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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; 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).

Poly(ethylene-co-isosorbide terephthalate) (PEIT) copolyesters could be used in various applications depending on their ability to crystallize. Moreover, the possibility to carry out solid-state post-condensation (SSP) is conditioned by its ability to sufficiently crystallize. The present study, thus, gives a systematic investigation of isothermal crystallization of these statistical copolyesters with isosorbide contents ranging from 4.8 to 20.8 mol.%. For each copolyester composition, the lowest isothermal half crystallization times and the highest Avrami constant (K) were obtained around 170 &deg, C. Over the range of composition that was studied, both melting points and melting enthalpies decreased with increasing amounts of isosorbide (from 250 to 207 &deg, C and from 55 to 28 J/g, respectively). On the contrary, half crystallization time displayed an exponential increase when increasing isosorbide contents in the studied range. Finally, structural and thermal analysis of PIT homopolyester are reported for the first time, showing that only ET moieties crystallized when PEIT was subjected to isothermal crystallization at 170 &deg, C.

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.

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.

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; Poly(butylene succinate) (PBS) is currently developing due to its biodegradability and the similarity of its mechanical properties to those of polyolefins. Relationships between the number average molar mass,(M) over bar (n), and solution viscosity such as [eta] and eta(red) were derived for this aliphatic polyester. (M) over bar (n) values were determined by end-group analysis and size exclusion chromatography (SEC). Mark-Houwink-Sakurada (MHS) parameters were proposed in two solvents and for the different molar masses and viscosity measurement methods. As an example, the MHS equations were respectively, [eta] = 6.4 10(-4).M-n (0.67) in chloroform and [eta] = 7.1.10(-4).(M) over bar (-0.69)(n) in 50/ 50 wt% 1,2-dichlorobenzene/ phenol at 25 degrees C for molar masses measured by SEC in hexafluoro isopropanol (HFIP) with poly(methyl methacrylate) (PMMA) standards. Empirical relationships were also suggested to derive (M) over bar (n)directly from reduced viscosity, eta(red), which is much easier to determine than intrinsic viscosity. With these data, the number average molar mass of PBS can be conveniently estimated from a single viscosity measurement. In addition, it was shown that PBS contains 1-2 wt% of cyclic oligomers produced during esterification and that molar masses determined by taking this fraction into account or not were significantly different, especially for long chains.

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.

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.

The mechanism involved in the crystallization of bacterial polyhydroxybutyrate (PHB) and poly(hydroxybutyrate-co-hydroxyhexanoate) P(HB-co-HH) induced by orotic acid as a nucleant was investigated by using differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and proton nuclear magnetic resonance spectroscopy (1H-NMR). GPC measurements both carried on solvent cast and hot pressed samples did not show any significant drop of the molecular weight caused by the addition of the nucleant, indicating that no chemical reaction happened during the nucleation process. This result was confirmed by 1H-NMR analysis of oligohydroxybutyrate (OHB) treated with an excess amount of orotic acid. The possibility of epitaxial growth of the polymer crystal on the surface of the nucleant crystal was then investigated. It was found that there is an outstanding crystalline lattice matching between the plane (100) of the PHB crystal and the plane (001) of the orotic acid crystal. In comparison, the matching obtained with conventional nucleating agents, such as boron nitride and talc, was worse. Moreover, some regular hydrogen bonds between the polyester and orotic acid could stabilize the physical process. According to these results, the physical mechanism involving the epitaxial matching between orotic acid and PHB appears to be the most probable nucleation mechanism. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The kinetics of crystallization induced by orotic acid (OA) and boron nitride (BN) as nucleating agents were investigated for bacterial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)s (P(HB-co-HH)s) containing from 0 to 18% HH monomer units. The nucleation efficiency of these two chemicals was investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). It was found that both orotic acid and boron nitride are able to nucleate the crystallization of PHB. In the case of P(HB-co-HH) copolymers, orotic acid showed an outstanding nucleating effect. The comparison of half-crystallization times shows that for P(HB-co-10% HH), the crystallization initiated by orotic acid is more than three time faster than the one induced by boron nitride (t1/2BN/t1/2OA(60°C) = 3.7 and t1/2BN/t1/2OA(90°C) = 4.5). According to the fact that orotic acid is a biodegradable, biocompatible and a nontoxic chemical, this nucleating agent is a promising solution for PHAs used in medical applications such as implants. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The isolation and the purification of bacterial polyhydroxyalkanoates are the key step of the process profitability in the fermentation system. That is why many scientists have studied this field for the production of this biodegradable polymer. The ideal method should lead to a high purity and recovery level at a low production cost. This paper reviews four isolation methods, i.e. solvent extraction of halosolvent and nonhalosolvent, digestion of non-polyhydroxyalkanoate cell material involving surfactants, sodium hypochlorite or enzyme, mechanical cell disruption methods like using bead mills and high pressure homogenization, and new methods like spontaneous liberation of poly(3-hydroxybutyrate), dissolved air flotation, air classification, or by using supercritical CO2. The pretreatment of cell disruption and the purification methods and analytical methods of polyhydroxyalkanoates are also presented.

This article presents and develops the thermodynamic correlation model to obtain the solubility of polyhydroxyalkanoates (PHAs) in solvents. This model offers a new way to evaluate the polymer solubility parameters and regressions between experimental solubility and solubility parameters. Important parameters influencing solubility such as temperature, polymer molecular weight, crystallinity, and the kind of PHAs were studied. Experiments were carried out on PHB-co-Hx copolymers of different contents. Finally, a model which takes into account these parameters were established and tested on 232 experimental points. The method developed could be used for the selection of a solvent with high efficiency, low price, and low toxicity. © 2007 American Institute of Chemical Engineers AIChE J, 2007

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.