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Poly(ethylene glycol 1,4-cyclohexanedimethylene isosorbide terephthalate) (PEICT) copolymers synthesized from isosorbide (ISB), 1,4-cyclohexanedimethanol (CHDM), ethylene glycol (EG) and terephthalic acid (PTA) via polycondensation are a class of heat-resistant bio-based polyesters. The content of biomass-sourced ISB has an important influence on the various properties of the terpolymers but lacks detailed study. Herein, we synthesized a series of amorphous terpolyesters with different contents of ISB by melt polycondensation of ISB, CHDM, EG and PTA in a 30 L reactor, and investigated the effect of ISB content on the thermal, mechanical, optical and rheological properties. As the content of ISB increasing, the complex viscosities of terpolyesters were increased and the intrinsic viscosities were decreased. The tensile strength was increased from 45.1 MPa for poly(ethylene glycol 1,4-cyclohexanedimethylene terephthalate) (PCTG)to 48.1 MPa for PEI13.2CTandthe Tg was increased from 83.5 °C for PCTG (ISB 0 mol%) to 98.8 °C for PEI13.2CT (ISB 13.2 mol%). All the values of Td,5%, and Td,max of the terpolyesters were higher than 395 °C and 425 °C. [ABSTRACT FROM AUTHOR]

Solid alkali KF/MgO catalysts were prepared using the impregnation method by combining alkali metal compounds with oxides, which performed the transesterification of isosorbide (IS) with dimethyl carbonate (DMC) into dicarboxymethyl isosorbide (DC). Characterization of the catalysts was conducted through X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and N2 adsorption–desorption analysis. The catalytic performance of KF/MgO was examined under diverse KF loading and calcination temperature conditions. The characterization of catalyst identified that the creation of innovative active components K2MgF4 and K2CO3 were produced at a calcination temperature of 500 ℃ and a KF loading amount of 40%. The catalyst of 40-KF/MgO-500 demonstrated the most effective, favourable activity and selectivity. Through the optimization of transesterification process conditions, it was discovered that the yield of DC was at its highest under the optimal reaction conditions of n(DMC)/n(IS) = 6.5, catalyst dosage of 0.21 wt% (relative to IS mass), transesterification temperature of 120 °C, and reaction time of 6 h. [ABSTRACT FROM AUTHOR]

The effects of triethyl citrate (TEC) on the viscoelastic properties of a copolycarbonate comprising isosorbide and 1,4-cyclohexanedimethanol (ISB-PC) were studied in both the molten and solid states. TEC acted as an antiplasticizer for ISB-PC and increased its modulus in the glassy state, as demonstrated in blends comprising 5 and 10 wt% TEC. Because antiplasticization reduces the free volume fraction, the water content of the copolycarbonate films, which is known to affect various properties, decreased following the addition of TEC. Furthermore, TEC greatly decreased the zero-shear viscosity. The experimental values were much lower than those predicted by the Berry–Fox formula. In other words, a small amount of TEC greatly enhances the flowability of ISB-PC. [ABSTRACT FROM AUTHOR]

The replacement of polymers derived from petrochemical resources has been a prominent area of focus in recent decades. Polymers used in engineering materials must exhibit mechanical strength and stiffness while maintaining performance through a broad temperature range. Most of the polyesters used as engineering materials are based on terephthalic acid (TPA) and its derivatives, which provide necessary rigidity to molecular chains due to an aromatic ring. Bio-based alternatives for TPA-based polyesters that are gaining popularity are the polyesters derived from 2,5-furandicarboxylic acid (FDCA). To broaden applicational possibilities, one effective way to achieve specific properties in targeted applications is to adjust the composition and structure of polymers using advanced polymer chemistry techniques. The incorporation of rigid diols such as isosorbide, 1,4-cyclohexanedimethanol (CHDM), and 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) should result in a greater stiffness of the molecular chains. This review extensively explores the effect of incorporating rigid diols on material properties through a review of research articles as well as patents. Moreover, this review mainly focuses on the polyesters and copolyesters synthesized via two-step melt polycondensation and its alterations due to the industrial importance of this method. Innovative synthesis strategies and the resulting material properties are presented. [ABSTRACT FROM AUTHOR]

Using the abundant and cost‐effective oleic acid and isosorbide with excellent properties as raw materials, the plasticizers of isosorbide di‐oleate (IDO) and isosorbide di‐epoxidized oleate (IDEO) with good plasticizing effect, low cost and green safety were synthesized by esterification and epoxidation reaction. The molecular structure of the synthesized plasticizers was characterized by FT‐IR and 1H NMR. The PVC shows better flexibility when IDEO or IDO plasticizer is used than commercial DOP. In particular, IDEO‐40 has 34% higher tensile strength and 17% higher elongation at break than DOP‐40. The introduction of epoxy groups on the carbon–carbon double bond of fatty acids meets the high thermal stability of plasticized film. The residual amount of IDEO‐40 is 7.01%, and at a high temperature of 180 °C, it can maintain high heat resistance for more than 220 min and transmittance of over 86%. Moreover, IDEO demonstrates excellent resistance to migration and volatilization. However, PVC films plasticized with IDO display reduced mechanical properties, cold resistance, and resistance to volatilization and migration due to the presence of non‐rotating carbon–carbon double bonds. The results indicate that these bio‐based plasticizers hold promise for practical applications in PVC products, offering improved environmental sustainability and performance characteristics. [ABSTRACT FROM AUTHOR]

An unsymmetrical PCN palladium pincer complex 2-{(E)-{{(R)-1-[(1R,5S,6R)-3,3-dimethyl-2,4,7-trioxabicyclo[3.3.0]octan-6-yl]ethyl}imino}methyl}-6-{[(diphenylphosphino)oxy] phenyl}palladium(II) chloride based on an iminophosphinite ligand bearing two fused five-membered cycles, one of which containing a THF ring, was prepared in an eight-reaction sequence from a sustainable and enantiopure starting material, isosorbide, in a 20% overall yield. [ABSTRACT FROM AUTHOR]

