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Polysaccharide films prepared using water extraction of red algae represent an important group of environmentally-friendly materials suitable for industrial applications in food processing, medicine or electrical engineering. In this study, we prepared polysaccharide films from Furcellaria lumbricalis (FL) and Gigartina skottsbergii (GS) seaweed extracts and investigated their physical, chemical, and mechanical properties. Following contents of individual isolated fractions were observed by the nuclear magnetic resonance (NMR): ultrasonic water extraction of GS (GSUW) consisted of (1–3)-α-glycan 6-sulfate; ultrasonic carbonate-peroxide extraction (GSUCP) consisted of the same glycan and extra carrageenan hybrids µ-D6S and ν-D2S,6S observed for the first time in this study; extractions of FL and GS in boiling water under reflux (FLW, GSW) contained α-, θ-, λ-, µ-, ν-, and ζ-carrageenans and (1–3)-α-glycan partially sulphated at C6 or the most complex mixture of α-, β-, κ-, ι-, θ-, ζ-carrageenans, and (1–3)-α-glycan partially sulfated at C6, respectively. Spatially-resolved surface morphology and mechanical properties were evaluated by the atomic force microscopy and PeakForce quantitative nanomechanical mapping and correlated to the other investigated films properties. According to X-ray diffraction analysis, we observed no cellulose content or confirm the crystalline form of carrageenans in none of the studied polysaccharide films.

Films from Furcellaria lumbricalis (FL) and Gigartina skottsbergii (GS) seaweed extracts were prepared and their properties were investigated. According to NMR analysis of GS ultrasonic water (GSUW) extraction (1-3)-α-glycan 6-sulfate was isolated. The analogical treatment with carbonate-peroxide solution (GSUCP) resulted in a mixture of the same glycan and carrageenan hybrids µ-D6S and ν-D2S,6S observed for the first time in this study. The extraction of GS in boiling water under reflux (GSW) in comparison to FL (FLW), indicates that GSW consisted of the most complex mixture of α-, β-, κ-, ι-, θ-, ζ-carrageenans, (1-3)-α-glycan partially sulfated at C6, and µ-D6S and ν-D2S,6S hybrids. The analogical FLW extract contained α-, θ-, λ-, µ-, ν- and ζ-carrageenans and (1-3)-α-glycan partially sulphated at C6. SEC-MALS results indicate that molecular weight of chromatographic main peak (Mp) is decreasing: GSUCP (994 kg/mol) > GSUW (565 kg/mol) > FLW (498 kg/mol) > ι-carrageenan (264 kg/mol) > κ-carrageenan (174 kg/mol) > furcellaran (144 kg/mol) > GSW (78 kg/mol). Macromolecules conformation is varying from flexible random coil for κ-carrageenan to nearly compact spheres for ι-carrageenan. Furcellaran conformation is intermediate between κ-carrageenan and ι-carrageenan, specifically a little more compact than κ-carrageenan. XRD analysis confirmed no cellulose content in all prepared films. AFM and PF-QNM analysis showed relations between values of Rg and Mp and the values of surface roughness, reduced moduli, stiffness and adhesion.

The analysis of many polysaccharides is often complicated due to the heterogeneity in their structures. A computer approach is presented exploiting the experimental data from elemental analysis and high-resolution NMR experiments to estimate the individual anhydro-unit ratio. Our approach is based on the fact that elemental composition of a particular type of saccharide is the same for saccharide units, connected by glycosidic bonds forming the polysaccharide chain, or for the individual saccharide anhydro structures complemented by the relevant amount of water molecules. From the possible structures generated, the structure is chosen by the computation with the best fit (“score”) to the elemental composition. The method was tested on a heparin pentasaccharide using the 1% deviation of HSQC-integrated limits at 5% water content. The optimal limits for evaluation of heparin in various ionic forms (Na+, Li+, or NH4+) for the computation input were found by the HSQC integration of the anomeric signals and anhydro unit ratios calculated based on elemental analysis, AAS, and SEC-MALS analysis. The results of heparin from different sources, and in various ionic environments, indicate that the presented methodology could be used as the complementary approach to other experimental analytical techniques of heparin and heparin sulfate.

Intraocular liquids tamponade agents, such as perfluorocarbon liquids (PFCLs), semifluorinated alkanes (SFAs), silicone oils (SOs) and heavy silicone oils (HSOs), are a crucial intraoperative and/or postoperative tool in vitreoretinal surgery, in particular for the management of complex vitreoretinal diseases. However, their use is not without complications, which are potentially severe. Consequently, a growing interest has been devoted to the biocompatibility of these compounds and the adequacy of current regulations that should guarantee their safety. Obviously, an updated knowledge on research findings and potential risks associated to the use of intraocular liquid compounds is essential, not only for vitreoretinal surgeons, but also for any ophthalmologist involved in the management of patients receiving intraocular liquid tamponades. In light of this, the review provides a comprehensive characterisation of intraocular liquid tamponades, in terms of physical and chemical properties, current clinical use and possible complications. Moreover, this review focuses on the safety profile of these compounds, summarising the existing regulation and the available evidence on their biocompatibility.摘要: 眼内液体填充剂, 如全氟化碳液体 (PFCLs) 、半氟化烷烃 (SFAs) 、硅油 (SOs) 和重硅油 (HSOs), 是玻璃体视网膜手术中及术后重要的玻璃体填充物, 对于复杂的玻璃体视网膜疾病的治疗尤其重要。然而, 这些填充剂可产生甚至严重的并发症。因此, 人们越来越关注这些化合物的生物相容性以及现行法规是否足以保证其使用的安全性。显然, 不仅对玻璃体视网膜疾病的外科医生来说, 或是对任何参与眼内液体填充患者治疗的眼科医生来说, 对眼内液体填充剂的研究结果和潜在风险有最新的认识和了解是必不可少的。有鉴于此, 本文就眼内液体填充剂的理化性质、临床应用现状及可能产生的并发症作一综述。此外, 本文还对这些填充剂的安全性进行了汇总, 并总结了有关其生物相容性的现有法规和现有证据。.

