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The synthesis and properties of amorphous poly(tricyclodecanedimethylene-co-isosorbide terephthalate) (PTIT) with isosorbide (IS) content ranging from 0 to 68 mol% relative to total diols amount we...

In this paper, the synthesis and properties of poly(1,4-cyclohexanedimethylene-co-isosorbide terephthalate) (PCIT) with isosorbide (IS) content ranging from 16 to 61 mol% relative to the total diols amount were investigated. Amorphous polymers were successfully synthesized without isosorbide ring hydration. Glass transition temperature (Tg) linearly increased of 1.1 °C for each molar percent of isosorbide included in the polyester, meanwhile melting temperature (Tm) linearly decreased of 2.1 °C for semi-crystalline samples (up to 25 mol% of isosorbide). Molar masses of semi-crystalline samples were easily increased using high temperature solid-state polymerization (SSP) and reduced viscosity (ηred) higher than 70 mL g−1 were obtained. Semi-crystalline samples exhibit outstanding impact resistance compared with commercial high performance copolyester, whereas amorphous copolyesters exhibit acceptable mechanical properties coupled with high thermal resistance. Results confirmed the promising association between isosorbide and 1,4-cyclohexanedimethanol to reach tunable thermal and mechanical properties, depending on the targeted applications.

International audience; Starch based materials are attractive bio-based alternative to fully synthetic polymers. Native starch has however limited thermoprocessability and properties and must be modified. In order to improve the properties of starch-graft-poly(butyl-acrylate-co-styrene) copolymers via a process as green as possible, we report herein a new method for the dual functionalization of the polysaccharide via a one pot one step reaction in aqueous medium combining free radical polymerizations and ring-opening chemistry. Poly(butyl acrylate) / poly(butyl acrylate-co-styrene) (ca. 60 000 g/mol) and oligo(-caprolactone) were grafted on starch with a grafting percentage up to 75 %. The copolymers show two glass transition temperatures: one around 55-60°C related to starch and a second attributed to the grafted vinyl polymers, from -46°C to 20°C depending on butyl acrylate/styrene ratio). The resulting dual functionalized materials exhibit excellent mechanical properties, with elongation at break in the range 20-210 %, while single functionalized starch shows less than 5 %.

International audience; Isosorbide monoacrylate (IMA) is a fully bio-based monomer formed by the reaction between isosorbide and acrylic acid. From a fundamental point of view and as a potential substitute for the current petro-based and carcinogenic monomers, it is crucial to understand its behaviour during a conventional radical polymerization. To this end, the radical polymerizability of IMA has been investigated in depth under various conditions (i.e. different solvents or [IMA]/[Initiator(AIBN)] ratios). In all cases, plateaus are reached for Mn. The Mayo method of IMA free radical polymerization was carried out and the transfer to monomer (CtrM) constant was determined to be up to 1.4 × 10−3. Depending on the molecular weight, PIMA with a large range of Tg from room temperature to higher than 100 °C could be obtained. Furthermore, the treatment of high-Tg PIMA with succinic anhydride leads to a high-performance thermoset featuring thermomechanical properties close to those of commercial epoxy resins such as DGEBA-based resins (Tg = 116 °C and E′ = 4 GPa).

Isosorbide monomethacrylate (IMMA) is a biobased monomer that appears as a potential substitute for current petrobased methacrylates to prepare high-performance sustainable polymers by free-radical polymerization technique. However, as the molecular weight of polymers can markedly affect their physical, mechanical and processing properties, it is crucial to understand the nature of the processes that control the growing of IMMA based polymer chains. To this end, the free radical polymerizability of IMMA has been investigated in depth under various conditions (solvent, conversion rate, [IMMA]/[AIBN] ratio). This study, based on the determination of chain transfer constants using the Mayo method, highlighted the key role of monomer and solvent transfer reactions for controlling molecular weight of PIMMA (CtrM = 5.0x10-4 ; CtrS (DMSO) = 4.0x10-4; CtrS (DMF) = 5.0x10-4; CtrS (Isopropanol/dioxane (1:6)) = 1.0x10-3). Knowing the parameters governing the free radical polymerization of IMMA, PIMMA with tailored molecular weight (from 2100 to 80200 g.mol−1) and Tg have been prepared and characterized. In particular, DSC analyses of PIMMA revealed the opportunity to prepare from low-Tg to high-Tg materials with different potential applications.