In recent years, non‐traditional intrinsic luminescence (NTIL) materials containing only ester groups in their molecules have been emerging and received extensive attention and research. Nevertheless, the existing NTIL materials still have the problems of low molecular weight and insufficient mechanical properties, which limit their further application. Isosorbide is a kind of bio‐based rigid diol monomer which is mainly used to improve the heat resistance and mechanical properties of materials all along. Besides, the ring‐opening reaction under acidic conditions makes isosorbide‐based materials exhibit some new functionalities. In this paper, a series of isosorbide‐based copolyesters with high molecular weight are synthesized by a simple and economical two‐step melt polycondensation method. It is found that, on the basis of improving the thermal and mechanical properties of the materials, copolyesters also exhibit fluorescence emission in the visible region at the excitation wavelength of 350 nm. And the fluorescence emission wavelength can be adjusted from 400 to 480. This study broadens the functional application of the isosorbide‐based materials and effectively enriches fluorescence mechanism of NTIL. [ABSTRACT FROM AUTHOR]

5(S)-((3aR,4R,6aR)-2,2-Dimethyltetrahydrofuro[3,4-d][1,3]dioxol-4-yl)-2-phenyl-4,5-dihydrooxazole was synthesized from isosorbide in a three-step sequence, with an overall yield of 46%. The first reaction step involves a single regioselective ring-opening reaction of isosorbide with Me3SiI in the presence of acetone followed by an intramolecular nucleophilic substitution to transform the iodoalcohol into its corresponding epoxide. The last reaction allows the formation of the oxazoline ring directly from the epoxide with benzonitrile in the presence of BF3·Et2O. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of different hydroxy-terminated silicones on the properties of polycarbonate-silicone copolymers (ICS-PC) by introducing flexible and hydrophobic silicone into isosorbide-based polycarbonate through melt transesterification- polycondensation method. Through compatibility and transesterification experiments, it is confirmed that the alcohol-hydroxyl polydimethylsiloxane (a-PDMS) has higher reactivity and silicone conversion than the phenol-hydroxyl polydimethylsiloxane (p-PDMS), but the conversion does not exceed 81%. Polyether-modified silicone (PEMS) exhibits better compatibility and higher reactivity, thus resulting in higher conversion that can reach 86%. Effects of the type and content of silicone on the glass transition temperature (Tg), optical transparency, saturated water absorption, and mechanical strength of ICS-PCs were also discussed. It is found that p-PDMS has higher Tg, hydrophobicity, and mechanical strength with similar silicone content, but the total transmittance does not exceed 60%. In contrast, the PEMS system exhibits better optical transparency due to its improved compatibility with the PC matrix, with a total transmittance of up to 73%, Tg exceeding 150 °C while maintaining excellent flexibility and hydrophobicity. These results are helpful to further improve the comprehensive properties of bio-based polycarbonates. [ABSTRACT FROM AUTHOR]

Diglycidil ether of isosorbide (DGEISO), a potential biobased substitute for petro-based epoxy resin, such as to diglycidil ether of bisphenol A (DGEBA), was synthesized with a classic epoxidation route using isosorbide, epichlorohydrin, and sodium hydroxide. Fourier-transform infrared spectroscopy (FTIR) an inexpensive and fast technique, was used to monitor the DGEISO synthesis by the conversion of epoxy groups, reaching a constant absorption index after 2.5 h of the reaction. Differential scanning calorimetry (DSC) scans displayed that DGEISO epoxy curing temperature with methyltetrahydrophtalic anhydride (MTHPA) is similar to diglycidil ether of bisphenol A (DGEBA) (~ 135 °C) in the whole range of the heating rates evaluated in this work (2.5–20 °C/min). The curing kinetics of both DGEISO/MTHPA and DGEBA/MTHPA were evaluated using the Friedman, Vyazovkin, and Ozawa model, whereas the first two models described the kinetics parameters with errors lower than 3%. Despite subtle differences in the investigated systems' different thermal properties, the similar curing behavior could be beneficial, suggesting the DGEISO resin could be a competitive replacement for epoxy resins. [ABSTRACT FROM AUTHOR]

Unsaturated polyester resins, one of the most important thermosets, are invariably produced from oil-based monomers. Their application is limited in areas where high thermal stability is required due to their low Tg. Besides, these resins contain 30–40% hazardous styrene as a reactive solvent. Therefore, developing bio-based solventless unsaturated polyester resin with medium to high thermomechanical properties compared to petrochemical-based counterparts is important. In order to achieve this, a series of branched bio-based unsaturated polyester resins were synthesized using bulk polymerization method in two steps. In the first step, four different intermediates were prepared by reacting glycerol (as a core molecule) with either isosorbide (diol), 1,3-propanediol (diol), 2,5-furandicarboxylic acid (saturated diacid), or adipic acid (saturated diacid). In the second step, the branched intermediate was end capped with methacrylic anhydride to introduce reactive sites for cross-linking on the branch ends. The chemical structure of the resins was characterized by 13C-NMR. FT-IR confirmed the polycondensation reaction in the first step and the end functionalization of the resins with methacrylic anhydride in the second step. The effect of 2,5-furandicarboxylic acid and isosorbide on thermomechanical and thermal properties was investigated using dynamic mechanical analysis, differential scanning calorimetry, and thermo-gravimetric analysis. Results indicated that 2,5-furandicarboxylic acid based resins had superior thermomechanical properties compared to a commercial reference unsaturated polyester resin, making them promising resins for high-temperature composite applications. For example, the resin based on 2,5-furandicarboxylic acid and isosorbide and the resin based on 2,5-furandicarboxylic acid and 1,3-propanediol gave glass transition temperatures of 173 °C and 148 °C, respectively. Although the synthesized 2,5-furandicarboxylic acid based resins had higher viscosity (22.7 Pas) than conventional unsaturated polyester (0.4–0.5 Pas) at room temperature, preheated resins can be used for making high-temperature-tolerance fiber-reinforced composite. [ABSTRACT FROM AUTHOR]

