Synthesis of New Poly(ether ketone)s Derived from Biobased Diols

New poly(ether-phosphoramide)s sulfides based on green resources as sensitive films for the specific impedimetric detection of nickel ions

For the development of selective and sensitive chemical sensors, we have developed a new family of poly(ether-phosphoramide) polymers. These polymers were obtained with satisfactory yields by nucleophilic aromatic polycondensation using isosorbide as green resources, and bisphenol A with two novel difluoro phosphinothioic amide monomers. Unprecedented, the thiophosphorylated aminoheterocycles monomers, functionalized with two heterocyclic amine, N-methylpiperazine and morpholine were successfully obtained by nucleophilic substitution reaction of P(S)-Cl compound. The resulting polymers were characterized by different analytical techniques (NMR, MALDI-ToF MS, GPC, DSC, and ATG). The resulting partially green polymers, having tertiary phosphine sulfide with P-N side chain functionalities along the main chain of polymers are the sensitive film at the surface of a gold electrode for the impedimetric detection of Cd, Ni, Pb and Hg. The bio-based poly(ether-phosphoramide) functionalized with N-methylpiperazine modified sensor showed better analytical performance than petrochemical based polymers for the detection of Ni²⁺. A detection limit of 50 pM was obtained which is very low compared to the previously published electrochemical sensors for nickel detection.

A Sensitive Impedimetric Sensor Based on Biosourced Polyphosphine Films for the Detection of Lead Ions

In this work, impedimetric sensors were developed for the detection of the four WFD heavy metals Pb2+, Cd2+, Hg2+ and Ni2+, by the modification of a gold electrode with four partially biosourced polyphosphine polymers. These polymers were obtained with satisfactory yields by polycondensation of the bis(4-fluorophenyl)(4-methylphenyl)phosphine sulfide and the bis(4-fluorophenyl)(4-methylphenyl)phosphine oxide using isosorbide or bisphenol A. The chemical structures and number-average molecular weights of the resulting polymers were determined by NMR spectroscopy (1H, 19F, and 31P) and by size exclusion chromatography. Glass transition temperatures varied between 184 and 202 °C depending on the composition of polymers. The bio-based poly(etherphosphine) oxide modified sensor showed better analytical performance than petrochemical based oxide for the detection of Pb2+. A detection limit of 10−10 g/L or 0.5 pM, which is 104 times lower than that of the anodic stripping voltammetric and the potentiometric sensors. A reversibility is obtained through rinsing of the impedimetric sensor with an EDTA solution.

Study on the Synthetic Characteristics of Biomass-Derived Isosorbide-Based Poly(arylene ether ketone)s for Sustainable Super Engineering Plastic

Demand for the development of novel polymers derived from biomass that can replace petroleum resources has been increasing. In this study, biomass-derived isosorbide was used as a monomer in the polymerization of poly(arylene ether ketone)s, and its synthetic characteristics were investigated. As a phase-transfer catalyst, crown ether has increased the weight-average molecular weight of polymers over 100 kg/mol by improving the reaction efficiency of isosorbide and minimizing the effect of moisture. By controlling the experimental parameters such as halogen monomer, polymerization solvent, time, and temperature, the optimal conditions were found to be fluorine-type monomer, dimethyl sulfoxide, 24 h, and 155 °C, respectively. Biomass contents from isosorbide-based polymers were determined by nuclear magnetic resonance and accelerator mass spectroscopy. The synthesized polymer resulted in a high molecular weight that enabled the preparation of transparent polymer films by the solution casting method despite its weak thermal degradation stability compared to aromatic polysulfone. The melt injection molding process was enabled by the addition of plasticizer. The tensile properties were comparable or superior to those of commercial petrochemical specimens of similar molecular weight. Interestingly, the prepared specimens exhibited a significantly lower coefficient of thermal expansion at high temperatures over 150 °C compared to polysulfone.

Sustainable and recyclable super engineering thermoplastic from biorenewable monomer

Environmental and health concerns force the search for sustainable super engineering plastics (SEPs) that utilise bio-derived cyclic monomers, e.g. isosorbide instead of restricted petrochemicals. However, previously reported bio-derived thermosets or thermoplastics rarely offer thermal/mechanical properties, scalability, or recycling that match those of petrochemical SEPs. Here we use a phase transfer catalyst to synthesise an isosorbide-based polymer with a high molecular weight >100 kg mol-1, which is reproducible at a 1-kg-scale production. It is transparent and solvent/melt-processible for recycling, with a glass transition temperature of 212 °C, a tensile strength of 78 MPa, and a thermal expansion coefficient of 23.8 ppm K-1. Such a performance combination has not been reported before for bio-based thermoplastics, petrochemical SEPs, or thermosets. Interestingly, quantum chemical simulations show the alicyclic bicyclic ring structure of isosorbide imposes stronger geometric restraint to polymer chain than the aromatic group of bisphenol-A.

Hyperbranched cyclic and multicyclic poly(etherketone)s by polycondensation of isosorbide and isomannide with 2,6,4′-trifluorobenzophenone and 1,3,5-tris(4-fluorobenzoyl) benzene

1,3,5-Tris(4-fluorobenzoyl)benzene (TFBB) and 2,6,4′-trifluorobenzophenone (TFB) were polycondensed with isosorbide and isomanide. All polycondensations were performed in a mixture of dimethyl sulfoxide and toluene with potassium carbonate as promotor. Optimal concentration to avoid gelation was set at 0.06 mol L−1. The different cyclization tendencies on the basis of monomers conformations are discussed. In the TFB series, the feed ratio isosorbide/TFB was varied from 1.0:1.0 to 1.5:1.0. A majority of linear and hyperbranched species were identified as main reaction products by matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry regardless of the diol with slight cyclization tendency for isomannide. When TFBB was polycondensed with isosorbide, the cyclization tendency was significantly improved. The products obtained at a feed ratio of 1.41/1.0 and 1.51/1.0 were rich in cyclic and multicyclic species. More interesting results were obtained from the polycondensation of TFBB and isomannide, giving rise majoritarily to cyclic, bicyclic, and multicyclic species. Differential scanning calorimetric measurements indicated high glass transition temperature (around 200°C).