Organocatalysts are assessed for the insertion of isosorbide, a rigid, biobased diol monomer, into poly(ethylene terephthalate). A sulfonic acid (p-toluenesulfonic acid—APTS), an amidine base (1,8-diazabicyclo [5.4.0] undec-7-ene—DBU) and a guanidine base (1,5,7-triazabicyclo[4.4.0]dec-5-ene—TBD) successfully catalyze the polymerization. The reaction mechanisms are studied by density functional theory. A bifunctional activation is observed in the presence of the sulfonic acid, the carbonyl moiety being activated via the acidic proton of APTS and the alcohol via the basic oxygen. Regarding DBU, a mechanism based on a basic activation of the alcohol rather than a nucleophilic attack of the catalyst is evidenced. The difference observed between TBD and DBU is attributed to a better H-bonding ability of the former versus the latter. 304;9

The present invention relates to a crosslinkable composition for forming a polyurethane coating on different types of substrate. The present invention relates in particular to a polyurethane composition comprising isosorbide as a diol chain extender, and to the polyurethane coating obtained from this composition.

International audience; A series of branched poly(butylene succinate) (PBS) were synthesized with several branching agents namely trimethylol propane (TMP), malic acid, trimesic acid, citric acid and glycerol propoxylate. The structure of the branched polymers was analyzed by SEC and H-1-NMR. The effect of branching agent structure on crystallization was also investigated and played a significant role. Isothermal studies showed that glycerol propoxylate could act as a nucleating agent. By contrast high content of TMP disturbed the regularity of the chain and hindered the crystallization of PBS. From the non-isothermal kinetic study, it was found that glycerol propoxylate increased noticeably the crystallization rate due to the flexible structure of the branching agent. A secondary nucleation was observed with glycerol propoxylate attributed to the crystallization of amorphous fraction included between crystallites formed at the primary crystallization. Chain topology was obtained through rheological investigations and the synthesized polymers showed a typical behavior of a mixture of linear and randomly branched PBS. The incorporation of branches improved the processability of PBS for film blowing application and the modulus and the stress at break of the resulting film were significantly increased.

International audience; Thermoplastic polyurethanes (TPUs) from fatty acids dimer-based polyester polyols, 4,4′-methylene bis(phenylisocyanate) (MDI) and isosorbide (ISO) as chain extender were successfully synthesized by a two-stage synthesis.TPUs obtained from isosorbide were compared to the model 1,4-butanediol (BDO) −based materials.Differential scanning calorimetry revealed the phase-separated structure of these materials that displayed atypical thermoplastic elastomer behavior by dynamic mechanical analysis. Samples were further analyzed bytransmission electronic microscopy, atomic force microscopy and compression set; hardness and water uptakewere also monitored. Isosorbide was found to slightly increase the glass transition and melting temperatures ofMDI-based hard segments, and to slightly decrease the stability and quality of phase segregation. This resulted inan increase in rubber modulus and hardness, shape retention, in a slight increase in the temperature of the αrelaxation of the soft segment domains and in a characteristic microphase morphology. Moreover the use of therather hydrophobic fatty acid-based soft segment allowed to keep the water uptake at a rather low level, in spiteof the presence of isosorbide in the formulation.