Development of biobased aliphatic polyesters with better mechanical (tensile) properties in film has attracted considerable attention. This report presents the synthesis of soluble network biobased aliphatic polyesters by acyclic diene metathesis (ADMET) polymerization of bis(undec-10-enyl)isosorbide diester [M1, dianhydro-D-glucityl bis(undec-10-enoate)] in the presence of a tri-arm crosslinker [CL, glycerol tris(undec-10-enoate)] using a ruthenium–carbene catalyst, and subsequent olefin hydrogenation using RhCl(PPh3)3. The resultant polymers, after hydrogenation (expressed as HCP1) and prepared in the presence of 1.0 mol% CL, showed better tensile properties than the linear polymer (HP1) with similar molecular weight [tensile strength (elongation at break): 20.8 MPa (282%) in HP1 vs. 35.4 MPa (572%) in HCP1]. It turned out that the polymer films prepared by the addition of CL during the polymerization (expressed as a 2-step approach) showed better tensile properties. The resultant polymer film also shows better tensile properties than the conventional polyolefins such as linear high density polyethylene, polypropylene, and low density polyethylene. [ABSTRACT FROM AUTHOR]

The rising concern of environmental issues from the non-degradable conventional polymers is triggering the development of sustainable and renewable polymers. Thermoplastic starch (TPS) has been known to have huge potential to substitute conventional synthetic polymers. A thermoplastic starch was prepared using a non-food bitter cassava starch with isosorbide as plasticizer. To improve the dispersion and interfacial affinity of thermoplastic starch and boost the compatibility between starch and isosorbide, citric acid (CA) was used as an additive. The influence of citric acid to the TPS was then investigated. The result shows that citric acid improved tensile strength from 8.68 MPa to 11.98 MPa. The addition of citric acid at a concentration of 1 – 10 wt % can increase glass transition temperature (Tg) from 48.81°C to 63.89°C and storage modulus at 25°C from 1.20 GPa to 3.47 GPa. Two degradation temperatures (Td) were detected which are Td1onset value was decrease from 83.32°C down to 79.78°C while Td2onset value was decrease from 275.29°C down to 247.17°C and Td2max from 311.12°C to 295.06°C. [ABSTRACT FROM AUTHOR]

Plasticizers are widely used in poly(vinyl chloride) (PVC), polylactic acid (PLA), thermoplastic starch (TPS), and other modified powder materials to enhance the flowability, flexibility, and processability of macromolecules. Because of the reprotoxicity of phthalates in animals and humans, certain phthalates have recently been banned in the United States and Europe. Biobased plasticizers from green biomass–derived renewable resources with low toxicity are expected to be a substitute for phthalates. Among a variety of newly developed biobased monomers, cardanol, and isosorbide are the two most promising materials because of their unique structural features. This review summarizes the research progress of cardanol‐ and isosorbide‐based plasticizers with synergistic effects of plasticization, thermal stabilization, and anti‐migration. By summarizing and analyzing the relationship between molecular structure of plasticizer and plasticizing performance, this review can provide theoretical guidance for future research on the design of isosorbide‐ and cardanol‐based plasticizers. Highlights: Biobased plasticizers with low toxicity are expected to replace certain phthalates.The plasticizing effect of single biobased plasticizer is not good.Biobased plasticizer with synergistic effects is required.There exists the trade‐off effect between the molecular weight and the compatibility.Epoxidized isosorbide ester can be used as a heat stabilizer. [ABSTRACT FROM AUTHOR]

Environmental issues are becoming more and more prominent, and bio‐based polymers are essential to alleviate environmental degradation by replacing traditional polymers. With this context, a new family of functional isosorbide‐based polyesters and polyamides with high glass transition temperature are prepared via Passerini‐Three component polymerization (P‐3CP). To optimize the P‐3CP conditions, the influence of the polymerization solvent, temperature, feed ratio on the molar mass of final polymers are investigated. The higher molar mass (up to 10100 g/mol) and yield (>70 %) are achieved under very mild conditions (30 °C, standard atmosphere). Functional side groups, such as alkenyl, alkynyl and methyl ester, were introduced into polymer structure via P‐3CP by using functional isocyanides. The obtained polyesters and polyamides are characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectroscopies, differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). All polymers are thermal stable and amorphous with variable glass transition temperatures (Tg). The obtained polyester has Tg up to 87.5 °C, while the Tg of polyamides (ISPA‐2) is detected to be 97.5 °C depending on the amide bonds in the polymer backbone and the benzene ring side groups. The cytotoxicity is investigated by the CCK‐8 assay against mBMSC cells to confirm the biological safety. Overall, this novel strategy provides an efficient approach to produce functional isosorbide‐based polyesters and polyamides, which are promising prospect for being applied to biodegradable materials. [ABSTRACT FROM AUTHOR]

Herein, we present a facile synthetic process for producing biomass‐derived isosorbide (ISB) dioxides using dimethyl dioxirane (DMDO) as an efficient oxidizing agent, which was generated in situ from acetone and KHSO5. To achieve high conversion and product yield, the KHSO5 concentration, KHSO5 flow rate, and reaction temperature were optimized. Under the optimal conditions, rapid and efficient epoxidation using the in situ‐generated DMDO was observed under ultrasonication, yielding the desired product within 35 min at 0 °C. This study offers a convenient and efficient method for generating biomass‐derived ISB building blocks, which have significant potential for the fabrication of bioplastics. [ABSTRACT FROM AUTHOR]

Isosorbide can be used as a third monomer in the synthesis of aliphatic polyesters, and its V-shaped bridging ring structure can effectively improve the rigidity of the copolyester molecular chain. In this work, a series of degradable polyester materials were prepared by modifying polybutylene succinate and using isosorbide as the third monomer. The degradation tests in this paper were implemented through the hydrolysis of copolyesters in distilled water, degradation in natural water and degradation tests in simulated natural environments. The results showed that PBS and its copolyesters can degrade under natural conditions, and the introduction of isosorbide can accelerate the degradation of copolyesters, which could effectively reduce pollutants in nature. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Viscoelastic properties of copolycarbonate materials comprising isosorbide (ISB) and cyclohexanedimethanol (CHDM) were studied as a function of the ISB content. In the glassy state, β dispersion was clearly detected in the dynamic mechanical spectra. The tensile storage modulus E′ at room temperature increased with the ISB content, and the glass transition temperature Tg, i.e., peak temperature of α dispersion, increased with the ISB content. It was found from oscillatory shear modulus that the rubbery plateau modulus GN0 decreased with the ISB content. The entanglement molecular weights Me were found to be 2330–3640, which were slightly higher than that of bisphenol-A polycarbonate and much lower than those of poly(methyl methacrylate) and polystyrene. The onset shear stress of shark-skin failure at capillary extrusion was evaluated and found to increase with the ISB content. [ABSTRACT FROM AUTHOR]

