containing benzylidene units in the main chain has been prepared from bis (4-hydroxybenzylidene) cyclohexanone and epichlorohydrin using solution polycondensation method. The resulting compound possessed both the oxirane ring and benzylidene units. Thus, it has been highlighted in practical applications. The chemical structure of epoxy resin was characterized by Fourier transform infrared (FT-IR) and (1H, 13C) nuclear magnetic resonance (NMR) spectroscopies. The photolysis via [2π + 2π] cycloaddition reaction of the epoxy resin in the chloroform solution was studied by the UV-irradiation (350 nm). The thermal properties results show that the resulting epoxy resin is stable until 350 °C and its glass transition temperature is about 140 °C, which they were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively, to demonstrate its potential in the industrial coatings. &#x0D; &#x0D;

Conducting Behavior of Bischalcone Derivatives

With the scope of bischalcone-based copolyesters can be used as semiconductors; two copolyesters were synthesized by the solution polycondensation method. The Bischalcone diol was analyzed by UV-Visible, FTIR, NMR (1H, 13C NMR) spectroscopy. Using the UV-Visible data, the bandgap energy of the Bischalcone diol was calculated and found to be 2.82 eV. The Physico-chemical properties like Inherent viscosity and refractive index of the copolyesters were determined. Spectral studies such as FTIR, 1H and 13C NMR spectroscopy. The thermal property of the copolyesters was analyzed by differential scanning calorimetry. The melting temperature of the PTMI is observed at 320°C, and PTMT exhibits 360°C. The PTMT shows higher stability than the PTMT copolyester. The highest ionic conductivity for PTMI is 3.50 x 10-4 (S cm-1). The PTMT copolyester shows -0.0035 KJ mol-1 whereas the PTMI copolyester shows 0.0005 KJ mol-1. The electrochemical impedance analysis and conductivity measurement were examined for the two copolyesters expecting semi-conducting behavior which can be a good candidate for the optoelectronics application.