Plastic is nowadays one of the most concerning pollution materials. Traditional and new biodegradable and bio-based plastics are continuously object of biodegradation assays and experiments using different plastic degrading organisms. The traditional approaches to verify the positive outcome of the biodegradation tests are generally the measurement of CO2 production or the reduction of plastic mass. We propose an innovative method to verify and to follow the biodegradation process by means of spectroscopic techniques using 13C labeled HDPE. The bioassimilation test is performed using the bacterial strain Rhodococcus ruber (ATCC 29672), well known to be able to degrade plastic material from the literature. CO2 produced during bio assimilation was trapped in the flask and measured by titration. A significantly higher production of CO2 within 45 days compared with blank and control conditions was an indication of the positive trend of bioassimilation test, which was then confirmed by NMR experiments. The bioassimilation test, the innovative technique to measure CO2 and the timing of the process are positive features for the development of a new standard legislation to measure and follow the biodegration of plastic materials or even only to follow plastic materials in the environment. The source and fate of plastic materials in the environment is one of the pivotal issues for plastic pollution, so a secure detection with carbon might be very helpful in decision making for the restoration from plastic pollution. The method would be applicable to all the plastic materials to test in order to verify the real biodegradable feature, or to follow in the environmental compartments the path of a plastic material.

Correction for ‘Wound healing properties of hyaluronan derivatives bearing ferulate residues’ by Giuseppe Valacchi et al., J. Mater. Chem. B, 2015, DOI: 10.1039/c5tb00661a.

In order to obtain new advanced functional materials capable of recognizing drug molecules, the polybenzofulvene backbone of molecular brush poly-6-MOEG-9-TM-BF3k has been functionalized with a “synthetic dynamic receptor” composed of two 1-adamantylurea moieties linked together by means of a dipropyleneamino bridge as in Meijer's bis(adamantylurea) pincer (BAUP). This functional material, bearing synthetic receptors potentially capable of recognizing/loading and then delivering drug molecules, was used to prepare colloidal drug delivery systems (by means of soft interaction with BAUP) for delivering the model anti-cancer drug doxorubicin (DOXO). The resulting nanostructured drug delivery systems containing the physically loaded drug were characterized in terms of drug loading and release, dimensions and zeta potential, and in vitro cell activity and uptake on two different cell lines (i.e. the human bronchial epithelial 16HBE and the human colon cancer HCT116). On normal cells, free DOXO was found to be more cytotoxic than DOXO-loaded nanogels at the higher tested concentration and, only on cancer cells, DOXO-loaded nanogels show similar or slightly higher cytotoxicity values than free DOXO, suggesting potential advantages in the treatment of cancer. These results were supported by fluorescence microscopy studies, which suggested that DOXO-loaded nanogels provide an extracellular reservoir of the drug, which is gradually released and internalized within the cells.

Stable hydrogels with tunable rheological properties were prepared by adding Ca2+ ions to aqueous dispersions of 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO)-oxidized and ultra-sonicated cellulose nanofibers (TOUS-CNFs). The gelation occurred by interaction among polyvalent cations and the carboxylic units introduced on TOUS-CNFs during the oxidation process. Both dynamic viscosity values and pseudoplastic rheological behaviour increased by increasing the Ca2+ concentration, confirming the cross-linking action of the bivalent cation. The hydrogels were proved to be suitable controlled release systems by measuring the diffusion coefficient of a drug model (ibuprofen, IB) by high-resolution magic angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy. IB was used both as free molecule and as a 1:1 pre-formed complex with &beta, cyclodextrin (IB/&beta, CD), showing in this latter case a lower diffusion coefficient. Finally, the cytocompatibility of the TOUS-CNFs/Ca2+ hydrogels was demonstrated in vitro by indirect and direct tests conducted on a L929 murine fibroblast cell line, achieving a percentage number of viable cells after 7 days higher than 70%.

The photo-oxidative degradation processes of bio-based PA11 nanocomposites containing montmorillonite (MMT) and the organo-modified Cloisite&reg, 30B were investigated to discriminate the influence of organo-modified components on the polymer durability. Indeed, despite the extensive studies reported, there are still ambiguous points to be clarified from the chemical point of view. To this aim, UV-aged materials were analyzed by Size Exclusion Chromatography (SEC), Inductively Coupled Plasma&ndash, Mass Spectrometry (ICP-MS) and Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). This enabled determining changes in both chemical structure and Molar Masses (MMs) induced by light, heat and oxygen exposure. The addition of organo-modified nanoclays strongly affected the PA11 light durability, triggering the macromolecular chains scission due to the typical &alpha, H, Norrish I and II mechanisms. However, the main contribution in boosting the photo-oxidative degradation is induced by iron impurities contained into the clays. Conversely, thermo-oxidation process performed at 215 &deg, C was unambiguously affected by the presence of the organo-modifiers, whose presence determined an enhancement of crosslinking reactions.