Bio-based cross-linkers can fulfill the role of enhancing additives in bio-sourced curable materials that do not compare with artificial resin precursors. Isosorbide dimethacrylate (ISDMMA) synthesized from isosorbide (ISD) can serve as a cross-linker from renewable sources. Isosorbide is a bicyclic carbon molecule produced by the reaction modification of sorbitol and the optimal conditions of this reaction were studied in this work. The reaction temperature of 130 °C and 1% w/w amount of para-toluenesulfonic acid (p-TSA) were determined as optimal and resulted in a yield of 81.9%. Isosorbide dimethacrylate was synthesized via nucleophilic substitution with methacrylic anhydride (MAA) with the conversion of 94.1% of anhydride. Formed ISD and ISDMMA were characterized via multiple verification methods (FT-IR, MS, 1H NMR, and XRD). Differential scanning calorimetry (DSC) proved the curability of ISDMMA (activation energy Ea of 146.2 kJ/mol) and the heat-resistant index of ISDMMA (Ts reaching value of 168.9) was determined using thermogravimetric analysis (TGA). Characterized ISDMMA was added to the precursor mixture containing methacrylated alkyl 3-hydroxybutyrates (methyl ester M3HBMMA and ethyl ester E3HBMMA), and the mixtures were cured via photo-initiation. The amount of ISDMMA cross-linker increased all measured parameters obtained via dynamic mechanical analysis (DMA), such as storage modulus (E') and glass transition temperature (Tg), and the calculated cross-linking densities (νe). Therefore, the enhancement influence of bio-based ISDMMA on resins from renewable sources was confirmed. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) synthesis based on poly(ethylene glycol) (PEG) with isosorbide (ISO) and pentamethylene diisocyanate (PDI), named (ISOPUs) was carried out targeting PUs from renewable sources. The cross‐linked ISOPUs were produced and the details of the curing kinetics were determined via Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). DSC scans displayed exotherms between 100 and 200°C, related to cross‐linking. ISO addition accelerated the curing and the maximum curing rate (Cmax), with 91°C and 0.2964 min−1 for the compound with 70% ISO. FTIR spectra confirmed the interaction between OH (ISO/PEG) and NCO (PDI) groups, with total NCO consumption (band at 2267 cm−1). Through the thermogravimetric analyses (TGA), the PU/70% ISO presented weight loss at 146°C due to the degradation of ISO. ISOPUs displayed a decreased activation energy (Ea) during curing over a range of 100 to 42 kJ/mol for 0 < α < 5%, as demonstrated using the Friedman model, and higher thermal stability as evidenced through TG analyses. Curing and degradation kinetics were modeled using Friedman (FR), Kissinger‐Akahira‐Sunose (KAS), and Ozawa‐Flynn‐Wall (OFW). Overall, ISO accelerated the curing rate and increased the degradation Ea, suggesting high thermal stability for PUs with intermediate ISO contents, that is, 30%–50%. [ABSTRACT FROM AUTHOR]

Bioderived polycarbonate (ISB-PC) was synthesized via transesterification and polycondensation of isosorbide (ISB) and diphenyl carbonate (DPC) using lithium acetoacetone as a catalyst. The resulting ISB-PC exhibited high glass transition temperatures similar to bisphenol A polycarbonate (BPA-PC) and was thermally stable up to 350 ℃. The incorporation of isosorbitol into the polymer chain imparted an improved mechanical property of ISB-PC, such as a higher bending and tensile modulus and higher elongation at break. ISB-PC can be readily cast into transparent films with a tensile strength of 73.3 MPa and a tensile modulus of 534 MPa. ISB-PC displayed high UV transmittance and possessed blue fluorescence under UV irradiation. At the same time, ISB-PC also has strong anti-yellowing ability. [ABSTRACT FROM AUTHOR]

Poly(isosorbide carbonate) (PIC) is an example of the shift from fossil to bio‐based feedstocks in polymeric materials. However, the naturally high hygroscopicity of isosorbide may lead to the bad dimensional stability of its polymers, limiting its application. This work aims to develop a series of isosorbide‐based copolycarbonates by introducing hydrophobic groups, such as alkane chains and aromatic rings, into the polymer backbone via one‐pot melt polycondensation. As expected, the molecular structure and steric hindrance of the comonomer have a remarkable effect on the water absorption of the copolycarbonates. Among the comonomers, tricyclo[5.2.1.0(2,6)]decanedimethanol with an alkane skeleton bridge effectively reduces the saturation water absorption by 61% compared to PIC. The water absorption mechanism and kinetics of the copolycarbonates are investigated. Moreover, the incorporation of comonomers in PIC not only exhibits stronger hydrophobicity, but also significantly improves its optical properties. Copolycarbonates obtained have a light transmittance of 92% and a refractive index of 1.5394, which are higher than those of PIC, along with better thermal stability, flexibility, and lower glass transition temperature. This work provides a new strategy for the design of isosorbide‐based polycarbonates for use in optics. [ABSTRACT FROM AUTHOR]

In this study, iso-sorbitol type polycarbonate (PIC) was synthesized with isosorbide (ISB) and diphenyl carbonate (DPC) as reactive monomers. The flexible co-monomers 1,4-butanediol (BDO) and 1,4-cyclohexane dimethanol (CHDM) were introduced to improve its property. Then, two iso-sorbitol type polycarbonate copolymers were obtained: Isosorbitol type polycarbonate copolymer (PIBC) containing 1,4-butanediol (BDO) and isosorbitol type polycarbonate copolymer (PICC) containing 1,4-cyclohexane dimethanol (CHDM). The results of 1H-NMR and FT-IR demonstrated that the structures of PC, PIC, PIBC, and PICC synthesized by the experiment were consistent with the theoretical structures. The results of the characteristic viscosity test suggested that the copolymer with high relative molecular weight was successfully prepared. The results of DSC and TGA revealed that the introduction of a flexible copolymer increased the relative molecular weight of the copolymer, decreased the glass transition temperature, and exerted little effect on the thermal stability of the copolymer. The mechanical properties test results unveiled that PICC has good mechanical properties. Owing to its excellent mechanical and thermal properties, there is a broad application prospect of the PICC as a green polycarbonate material. [ABSTRACT FROM AUTHOR]