International audience; The insertion of rigid monomers such as isosorbide into poly(ethylene terephthalate) (PET) allows for the access of polymers with improved properties, notably in terms of thermal stability. This biobased monomer is however poorly reactive, and harsh reaction conditions lead to color concerns regarding the resulting polymer. This has motivated the development of catalytic systems enabling an increase of the reaction rate and a good coloration. In this study, we have assessed bimetallic catalytic systems based on the main metals used for PET catalysis, i.e., antimony, germanium and titanium, for the synthesis of poly(ethylene terephthalate-co-isosorbide terephthalate) (PEIT). The Sb2O3/Ti(OiPr)4 combination leads to a high reaction rate while maintaining an acceptable coloration. On the other hand, combining Sb2O3 with GeO2 affords the formation of poly(ethylene terephthalate-co-isosorbide terephthalate) without coloration concerns and a reaction rate higher than that observed using the single metal catalysts. Molecular weights and microstructure including diethyleneglycol (DEG) and isosorbide contents are also discussed, together with the thermal properties of the resulting PEIT. The GeO2/Ti(OiPr)4 is also assessed, and leads to average performances.

Correction for ‘Isosorbide monoacrylate: a sustainable monomer for the production of fully bio-based polyacrylates and thermosets’ by Florine Nonque et al., Polym. Chem., 2020, 11, 6903–6909, DOI: 10.1039/D0PY00957A.

The melt synthesis of poly(butylene succinate)/silica (PBS/SiO2) nanocomposites is investigated via an in situ approach. The use of two types of nanosilica, fumed (or pyrogenic) silica and colloidal silica, is described. In all cases, the addition of silica favors an increase of the melt viscosity during the polycondensation step. This behavior is attributed to both polymer–silica interactions and PBS chain coupling via possible reaction with silica silanols. Biodegradable film is a promising application for PBS. In this context, it is proved that silica greatly facilitates PBS processing by extrusion blowing (a longitudinal draw ratio of 16 is attained). Moreover, tensile tests performed on films demonstrate significant reinforcement of the material with the addition of the nanofiller. The dispersion of the particles into the polymer matrix is assessed by transmission electron microscopy and further characterized by image analysis. It appears that pyrogenic and colloidal silica particles are regularly dispersed in the polymer matrix and that this dispersion is stable upon film blowing.

New catalytic systems are developed to increase the transesterification efficiency during the synthesis of poly(ethylene terephthalate-co-isosorbide terephthalate) with the aim of compensating for the lack of reactivity of the isosorbide and to reduce the coloration of the polymer. The combination of antimony oxide with a second metal (lithium-, magnesium-, or aluminium-based compounds) is investigated, leading to the discovery of innovative antimony-based bimetallic catalytic systems that exhibit a higher polymerization efficiency, even at high isosorbide contents (20%) and, in some cases, lower coloration.

National audience; The synthesis and characterization of photopolymerizable unsaturated polyester resins based on PET waste are described. The resins came from a depolymerization process based on the glycolysis of PET by diethylene glycol (DEG). Different molecular weights of glycolysates were synthesized. Then, the latter was functionalized by a methyl hemiester of maleic acid to obtain unsatured ,-bismaleate PET oligomers. In the presence of an electron donor monomer, such as triethylene glycol divinyl ether, these electron acceptor oligomers were copolymerized by way of charge-transfer complexes under UV irradiation. The reaction was monitored in situ by real-time IR spectroscopy to study the kinetics of photopolymerization. This one was studied in relation with the physical and chemical characteristics of oligoesters and the composition of mixtures containing divinyl ethers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1324-1335, 2007