Stable hydrogels with tunable rheological properties were prepared by adding Ca2+ ions to aqueous dispersions of 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO)-oxidized and ultra-sonicated cellulose nanofibers (TOUS-CNFs). The gelation occurred by interaction among polyvalent cations and the carboxylic units introduced on TOUS-CNFs during the oxidation process. Both dynamic viscosity values and pseudoplastic rheological behaviour increased by increasing the Ca2+ concentration, confirming the cross-linking action of the bivalent cation. The hydrogels were proved to be suitable controlled release systems by measuring the diffusion coefficient of a drug model (ibuprofen, IB) by high-resolution magic angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy. IB was used both as free molecule and as a 1:1 pre-formed complex with β-cyclodextrin (IB/β-CD), showing in this latter case a lower diffusion coefficient. Finally, the cytocompatibility of the TOUS-CNFs/Ca2+ hydrogels was demonstrated in vitro by indirect and direct tests conducted on a L929 murine fibroblast cell line, achieving a percentage number of viable cells after 7 days higher than 70%.

Films made of xylan (X) and quaternized chitosan (QC) were prepared and the interactions of the polysaccharides on interfaces were discussed. According to elemental analysis, the X film contained also cellulose (31%) which could not be separated from the water suspension. The QC sample was soluble in water due to the presence of quaternized glucosamine units (4%) despite the presence of equal amounts of chitosan (CS, 48%) and chitin (CT, 48%). According to mechanical tests on QC/X = 1/3 composite film, the modulus and tensile strength values were the best from all mixtures measured, but still not better than on the film from X. We assume this is due to the sorption of xylan onto the surface of insoluble cellulose fibrils in the X film. Cyclic voltammetry indicates that the incorporation of X into the QC film decreases the overall positive charge provided by the QC. The X composite with net negative charge is indeed a barrier against the diffusion of ferricyanide anions. Based on TG/DTG/DTA analysis, the onset temperatures (OT) are decreasing with increasing X content in the blended films. X and QC films exhibited the highest OT values in comparison with the blended samples. The lowest OT temperature was observed at QC/X = 1/3. We think it is due to the thermocatalytic effect of the 4-O-methyl-D-glucuronate in X and the QC quaternary groups on the thermolysis–thermo-oxidation mechanism. According to AFM, the QC/X = 1/3 film exhibited the largest roughness values on both sides of the films, likely due to having the highest density of electrostatic interactions. XRD profiles of the films indicate some crystalline residues of cellulose in the xylan component as well as some chitin in the QC component. We assume that the properties are the result of the combination of the electrostatic interactions of carboxyl and quaternary groups of the soluble components of X and QC bonded to the surface of insoluble cellulose fibrils by hydrogen bonds. This probably results in both synergistic and antagonistic effects expressed by the improved or diminished values of determined properties. Acknowledgements We gratefully acknowledge funding from State programs #2003SP200280203 and 2003SP200280301; Slovak Granting Agency VEGA (Project Nos. 2/7030/7, 2/0087/11, 2/0007/13 and 2/0100/14). We thank Eva Hadzimov? for performing the TG/DTG/ DTA experiments. This contribution is also the result of the project implementation: Centre of Excellence for White-Green Biotechnology, ITMS 26220120054, supported by the Research & Development Operational Program funded by the ERDF. P.K. thanks Qatar University for QUUG-CAM-2017-1 grant funding. Scopus

In our study we used holocelluloses from sugar beet and bagasse for film preparation. Films from sugar beet holocellulose have better mechanical properties than from bagasse holocellulose. By subsequent carboxymethylation of bagasse holocellulose, films with better properties were produced. Specimens prepared from combined sugar beet and bagasse carboxymethylated holocellulose had the best mechanical properties. The results could be explained by the ratios of cellulose, arabinan, polygalacturonan and xylan content in individual films, based on the elemental analysis data. The use of microwaves to prepare holocellulose film speed up the process, but negatively affected the mechanical properties. Lignin content of the sugar beet holocellulose and bagasse samples was low and did not affect the mechanical properties. Both types of agricultural by-products could be used for preparation of composite film with high strength and stiffness suitable for broad range of applications.

Purpose We evaluated chemical composition, and molecular and rheological properties in 10 commercially available silicone oils (SilOils), focusing on siloxane chains of low molecular weight (LMW components, LMWC) that are known to be "impurities" produced during the SilOil synthesis process. Methods We assessed the type of SilOil polymer and molecular weight distribution (MWD) by spectroscopy and conventional size exclusion chromatography, respectively. From the Cumulative MWD, we calculated the fractions of LMWC with molecular weight (M): ≤2000, ≤5000, and ≤10,000 g/mol. Due to the low MW, the content of LMWC with M ≤1000 g/mol was determined by gas chromatography-mass spectrometry. The dynamic viscosity (η) was assessed by rotational rheometry. Results For all SilOils, the polymer was polydimethylsiloxane. The samples differed significantly in terms of MWD and relative LMWC fractions. Specifically, the relative fraction of all LMWC (M ≤10,000 g/mol) ranged from 2.31% to 9.40% and the content of LMWC with M ≤1000 g/mol also varied significantly (range, 51-1151 ppm). The η values were different between the SilOils, and, for many of them, from the declared viscosity. Conclusions Commercially available SilOils differ significantly in molecular and rheologic features. These compounds contain a significant amount of LMWC, "impurities" generated during the synthesis process, acting as emulsifier, potentially inducing ocular inflammation and toxicity. Translational relevance The amount of impurities in different SilOils may influence significantly their biocompatibility.