Thermoplastic starch (TPS) has emerged as an essential alternative to produce environmentally friendly packaging; however, retrogradation is a disadvantage that affects its shelf life. This study analyzed the co-plasticizing effect of isosorbide on the mechanical, thermal, physicochemical, and microstructural properties and the retrogradation of films obtained by blown film extrusion from thermoplasticized starch with mixtures of glycerol and isosorbide in different ratios (3:0, 2:1, 1:2, and 0:3, respectively). The results showed that the higher concentration of isosorbide significantly increased the tensile strength; however, it reduced the elongation. Retrogradation modeled using the Avrami equation showed that the presence of isosorbide reduced the retrogradation rate (k) and modified the recrystallization mechanism (n). The relative crystallinity in the plasticized TPS films was reduced to 89%, and the adsorption significantly decreased. Isosorbide was very important in reducing the retrogradation of TPS. The best performance was obtained with the 2:1 ratio of glycerol/isosorbide due to the synergistic effect between the plasticizers. The results would allow tuning the properties of TPS films by combining glycerol/isosorbide in different ratios, which enables the design of materials tailored to potential application requirements. [ABSTRACT FROM AUTHOR]

In this study, isosorbide-based eco-friendly and effective plasticizers were synthesized and characterized. Isosorbide esterification was conducted using fatty acids with different alkyl-chain lengths; the optimal degree of isosorbide esterification was obtained after 6 h reaction at 220 °C with a short alkyl-chain fatty acid in the presence of the catalyst Ti(OBu)4. Isosorbide-based plasticizers of C12 or more alkyl-chain lengths exhibited low compatibility and did not form PVC sheets. An esterified isosorbide with long alkyl-chain length was epoxidized to enhance its plasticizing properties and enable low-cost production; the high epoxidation degree (91%) indicated efficient epoxidation by formic acid and hydrogen peroxide. The synthesized plasticizers, according to the alkyl-chain length, were used to fabricate PVC sheets; subsequently, their mechanical and thermal properties were analyzed. As the alkyl-chain length of the synthesized plasticizer increased, the tensile strength and modulus increased, while the elongation decreased. Furthermore, as the plasticizer content increased, the tensile strength and elongation decreased, while the plasticization efficiency increased. As the alkyl-chain length of the plasticizer increased, the molecular weight increased and the smaller molecules generated more free volume in the PVC chain. The thermal stability of the synthesized isosorbide-based plasticizers improved on increasing their alkyl-chain length, and was higher than that of a commercial plasticizer. Thus, the plasticizers synthesized in this study, particularly isosorbide di epoxidized oleate, could be used as eco-friendly and effective plasticizers for practical PVC applications. [ABSTRACT FROM AUTHOR]

Synthesis of bio‐polyurethane (Bio‐PU) using isosorbide (ISO) and poly(lactic acid) (PLA) diols, (propanediol based poly(lactic acid) (PLAP) and PLA esterified with Soybean oil (PLASO)) and pentamethylene (PDI) isocyanate were performed. Crosslinked Bio‐PUs were obtained, and the details of the curing kinetics were determined via Fourier transform infrared spectroscopy (FTIR) spectra and differential scanning calorimetry (DSC). Distinct curing behaviors between Bio‐PUs with different PLA diol formulations were observed. The addition of PLAP and PLASO increased the curing conversion at approximately 460% higher than Bio‐PU without PLA content, as verified by FTIR. The curing peak temperature (Tp) of Bio‐PUs with PLAP ranged from 94 to 163°C, while for PLASO Tp was 132–175°C. Bio‐PUs based on PLA diols displayed lower activation energy (Ea) during curing as demonstrated using Friedman model, and higher thermal stability as evidenced through thermogravimetric analyses. Reported data offer reliable tools to evaluate the best rote to synthesize biobased polyurethane and manipulate the degree of crosslinking based on composition and processing conditions, allowing product processing to the desired application. [ABSTRACT FROM AUTHOR]

Intramolecular electronic communication between electrochemically active groups connected by a bridging moiety can be modified through small changes in the spatial disposition of the redox active moieties and/or by the nature of the central core. In this study, chiral bio-based compounds, namely isomannide and isosorbide, were employed as cheap and easy-to-functionalize chiral scaffolds to bridge two ferrocenyl electroactive moieties. The crystal structures of both bis-ferrocenyl diester complexes were studied and they showed that the chirality of the bridge results in an open or tight helical crystal packing. The electron communication between the two electroactive units in the mixed valent monocations was also investigated using electrochemistry (cyclic voltammetry and differential pulsed voltammetry), and spectroelectrochemistry in the UV-Vis NIR. A computational study through time-dependent DFT was also employed to gain greater insight into the results obtained. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass-derived isosorbide (ISB) is a promising alternative to petroleum-based monomers in industrial plastics. In this study, ISB-based thermoplastic polyurethanes (ISB-TPUs) were prepared using ISB as a biomass chain extender, and the effects of the preparation route on the structural and physical properties of the resultant polymers were investigated. Prepolymer methods were more suitable for obtaining the desired molecular weights (MWs) and physical properties of ISB-TPUs than the one-shot method. The presence of the solvent and catalyst in the prepolymer step had significant effects on the structural and physical properties of the resultant polymer. Among several prepolymer conditions, the solvent- and catalyst-free methods were the most suitable for preparing commercial-level ISB-TPUs, with number- and weight-average MWs (Mn and Mw) of 32,881 and 90,929 g mol−1, respectively, and a tensile modulus (E) and ultimate tensile strength (UTS) of 12.0 and 40.2 MPa, respectively. In comparison, the presence of a catalyst in the prepolymer step resulted in lower MWs and mechanical properties (81,033 g mol−1 and 18.3 MPa of Mw and UTS, respectively). The co-existence of the catalyst/solvent led to a further decline in the properties of ISB-TPUs (26,506 and 10.0 MPa of Mw and UTS, respectively). ISB-TPU prepared via the solvent- and catalyst-free methods exhibited remarkable elastic recovery when subjected to up to 1000% strain in mechanical cycling tests. Rheological characterization confirmed the thermo-reversible phase change (thermoplasticity) of the polymer. [ABSTRACT FROM AUTHOR]