Polyethylene terephthalate (PET) was alcoholised with ethylene glycol to synthesize hydroxytelechelic oligomers of PET. On the other hand, commercial hydroxytelechelic polyϵ-caprolactone was modified in order to synthesize carboxytelechelic polyϵ-caprolactone. The chemical structure of the products was investigated by 1H NMR. Multiblock copolyesters were then synthesized by polyesterification of hydroxytelechelic PET and carboxytelechelic polyϵ-caprolactone oligomers, using several catalysts and different reaction conditions, which have been linked with the average molecular weight of the obtained block copolyesters. It appeared that residual distannoxane species coming from glycolysis step are best catalyst for polyesterification reaction. The chemical structure of the synthesized copolyesters was investigated by size exclusion chromatography and 1H NMR. The thermal and thermomechanical behavior of the synthesized copolyesters was investigated by differential scanning calorimetry and by dynamic mechanical analyses. The ester–ester interchange reaction between the two types of oligopolyesters has been enlightened and estimated taking in account the different reaction parameters. This side reaction led to the miscibility of the two phases of the oligomers, that can be explained by a random structure of the copolyester, and prevented to obtain multiblock copolymer.

The object of this study was the synthesis of thermoplastic elastomer compounds by direct copolyesterification of reactive oligomers of poly(ethylene terephthalate) (PET) and of poly(tetramethylene oxide) (PTMO). PET was glycolysed to synthetise hydroxytelechelic oligomers of PET. Commercially available hydroxytelechelic oligomer. The chemical structures of these oligomers were investigated by 1 H NMR and size exclusion chromatography. Multiblock poly(ester-ether) was then obtained by polyesterification of the hydroxytelechelic and carboxytelechelic oligomers, using different catalysts and different reaction conditions. The best stoichiometric ratio was determined to lead to the highest M n . The chemical structure of the synthesised poly(ester-ether) was investigated by size exclusion chromatography and 1 H NMR. The thermal and thermomechanical behaviour of the synthesises poly(ester-ether) was investigated by differential scanning calorimetry and by dynamic mechanical analysis, and showed a thermoplastic elastomer behaviour. This product could also be an interesting was of chemically recycling PET waste.

The photochemical induced polymerization of vinylidene fluoride (VDF) with hydrogen peroxide, leading to original telechelic (or α,ω-difunctional) PVDF, is presented. The influence of the nature of the solvents and the [H2O2]0/[VDF]0 initial molar ratios ranging from 4 to 80% was investigated. It was shown that the lower this ratio, the higher the molecular weights of the produced telechelic polymers. 19 F -NMR spectroscopy enabled the degree of polymerization, ( DP n ) , of these fluorinated polymers or oligomers to be assessed. Interestingly, the reversed/normal ratio of VDF units in these fluorocompounds was low. The mechanism of the reaction was investigated and showed that the hydroxyl radical generated from hydrogen peroxide reacted mainly at the hydrogenated carbon atom, but also to the fluorinated site yielding CO2H end-functions. This is discussed.

Full Paper: Electron paramagnetic resonance spin probe techniques are used for the characterisation of structure and dynamics of selected microdomains of polyacrylate latices and films obtained from them. Analysis of the spectral line shapes provides quantitative data on the localisation and mobility of ionic and polar non-ionic low- molecular additives during the drying process. Such additives are highly mobile down to bulk water contents of only 5%. In the dried dispersions, ionic additives form aggregates, in which their local concentration exceeds their bulk concentration by at least a factor of ten. These aggregates can be "melted by rewetting and the ionic additives can be partially washed out if the drying is performed below the minimum film forming temperature (MFT). Surfactants in the initial dispersions are partially anchored with their hydrophobic tails in the polymer particles. The fraction of such anchored surfactant molecules increases continuously with decreasing water content. If the drying is performed only slightly below the MFT, the surfactants reorganise to inverse micelles. In films obtained by drying at a temperature significantly below the MFT, somewhat larger surfactant aggregates are formed during annealing.

Research toward bio-based and biodegradable polymers has received a lot of attention these last years, due to environmental concerns and the need to replace fossil resources. Starch is in this frame an interesting starting material due to its abundance and low cost. Native starch displays however, poor mechanical properties and is highly hydrophilic. New starch-based thermoplastic materials can be prepared to overcome these drawbacks by chemical modification, and notably graft copolymerization. A large range of polymers can be grafted on starch by ring-opening and radical polymerizations of various monomers in order to modulate the properties of the final product. Polymers can also be directly grafted onto starch using coupling strategies. This review presents the state of the art in the field.