This paper reports on synthesis, acid-base properties and self-structuring in water of chiral polyamidoamino acids (PAACs) obtained by polyaddition of N,N&prime, methylenebisacrylamide with l-alanine, l-valine and l-leucine (M-l-Ala, M-l-Val, M-l-Leu) with potential for selective interactions with biomolecules. The polymers maintained the acid-base properties of amino acids. In water, the circular dichroism spectra of PAACs revealed pH-dependent structuring in the range 3&ndash, 11 and in the wavelength interval 200&ndash, 280 nm. Taking as reference the values at pH 3, the differential molar ellipticities were plotted in the pH interval 3&ndash, 11. Sigmoidal curves were obtained presenting inflection points at pH 8.1, 6.8 and 7.3 for M-l-Ala, M-l-Val and M-l-Leu, respectively, corresponding to the amine half-ionization. Theoretical modeling showed that PAACs assumed stable folded conformations. Intramolecular interactions led to transoid arrangements of the main chain reminiscent of protein hairpin motif. Oligomers with ten repeat units had simulated gyration radii consistent with the hydrodynamic radii obtained by dynamic light scattering.

By applying the enzyme catalase, our study on hyaluronan degradation confirms the generation of hydrogen peroxide using the Weissberger biogenic oxidative system (WBOS), which is composed of ascorbate and cupric ions. Dynamic viscosities of hyaluronan (HA) solutions influenced by WBOS in the absence and presence of catalase were analysed by rotational viscometry. Molar masses of HAs were determined by size-exclusion chromatography with multi-angle laser-light scattering. Our results show that catalase dose-dependently inhibited the degradation of HA macromolecules, which presumably confirms the generation of H2O2 in the reaction system. This has implications in range of biomedical applications such as arthritic joint treatment, tissue engineering, ocular and cosmetic surgery.

Soluble biobased lignin-like polymeric substances (SBO) isolated from the alkaline hydrolysates of composted biowastes are promising chemical auxiliaries for multiple uses. They have good surfactant properties. Their black color spoils their performance in detergency and dyeing. Ozonization of SBO is reported now to yield bleached biosurfactants with improved performance. The work was performed, with SBO obtained from composted gardening residues, alone or mixed with kitchen wastes. They were dissolved in water at 3.3 % concentration. Oxygen containing 4 mol/mol % ozone was flown at 60 L h−1 for 48 h through the SBO solution. The crude ozonized products in ca. 80 % yield were filtered through different molecular cut off membranes and characterized for chemical features, molecular weight, and surface tension in water. The ozonized fractions with 200–500 kDa molecular weights accounted for 12–29 % of the total ozonized fractions's organic matter. They lowered water surface tension to 48–52 mN m−1. The lower molecular weight ozonized fractions had no surfactant activity, but their molecular features suggest other potentially valuable uses.

Two homologous series of rod-coil block-copolymers, composed by a low band gap rod moiety (poly[2,6-(4,4-bis-(2-ethylhexyl)-4 H -cyclopenta[2,1- b :3.4- b’ ]dithiophene)- alt -4,7-(2,1,3-benzothiadiazole)], PCPDTBT) and a flexible poly(4-vinylpyridine) based polar block, were synthesized by two different approaches. Step Growth-like procedure provided copolymers with longer coil, whilst copolymers with longer rod arise from Chain Growth-like process. Both the series were deeply investigated with different analytical techniques ( 1 H NMR, SEC-DV, and MALDI-TOF MS) in order to prove the coupling process and elucidate the composition of the obtained materials. Chemical composition was evaluated by 1 H NMR analysis. DSC heating traces of rod-coil copolymers synthesized by Step Growth-like route present two well resolved glass transition temperatures corresponding to the rod and coil blocks. The low band-gap rod-coil block copolymers especially these with short coil can find application in hybrid solar cells.

The formulation of cost-effectiveness sustainable materials is extensively growing and becoming an attractive approach for both industrial and academic fields. In this context, the bio-based aliphatic polyamide 11 (PA11) has acquired significant interest as environmentally friendly thermoplastic option. In addition, its formulation with selected natural antioxidant and/or reinforced compounds through green processing methods, might improve physical and mechanical properties without sacrificing the intrinsic bio-based nature of the matrix. In this work, we have investigated and compared the photo oxidative degradation processes occurring on PA11 composites based on thymol and halloysite nano tubes prepared by using ball-milling method. In particular, halloysite nanotubes were used as green nano-container of a natural antioxidant molecule, and reinforced nano-filler as well. Molecular and structural information of photo-exposed samples were obtained by using size exclusion chromatography (SEC) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Thermal and mechanical properties were also tested as well as thymol release. Data collected confirmed that PA11 filled with HNTs-Thymol nano-hybrid showed superior durability performance if compared to both pure PA11 and PA11 blend realized by simply adding thymol and HNTs to polymer matrix. Furthermore, we found that HNTs and thymol combined in the nano-hydrid form exhibited an active and synergic role to achieve a major photo stabilization of PA11 biocomposite, without sacrificing its mechanical properties. (C) 2018 Elsevier Ltd. All rights reserved.