Three bio-based isosorbide bis(acid ester)s were synthesized by condensation of isosorbide with three symmetrical cyclic anhydrides (namely, succinic, diglycolic and phthalic anhydrides). The isosorbide-based diacids were obtained in high yields (79–97%) and converted to their diacid dichloride derivatives, which were then utilized to design series of bio-based polyester and poly(ester amide)s with wide range of thermal properties. The polyesters were synthesized in o-dichlorobenzene, utilizing either cis/trans-1,4-cyclohexanediol or 1,6-hexanediol, the polyesters were obtained in high yields (78–91%), showed good thermal stabilities, excellent solubility in organic solvents and glass transition temperatures in the range of -13.7 to 102.8 °C. Additionally, a series of novel aliphatic poly(ester amide)s was synthesized interfacially by polyamidation of the isosorbide bis(diglycolic acid) or isosorbide bis(succinic acid) derivatives with either trans-1,4-diaminocyclohexane or 1,6-hexanediamine. The aliphatic poly(ester amide)s obtained showed good thermal stabilities, good solubility in organic solvents and glass transition temperatures up to 129 °C. [ABSTRACT FROM AUTHOR]

Triethylammonium hydrogen sulfate (TEAHS) has been employed as an inexpensive protic ionic liquid catalyst for the preparation of various biomass-derived renewable compounds. TEAHS efficiently catalyzed the esterification of biomass-derived chemical intermediates such as levulinic acid, 2-furoic acid, stearic acid, and isosorbide. The scalable, cosolvent-free preparations were conducted in a batch-type glass pressure reactor, which provided excellent yields (> 80%) of the esters under moderate conditions. The TEAHS catalyst was conveniently separated from the reaction mixture and reused without significant loss of activity. [ABSTRACT FROM AUTHOR]

Long‐chain aliphatic copolyesters based on sebacic acid (SA) and isosorbide (IS), of renewable origin, are synthesized by a "green" and sustainable route, without the use of solvents, for the synthesis of polyurethanes (PUs). The polyesters are characterized by size exclusion chromatography (SEC), proton nuclear magnetic resonance (¹H NMR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetry (TG). ¹H NMR and FTIR analyses confirm the production of copolyesters with the incorporation of IS, while SEC indicates that the addition of IS to copolyesters decreases the molecular weights. The results suggest the formation of random copolymers in the presence of IS, which makes the polymer chains more rigid. The formation of PUs by the reaction of copolyesters with 1,8‐diisocyanatooctane is confirmed by FTIR. Thermal behavior is compatible with thermoplastic processing and use in different biomedical applications. [ABSTRACT FROM AUTHOR]

Copolycarbonate was synthesized by melt transesterification method, using diphenyl carbonate, isosorbide and 1,4-cyclohexanedimethanol (CHDM) as raw materials. The copolymer composition and random structure of the copolymer were determined by Fourier transform infrared and 1H NMR analysis. The DSC and TGA analysis showed that CHDM was introduced into the isosorbide polycarbonate chain, which effectively lowered the glass transition temperature of the polymer without lowering the thermal decomposition temperature. The glass transition temperature of the copolymer can be controlled by the addition amount of CHDM, and its processing performance can be improved. In addition, the introduction of CHDM did not reduce the high light transmittance (> 91.5%) of isosorbide polycarbonate. With the gradual increase of the amount of CHDM added, the refractive index of the copolymer decreases slightly. When the CHDM content is 30 mol%, the glass transition temperature (Tg)of the copolymer is 132.2 °C, the thermal decomposition temperature is > 350 °C, the refractive index is 1.4960, the Abbe number is 51, and the transmittance is 91.6%, and the haze is 1.07%. [ABSTRACT FROM AUTHOR]

Poly(2,5-furandicarboxylate)s incorporating aliphatic moieties represent a promising family of polyesters, typically entirely based on renewable resources and with tailored properties, notably degradability. This study aims to go beyond by developing poly(isosorbide 2,5-furandicarboxylate-co-dodecanedioate) copolyesters derived from isosorbide (Is), 2,5-furandicarboxylic acid (FDCA), and 1,12-dodecanedioic acid (DDA), and studying their degradation under environmental conditions, often overlooked, namely seawater conditions. These novel polyesters have been characterized in-depth using ATR-FTIR, 1H, and 13C NMR and XRD spectroscopies and thermal analysis (TGA and DSC). They showed enhanced thermal stability (up to 330 °C), and the glass transition temperature increased with the content of FDCA from ca. 9 to 60 °C. Regarding their (bio)degradation, the enzymatic conditions lead to the highest weight loss compared to simulated seawater conditions, with values matching 27% vs. 3% weight loss after 63 days of incubation, respectively. Copolymerization of biobased FDCA, Is, and DDA represents an optimal approach for shaping the thermal/(bio)degradation behaviors of these novel polyesters. [ABSTRACT FROM AUTHOR]

Biopolymers, which are biodegradable and inherently functional, have high potential for specialized applications (e.g., disposable and transient systems and biomedical treatment). For this, it is important to create composite materials with precisely defined chain interactions and tailored properties. This work shows that for a chitosan–gelatin material, both glycerol and isosorbide are effective plasticizers, but isosorbide could additionally disrupt the polyelectrolyte complexation (PEC) between the two biopolymers, which greatly impacts the glass transition temperature (Tg), mechanical properties, and water absorption. While glycerol-plasticized samples without nanofiller or with graphene oxide (GO) showed minimal water uptake, the addition of isosorbide and/or montmorillonite (MMT) made the materials hydrolytically unstable, likely due to disrupted PEC. However, these samples showed an opposite trend in surface hydrophilicity, which means surface chemistry is controlled differently from chain structure. This work highlights different mechanisms that control the different properties of dual-biopolymer systems and provides an updated definition of biopolymer plasticization, and thus could provide important knowledge for the future design of biopolymer composite materials with tailored surface hydrophilicity, overall hygroscopicity, and mechanical properties that meet specific application needs. [ABSTRACT FROM AUTHOR]