International audience; The use of 1,4:3,6-dianhydrohexitols, isosorbide, isomannide and isoidide in polymers is reviewed. 1,4:3,6-Dianhydrohexitols are derived from renewable resources from cereal-based polysaccharides. In the field of polymeric materials, these diols are essentially employed to synthesize or modify polycondensates. Their attractive features as monomers are linked to their rigidity, chirality, non-toxicity, and the fact that they are not derived from petroleum. First, the synthesis of high glass transition temperature polymers with good thermomechanical resistance is possible. Second, the chiral nature of 1,4:3,6-dianhydrohexitols may lead to specific optical properties. Finally, biodegradable polymers can be obtained. The production of isosorbide at the industrial scale with a purity satisfying the requirements for polymer synthesis suggests that isosorbide will soon emerge in industrial polymer applications. However, a deciding factor will be the reduction of polymerization time of these low-reactivity monomers to values compatible with economically viable production processes. (C) 2009 Elsevier Ltd. All rights reserved.

International audience; The objective of this study was to synthesize thermoplastic elastomers by the direct copolyesterification of reactive oligomers of poly[(ethylene terephthalate)-co-(ecaprolactone)] (PET) and poly(propylene oxide) (PPO). The synthesis of hard segment oligomers was achieved in two steps. The first step consisted of the glycolysis of PET leading to a,o-hydroxyl functionalized oligomers. The second step corresponded to the ring opening polymerization of e-caprolactone onto the hydroxyl end groups of thePEToligomers. Commercially available hydroxytelechelic poly(propylene oxide) was modified to obtain carboxytelechelic poly(propylene oxide). The chemical structure of the product was investigated by 1H NMR and size exclusion chromatography (SEC). Multiblock poly(ester-ether) was then synthesizedbypolyesterificationofhydroxytelechelicpoly[( ethylene terephthalate)-co-(e-caprolactone)] with carboxytelechelic poly(propylene oxide) oligomers, using different catalysts and reaction conditions. The best stoichiometric ratio for the reaction was determined in order to obtain the highest possible Mn. The chemical structure of the synthesized poly(ester-ether) was investigated by size exclusion chromatography and 1H NMR. The thermal and thermomechanical behavior of the synthesized poly(ester-ether) was investigated by differential scanning calorimetry and dynamic mechanical analysis, which showed that the poly(ester-ether) behaved as a thermoplastic elastomer. This product could also be an interesting way for chemical recycling of PET waste.

In the presence of ethylene glycol, poly(ethylene terephthalate) (PET) undergoes chain scissions with the formation of α,ω-hydroxyl oligomers, through classical transesterification by alcoholysis. e-Caprolactone was subsequently added on the hydroxyl end groups of PET oligomers by ring-opening polymerization at different molar ratios of e-caprolactone to PET oligomers. The chemical structure of the products was investigated by size exclusion chromatography, 1 H NMR spectroscopy, and differential scanning calorimetry. A large majority of these products are soluble in common organic solvents. The thermal and 1 H NMR analyses reveal that the transesterification between base units of PET oligomers and e-caprolactone during the synthesis is always present whatever the reaction conditions. This phenomenon leads to copolymers having thermal properties different from those of PET. However, some cooligomers present the interest of keeping properties close to those of PET. The main purpose of this study was the synthesis of PET co-oligomers that are soluble in some organic solvents that would make their use easier, and so that they can be used further as hard segment precursers for polycondensation reactions.

The present invention relates to a crosslinkable composition for forming a polyurethane coating on different types of substrates. The present invention relates in particular to a polyurethane composition with a high biosourced monomer content, comprising isosorbide as a diol chain extender and a pentamethylene diisocyanate trimer; the invention also relates to the polyurethane coating obtained from this composition.