In order to develop a technology platform based on two natural compounds from biorenewable resources, a short series of hyaluronan (HA) copolymers grafted with propargylated ferulic acid (HA-FA-Pg) were designed and synthesized to show different grafting degree values and their optical properties were characterized in comparison with reference compounds containing the same ferulate fluorophore. Interestingly, these studies revealed that the ferulate fluorophore was quite sensitive to the restriction of intramolecular motion and its introduction into the rigid HA backbone, as in HA-FA-Pg graft copolymers, led to higher photoluminescence quantum yield values than those obtained with the isolated fluorophore. Thus, the propargyl groups of HA-FA-Pg derivatives were exploited in the coupling with oleic acid through a biocompatible nona(ethylene glycol) spacer as an example of the possible applications of this technology platform. The resulting HA-FA-NEG-OA materials showed self-assembling capabilities in aqueous environment. Furthermore, HA-FA-NEG-OA derivatives have been shown to interact with phospholipid bilayers both in liposomes and living cells, retaining their fluorogenic properties and showing a high degree of cytocompatibility and for this reason they were proposed as potential biocompatible self-assembled aggregates forming new materials for biomedical applications.

Spontaneous polymerization is an intriguing phenomenon in which pure monomers begin their polymerization without initiators or catalysts. Previously, 3-phenylbenzofulvene monomers were found to polymerize spontaneously after solvent removal. Here, eight new 3-substituted benzofulvene monomers 1a&ndash, h were synthesized in order to investigate the effects of differently substituted aromatic rings in position 3 of the benzofulvene scaffold on spontaneous polymerization. The newly synthesized monomers maintained the tendency toward spontaneous polymerization. However, monomer 1a, bearing an ortho-methoxy substituted phenyl, polymerized hardly, thus producing low polymerization yields, inhomogeneous structure, and low molecular weight of the obtained polymeric material. This result suggested the importance of the presence of hydrogen atoms in the 2&prime, position to achieve productive interactions among the monomers in the recognition step preluding the spontaneous polymerization and among the monomeric units in the polybenzofulvene backbones. Moreover, this study paves the way to modify the pendant rings in position 3 of the indene scaffold to synthesize new polybenzofulvene derivatives variously decorated.

The valorisation of bio-waste is pursued to cope with the increasing amount of waste that results from human food consumption and also to find renewable feedstock for manufacturing fuel and chemicals, as an alternative to fossils. Bio-waste is currently processed using fermentation and thermo-chemical technologies, to produce bio-fuel, compost and small platform molecules. Commercial low temperature chemical processes to valorise the bio-waste lignin fractions as feedstock for value-added chemicals do not as yet exist. The present work addresses this technology gap showing that the low-temperature hydrolysis of municipal bio-waste compost is a safe eco-friendly, cost effective process for converting the lignin-like material from compost into value-added speciality chemicals. It is reported that the process produces a 30%–70% yield of soluble biopolymers (SBO) as temperature increases from 60 to 150 °C. The SBO at 150 °C exhibit the best surfactant properties, making them promising for multipurpose uses in the future. The reaction yield is limited by non-hydrolysable lignin-like matter present in the pristine compost. Energy changes occur due to endothermic and exothermic reaction during hydrolysis at different temperatures. The process allows most of the process water and reagent to be recycled and saves on reagents, water and processing energy. No secondary treatment of the process effluent is necessary. The data lead to the conclusion that it will be feasible to produce SBO at commercial level through low-temperature hydrolysis of compost or biomass from different sources.

Trimethylammonium-2-hydroxypropyl-(TMAHP) spacer was introduced into heparin (H) and the prepared films were characterized by elemental analysis, NMR, SEC-MALS, TG/DTG/DTA, AFM and mechanical tester. When quaternized at the ratio of H/NaOH/alkylating agent/H2O = 0.1-1/0-2/0.1-1/50-500 mmol, H was substituted at A6 and A3 positions. The formation of double-substituted structures by substitution of free hydroxyl group of the previously introduced TMAHP substituent is evident. In the absence of NaOH (H/GTMAC/H2O = 1:1:500) the most drastic decrease of Mn to 8.639 kg/mol and Mw/Mn at 1.48 was observed in comparison to H (Mn = 9532 g/mol with Mw/Mn = 1.38). The film mechanical properties were better on H (E = 4030 MPa; σb = 65 MPa; ɛb = 4.6%) than on quaternized specimens (E = 2500–3340 MPa; σb = 25–40 MPa; ɛb = 1.7–1.8%). The AFM images did not prove relation between mechanical properties and surface shape.

Two new benzofulvene derivatives bearing a fluorene chromophore in different positions of the phenylindene scaffold were synthesized and induced to polymerize spontaneously. The photophysical investigation evidenced the role of the substitution topology of the monomeric units in the optical properties of the corresponding polymers. In particular, the polymer emission efficiency was found to improve both in solution and in the solid state when the fluorene residue enhances monomer conjugation and rigidity. The ability of this newly synthesized class of polymers to self-organize in supramolecular structures is evidenced through a study on blends with a benzothiadiazole based dye at different concentrations. Aggregation quenching processes of the dye are sharply reduced and complete resonant energy transfer from the polymer to the dye is reached even at 1% dye concentration. The peculiar ability of this new class of pi-stacked polymers to self-assemble in such a supramolecular organization suggests their use as platforms for the design of more complex nanostructured films with enhanced optical and optoelectronic properties.