Herein, the successful design of a highly bio‐based family of unsaturated polyester resins (UPRs) is presented, comprising of an isosorbide (ISO) incorporated unsaturated polyester prepolymer (UP) and a reactive diluent of 4‐vinylguaiacol acetyl ester (ACVG). A series of UPs are prepared by copolymerizing ISO with other green monomers, i.e., itaconic acid, ethylene glycol and oxalic acid, in a variation of ISO fraction. The UP/ACVG mixtures exhibit very low viscosity ranging from 2.8 to 3.7 Pa s. After curing at 135 °C to form a network, the resulting thermosets exhibit remarkable improvements in terms of glass transition (Tg, about 131 °C), storage modulus (2564–3342 MPa), and tensile strength (around 76.6 MPa), which are significantly better than the UP thermosets reported in previous works, The incorporation of ISO units into the UPs reveals a favorable effect on thermal stability of the thermosets as well. The best Td5% is measured to be 320.4 °C, and the volatile molecular information collected using a TGA‐GC/MS set suggests that the decomposition mechanism of the cross‐linked resins becomes heat‐resistant due to the ISO incorporation. Moreover, after being reinforced by cotton fabrics, an outstanding compatibility between the ISO containing UPRs and cotton fibers is found to be suitable for composite fabrication. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Isosorbide‐based renewable semi‐fluorinated polymers were synthesized via base‐mediated step‐growth polycondensation of isosorbide diol monomer with bis‐trifluorovinyl ether (TFVE) monomer in excellent yields. As the first example employing secondary alcohols in this addition/elimination polymerization affording fluorinated arylene vinylene ether (FAVE) polymers, reasonable to high‐molecular weights (10–84 kDa) and reproducible glass transition temperatures (Tg) ranging from 120 to 130°C were achieved. Containing 23–31 wt.% renewable isosorbide repeat unit, the amorphous polymers are processable in common organic solvents and form tough, transparent films. Depending on basic conditions, these renewable semi‐fluorinated polymers contain reactive fluoroalkene enchainment for post‐polymerization functionalization and further retain the ability to thermally crosslink without the need for catalysts or initiators. Structural characterization of this complex asymmetric polymer was determined by multi‐nuclear NMR including multiple 2D‐NMR techniques. Renewable FAVE chemistry based on isosorbide presents an intriguing option for alternative renewable materials containing fluorine. [ABSTRACT FROM AUTHOR]

Preparation of isosorbide from cellulose by a catalytic one‐pot method under hydrothermal conditions is studied. Phosphate tantalum (TaOPO4) was prepared and used as support for the preparation of Ni/TaOPO4 via impregnation of Ni. The catalyst was characterized by X‐ray diffraction, H2‐TPR, NH3‐TPD, pyridine FTIR and Raman spectroscopy analysis. Results showed that the 5Ni/TaOPO4 (5 % loading of Ni) with a Brønsted/Lewis site (B/L) ratio of 0.153 showed the best catalytic performance and the total yields of sorbitol and isosorbide from cellulose reached 43 % under the conditions of 200 °C and 3 MPa H2 for 24 h. Both Lewis and Brønsted acid sites played crucial roles for the decomposition and dehydration reactions. The synergy of surface acid sites and reduction sites enhanced the cascade dehydration and hydrogenation reactions during the conversion of cellulose to isosorbide. This research is expected to broach a solution for the development of novel solid acid catalysts for the conversion of sugars into platform compounds. [ABSTRACT FROM AUTHOR]

The synergy of multicomponent reactions (MCRs) and metathesis chemistry is applied for the synthesis of bio‐based functional isosorbide polymers (i.e., polyesters) decorated with α‐acyloxy amide motif. The chemical structure of the polyesters that are not accessible by any other conventional methodologies is characterized in‐depth via nuclear magnetic resonance, size‐exclusion chromatography, and attenuated total reflectance infrared spectroscopy. It is also observed that the "biomass‐derived" carbon % of the polymers varied between 66.2 and 76.9. Moreover, the thermal properties of the novel isosorbide‐based polymers are investigated via thermogravimetric analysis and differential scanning calorimetry, revealing that the polymers are in the amorphous state, identified by the glass transition temperature (Tg) values below the human body temperature. The mechanical properties and the biocompatibility of the functional novel polyester derivative with the highest "biomass‐derived" carbon % are evaluated via dynamic mechanical analysis and cytotoxicity test. The exemplary polymer is biocompatible with chondrocyte cells in the conditions used in the tests. In summary, the complementary nature of isosorbide derivatives with MCRs and metathesis chemistry is utilized to illustrate the potential utility of isosorbide as a building block for polymers with prospective biomedical application (namely, as novel cartilage materials). [ABSTRACT FROM AUTHOR]

The remarkable elasticity and tensile strength found in natural elastomers are challenging to mimic. Synthetic elastomers typically feature covalently cross‐linked networks (rubbers), but this hinders their reprocessability. Physical cross‐linking via hydrogen bonding or ordered crystallite domains can afford reprocessable elastomers, but often at the cost of performance. Herein, we report the synthesis of ultra‐tough, reprocessable elastomers based on linear alternating polymers. The incorporation of a rigid isohexide adjacent to urethane moieties affords elastomers with exceptional strain hardening, strain rate dependent behavior, and high optical clarity. Distinct differences were observed between isomannide and isosorbide‐based elastomers where the latter displays superior tensile strength and strain recovery. These phenomena are attributed to the regiochemical irregularities in the polymers arising from their distinct stereochemistry and respective inter‐chain hydrogen bonding. [ABSTRACT FROM AUTHOR]