A new polymer brush was synthesized by spontaneous polymerization of benzofulvene macromonomer 6-MOEG-9-T-BF3k bearing a nona(ethylene glycol) side chain linked to the 3-phenylindene scaffold by means of a triazole heterocycle. The polymer structure was studied by SEC-MALS, NMR spectroscopy, and MALDI-TOF MS techniques, and the results supported the role of oligomeric initiatory species in the spontaneous polymerization of polybenzofulvene derivatives. The aggregation features of high molecular weight poly-6-MOEG-9-T-BF3k-FE were investigated by pyrene fluorescence analysis, dynamic light scattering studies, and transmission electron microscopy, which suggested a tendency towards the formation of spherical objects showing dimensions in the range of 20&ndash, 200 nm. Moreover, poly-6-MOEG-9-T-BF3k-FE showed an interesting cytocompatibility in the whole concentration range tested that, besides its aggregation features, makes this polybenzofulvene brush a good polymer candidate for nanoencapsulation and delivery of drug molecules. Finally, the photo-physical features of poly-6-MOEG-9-T-BF3k-FE could allow the biodistribution of the resulting drug delivery systems to be monitored by fluorescence microscopy techniques.

Hyaluronic acid (HA) forms pericellular coats in many cell types that are involved in the early stages of cell adhesion by interacting with the CD44 receptor. Based on the largely recognized overexpression of the CD44 receptor in tumor tissues, a polybenzofulvene molecular brush has been enveloped into hyaluronan shells to obtain a tri-component polymer brush (TCPB) composed of intrinsically fluorescent backbones bearing nona(ethylene glycol) arms terminated with low molecular weight HA macromolecules. The nanoaggregates obtained in TCPB water dispersions were characterized on the basis of dimensions, zeta potential, and in vitro cell toxicity. This biomimetic multifunctional material bearing HA on the surface of its cylindrical brush architecture showed promising prerequisites for the preparation of nanostructured drug delivery systems.

Two homologous series of rod-coil b[lock copolymers, composed by a low band gap rod moiety (poly[2,6-(4,4 bis-(2ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b' ]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) anda flexible poly(4-vinylpyrydine) (P4VP) based polar block, were synthesized by two different approaches. Step Grwoth-like procedure provided copolymers with longer coil, whilst copolymers with longer rod arise from Chain Growth-like process. Both the series were deeply investigated with different analytical tecniques (1H NMR, SEC-DV, and MALDI-TOF MS) in order to prove the coupling process and elucidate of the obatined materials. Chemical composition was evaluated by 1H NMR analysis. DSC heating traces of rod-coil copolymers synthesized by Step Growth-like route present two well resolved glass transition temperatures corresponding to the rod and coil blocks. The low band-gap rod-coil copolymers especially these with short coil can find application in hybrid solar cells. The length of the coil block is strongly limited by the low reactivity of the macroiniziator related two the rigid ity of the conjugated systems with respect to the poly( 3-hexyl thiophene) (P3HT). The shortness of a coil segmente (P4VP) allows to perform a proper MALDI-TOF MS characterization which is in agreement with 1H-NMR data. A series of rod-coil copolymers was prepared with predominance of the rod block (>86%w) stating from a fixed ro block and tuning the length of the rod moiety, by varying both the Macroiniziator/4VP ratio and the time of the nitroxide mediated radical polymerization (NMRP). The two series of obtained materials aggregate indifferent manners and show ditinct organizations in solid stat films depending of the respective length of the two blocks in the copolymers, from globular micelle-like to lamellar segregation as highlighted by AFM images with the increasing of the length of the coil segment.

International audience; Water-soluble biopolymers (SBO) were isolated from the alkaline hydrolysate of two materials sampled from an urban waste treatment plant; that is, an anaerobic fermentation digestate and a compost. The digestate biopolymers contained more lipophilic and aliphatic C, and less acidic functional groups than the compost biopolymers. The SBO were blended with poly (vinyl alcohol-co-ethylene), hereinafter EVOH. The blends were extruded and characterized by FTIR spectroscopy, size exclusion chromatography (SEC)-multi angle static light scattering (MALS) analysis, and for their thermal, rheological, and mechanical properties. The blends behavior depended on the type of SBO and its relative content. Evidence was obtained for a condensation reaction occurring between the EVOH and SBO. The best results were obtained with the blends containing up to 10% SBO isolated from the biowaste anaerobic digestate. Compared with the neat EVOH, these blends exhibited lower melt viscosity and no significant or great difference in mechanical properties. The results on the extrudates, compared with those previously obtained on the same blends obtained by solvent casting, indicate that the blends properties depend strongly also on the processing technology.

Low band gap (LGB) polymers are characterized by a band gap below 2 eV, thus absorbing light with wavelengths longer than 620 nm.1 Their polymeric chains are constituted by the alternating electron-rich and electron-poor units. LGB were widely studied in last decades to improve the efficiency of organic photovoltaics (OPVs) due to a better overlap with the solar spectrum, leading to a maximum photon harvesting in the devices.2 Combining this intrinsic feature with the appealing capability of the block copolymers (BCPs) to nanosegregate, we obtained new rod-coil BCPs with a rigid segment constituted by a LBG polymer and a flexible one made up of poly-4vinylpyridine (P4VP) or a segmented poly(styrene-random-4-vynilpyridine). P4VP allows the interaction with commonly used acceptor materials for organic or hybrid PVs.3 Two strategies were applied to the preparation of the target polymers, combining a nitroxide-mediated radical polymerization and a Suzuki polycondensation. A step-growth like approach, consisting in the synthesis, purification, and characterization of the two blocks separately, that were then coupled through a further Suzuki reaction, and a chain-growth like method, constituted by the early synthesis of a properly activated rigid macroiniziator for the subsequent polymerization of the flexible block. The two pathways led to two series of materials differing particularly in controlling the coil block length. Due to the strong differences in chemical-physical properties of the two blocks, the purification and characterization procedures of the obtained materials have to be ad hoc tailored for a correct determination of their molecular structure, crossing the data from different techniques.4 These materials showed, together with their self-assembling capability, interesting features exploitable for photovoltaic applications. Some of the obtained materials were successfully employed as nanostructuring additive in hybrid solar cells, with inorganic semiconductor nanoparticles of CdSe, as acceptor.5 New trials are in progress for the realization of composites nanostructures with PCBM in aqueous medium, to be used as active layers in bulk heterojunctions solar cells. Preliminary results of these studies will be presented. Acknowledgments: research supported by Project AQUA-SOL - Aqueous processable polymer solar cells: from materials to photovoltaic modules (PRIN 2012A4Z2RY) 1 Bundgaard, Krebs, Solar En Mater & Solar Cells 91 (2007) 954. 2 Jayakannan, Van Hal, Janssen , J. Pol. Sci. A Pol. Chem 40 (2002) 251. 3 Di Mauro, Toscanini, Piovani, Samperi, Curri, Corricelli, Comparelli, Agostiano, Destri, Striccoli, Eur Pol J 72 (2014) 222. 4 Zappia, Mendichi, Battiato, Scavia, Mastria, Samperi, Destri, Polymer 80 (2015) 245; Samperi, Montaudo Battiato, Zappia, Destri, paper submitted. 5 Zappia, Destri, Striccoli, Curri, Di Mauro, Zoobia, Maruccio, Rizzo, Mastria, Adv. Sci. Technol. 93 (2014) 235; Zappia, Di Mauro, Mastria, Rizzo, Curri, Striccoli, Destri, accepted Eur. Pol J. (2016) doi:10.1016/j.eurpolymj.2016.03.021

As previous work proposed commercial expectations for soluble bio-organic substances (SBO) isolated from compost of urban food, gardening and park trimming residues as chemical auxiliaries, nine urban bio-wastes (BW) treated by aerobic and anaerobic digestion for 0-360 days were used to extract SBO and investigate source variability effects on product chemical composition and properties. The bio-wastes were collected over a 13732 km(2) area populated by 2.9 millions from 565 municipalities. The SBO were characterized by their content of different C types and functional groups and by their distribution coefficient (K(PEGW)) between polyethylene glycol and water. A significant linear correlation was found between KPEGW and the lipophilic/hydrophilic C ratio. The investigated SBO exhibited up to sixfold change of K(PEGW) demonstrating that BW available from densely populated urban areas are an interesting exploitable source of a wide variety of potential products for the chemical market. (C) 2010 Elsevier Ltd. All rights reserved.

Sugar beet pulp was extracted and chemically modified under acidic conditions using glycidyltrimethylammonium chloride in the presence of trifluoroacetic acid (TFA), HCl or H 3 PO 4 . The goal was to find out how the used acid and quaternization could affect the yield of soluble polysaccharide, its molar mass, monosaccharide composition, and structure. The use of HCl and H 3 PO 4 gave smaller yields of eluents when quaternized than in the presence of TFA at ambient pressure (10% of fraction over 10 kDa and 7% of a 1–10 kDa fraction). The monosaccharide composition analysis confirmed that the use of TFA for quaternization under vacuum resulted in fraction with the higher arabinose content (86%) than the use of HCl or H 3 PO 4 . The molar masses were similar as on analogical extracts obtained under alkaline conditions. The NMR data indicated that the arabinan structure is modified with the quaternary group at terminal C-5 of arabinofuranose unit.

The present article deals with the synthesis and characterization of some sulfonated copolyethersulfones. The synthetic approach differs from the post sulfonation approach traditionally reported in the literature. The synthetic procedure is based on the use of sulfonated monomers which are then reacted with previously synthesized telechelic hydoxy-ended poly (ether sulpnone)s. Combining the MALDI-TOF MS and 1H NMR analyses, with SEC-Viscometry and TGA measurements, we demonstrate a powerful tool for characterizing the chemical composition, end chains, degree of sulfonation (DS) and molecular mass distribution (MMD) of disulfonated poly(arylene ether-sulfone) copolymers. The characterization techniques allowed to determine the exact nature of the copolymers synthesized and to reveal some interesting features about the reaction. DMA data show that the glass transition temperature of sulfonated copolymers with similar DS increase as raise their MMD. Copolymers with a DS of 10–11 mol % reach a Tg of 244–246 °C. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3010–3023, 2010