The remarkable elasticity and tensile strength found in natural elastomers are challenging to mimic. Synthetic elastomers typically feature covalently cross‐linked networks (rubbers), but this hinders their reprocessability. Physical cross‐linking via hydrogen bonding or ordered crystallite domains can afford reprocessable elastomers, but often at the cost of performance. Herein, we report the synthesis of ultra‐tough, reprocessable elastomers based on linear alternating polymers. The incorporation of a rigid isohexide adjacent to urethane moieties affords elastomers with exceptional strain hardening, strain rate dependent behavior, and high optical clarity. Distinct differences were observed between isomannide and isosorbide‐based elastomers where the latter displays superior tensile strength and strain recovery. These phenomena are attributed to the regiochemical irregularities in the polymers arising from their distinct stereochemistry and respective inter‐chain hydrogen bonding. [ABSTRACT FROM AUTHOR]

Isosorbide is one of the most interesting cellulosic‐derived molecules with great potential to be implemented in wide range of products that shaping our daily life. This Review describes the recent developments in the production of isosorbide from sorbitol in batch and continuous‐flow systems under hydrothermal conditions using solid acid catalysts. Moreover, the current hurdles and challenges regarding the synthesis of isosorbide from cellulosic biomass in continuous‐flow process using solid acid catalysts are summarized, as well as the scaling‐up of this process into pilot level, which will lead to an established industrial process with high sustainability metrics. [ABSTRACT FROM AUTHOR]

Isosorbide is a biodegradable bicyclic diol widely used for biopolymers, surfactants, plasticizers, solvents and pharmaceuticals production, which is obtained by dehydration of sorbitol. In this investigation the double cyclodehydration of D-sorbitol to isosorbide on Amberlyst 15 and KU-2-8 sulfonic acid resins at 120-140 C in the batch reactor under vacuum (150-170 mbar) without solvent was studied. It was found that the studied catalysts provide 78-88 % isosorbide yield with a complete conversion of sorbitol at 140 C for 3 h. More stable Amberlyst 15 produces 10 g of isosorbide per 1 g of catalyst for 3 h at 130 C. After 5 experiments for 3 h at 125 C acid site concentration on Amberlyst 15 surface reduced by only 4 %, sorbitol conversion and yield of products remain almost unchanged. KU-2-8 shows high initial catalytic activity, but after only one run this resin loses 40 % of sulfonic groups. Keywords: biomass; heterogeneous catalysis; isosorbide; polymers; sorbitol dehydration. [ABSTRACT FROM AUTHOR]

Isosorbide is a biobased compound which could become in the near future an advantageous competitor of petroleum-derived components in the synthesis of polymers of different nature. When the reactivity of isosorbide is not enough, it can be successfully transformed into secondary building blocks, such as isosorbide bis(methyl carbonate), which provides extra functionalities for polymerization reactions with diols or diamines. The present review summarizes the possibilities for isosorbide as a green raw material to be used in the synthesis of polycarbonates and polyurethanes to obtain products of similar or enhanced properties to the commercial equivalents. [ABSTRACT FROM AUTHOR]

In this article, we reported a new strategy to synthesize of isosorbide-based copolycarbonates with good flexibility and tunable thermal property via one-pot direct melt polycondensation of isosorbide (ISB), dimethyl carbonate (DMC) and 1,4-benzenedimethanol (BDM). The effect of different feed ratio on the chemical structure, molecular weight, thermal and mechanical property of copolycarbonates was in-depth studied. A series of metal ion-containing compounds as catalysts were used, and the copolycarbonates was synthesized with weight average molecular weight (Mw) of 80,300 and dispersity index below 1.78 by sodium tert-butoxide catalyst, and the reaction time was shorted to only 3.5 h with the ISB conversion up to 99.0%. Meanwhile, the Tg values realized controllable and tunable from 69 to 164 °C by varying the ratio of two diol monomers, and the influence of the structure of carbonyl carbon in repeating units of copolycarbonates on the thermal properties were demonstrated. Moreover, the results of dynamic mechanical analysis (DMA) implied that the flexibility of copolycarbonates was increased with increasing BDM content, and the results of scratch resistance and melting index of the copolycarbonates provided enormous prospect for the industrial application. Synopsis: A green synthetic pathway for high molecular weight and flexible isosorbide-based copolycarbonate was developed via one-pot melt polycondensation of isosorbide, dimethyl carbonate and 1,4-benzenedimethanol. [ABSTRACT FROM AUTHOR]

A series of chiral dopants derived from D-isosorbide were synthesized. Some of them exhibita monotropicsmecticA phase. Comparison of the melting points of these chiral dopants, the decrease of them is mainly driven by the large entropy change. The helical twisting power (HTP) values of these chiral dopants with branched alkyl chains, lateral fluoro-substituents and double bonds are lower than those of the chiral dopants with hexyloxy chains. Structural colored polymer films with a right-handed helix are prepared using these chiral dopants. [ABSTRACT FROM AUTHOR]

The current trend of developing novel biobased polymeric materials is focused more on utilizing the unique structural/physical properties of renewable building blocks towards niche market applications. In this work, with the aim of developing low‐crystallinity to amorphous polyesters with enhanced thermal properties, a series of copolyesters based on rigid and structurally asymmetric carbohydrate‐derived building blocks, namely furan‐2,5‐dicarboxylic acid and isosorbide, and 1,4‐butanediol were successfully synthesized using melt polycondensation. The copolyesters were obtained with varied chemical compositions and rather high molecular weights (Mn = 24 000–31 000 g mol−1) and intrinsic viscosities ([η] = 0.56–0.72 dL g−1). Incorporation of both building blocks significantly enhances the glass transition temperatures (Tg = 38–107 °C) of polyesters, and also efficiently inhibits the crystallization of the copolyesters. A low content of isosorbide (ca 10 mol%) leads to complete transition of the homopolyester to nearly fully amorphous materials. Detailed characterizations of the chemical structures and thermal properties of the synthesized copolyesters were conducted using various analytical techniques. In addition, hydrolytic and enzymatic degradations of the copolymers in the presence of porcine pancreatic lipase and cutinase were also investigated. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

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