Sugar beet pulp (SBP) was chemically modified with the goal to utilize this method for the preparation of water-soluble polysaccharides. Yields of the trimethylammoniumhydroxypropylated (TMAHP) polysaccharide fractions prepared under vacuum in absence of NaOH or KOH, as well as their molar masses, were higher than those obtained when the samples were only extracted with hydroxide at ambient pressure. The hydroxypropylsulfonated (HPS) fractions extracted at ambient pressure with NaOH had higher yields and molar mass than the TMAHP fractions extracted under vacuum with KOH. Introduction of both ion-exchange groups in one step under vacuum with NaOH gave better yields than with KOH, but smaller than for the solely sulfonated sample. The molar masses of chemically modified fractions were smaller than those extracted only with alkali or water. According to the monosaccharide composition all the fractions are mixtures of arabinogalactans and rhamnogalacturonoans.

A poly(amido-amine), PAA, bearing β-CD units in the side chain was synthesized by a polyaddition reaction of 1,4-bis-acryloyl-piperazine with 6-monodeoxy-6-monoamino-β-cyclodextrin (β-CD-NH2). Unlike the simple β-CD-NH2 with a greater basicity constant (log K = 8.60), the polymer revealed an unusual polyelectrolyte behaviour with a lower basicity constant (log K° = 6.29) of the tertiary nitrogen atom, that is strongly dependent on the degree of protonation α of the whole macromolecule. It follows the modified Henderson–Hasselbalch equation with n = 1.75, in a wide α-range. The greater (−46.1 kJ/mol) and the lower (−27.6 kJ/mol) enthalpy (ΔH°) changes of the compounds were in line with the protonation of a primary or a tertiary nitrogen atom. The calorimetric data suggested that the PAA protonation destroyed a packing structure formed by two rigid β-CD side chains interacting head-to-head. The UV spectrophotometric data showed that the PAA exhibits affinity towards the l-ascorbic acid at low pH (pH 2.46) with an isosbestic point at 241 nm and a slight blue shift of the maximum absorption of the ascorbic acid (244 nm) on PAA additions.

Poly-BF3a, a new hydrophobic polymer obtained by spontaneous polymerization of 1-methylene-3-phenyl-1H-indene, was found to give nanoparticles characterized by favorable shape and dimensions. Poly-BF3a nanoparticles were loaded with CR3124, a potent 5HT3 antagonist, as a drug model by desolvation methods either in the absence or in the presence of polyethylene glycol (PEG1000) as a wetting agent. The SEM studies showed that the introduction of CR3124 into the preparation led to a variable degree of aggregation–cementation, which afforded a sort of nanocomposite material. In the absence of PEG1000, the drug molecule was found to stay in the amorphous state (DSC studies) when its percentage is not higher than 10% by weight. In vitro release experiments showed that the formation and stability of the dispersion as well as the drug release were remarkably affected by the presence of PEG1000, demonstrating its beneficial effect to the nanoparticle morphology and disaggregation.

Molecular weight and size distributions of two glutenin polymers were determined by a multi-angle laser light scattering (MALLS) photometer on-line to a size exclusion chromatography (SEC) system. Two glutenin polymers extracted, sonicated and purified from wheat flours of different cultivars, i.e. Cheyenne and Chinese Spring, were accurately fractionated by SEC using three buffers (pH 2.6, 4.0 and 6.9) and two column sets. Both molecular weight distribution (MWD) and radius of gyration distribution (RGD) could be used to differentiate the two cultivars. MWD of glutenin polymers is a complex mixture of high- and low-molecular weight fractions and the relative percentage was found to be very different. The two cultivars were found to be different; in particular, the Chinese Spring polymer showed more compact conformation than the Cheyenne polymer. The slope of the conformation plot for glutenin was about 0.37, close to the theoretical value for compact spheres. Determination of glutenin MWD and RGD was difficult and depended on the buffer used and the SEC columns.

A simple chemo-enzymatic strategy for the synthesis of functionalized poly(1,5-dioxepane-2-one)esters has been developed. The protocol involves first the reaction of a primary amine with 1,5-dioxepane-2-one (2) to give an amide carrying a terminal primary hydroxyl group, followed by an enzymatic ring-opening polymerization catalyzed by Novozym 435. The proposed method is easy to handle and is suitable for the incorporation of different amines, as it has been shown with the model benzyl amine (3), the functionalized amines tyramine (4) and propargylamine (5), and the bioactive compound N-deacetylthiocolchicine (6).

Poly(arylenevinylene) polymers bearing fluorine atoms in the vinylene units were obtained by a Stille cross-coupling reaction of (E)-(1,2-difluoro-1,2-ethenediyl)bis(tributylstannane) with diiodoaryl derivatives. The introduction of fluorine atoms on the double bond of the stannane leads to polymers with relatively high molecular weights. Furthermore, the presence of fluorinated vinylene units changes the optical properties of the polymers and shifts the emission towards the blue region of the visible spectrum. A fluorinated analogue of MEH-PPV was obtained, and it shows photoluminescence that is considerably blueshifted, also in the solid state, relative to that found for nonfluorinated MEH-PPV and to other PPVs with fluorinated double bonds.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The polymerization of trans-diene BF1 [ethyl 1-methylene-3-(4-methylphenyl)-1H-indene-2-carboxylate] has been studied in the presence of various amounts of an anionic initiator such as phenyllithium in order to obtain information on the properties of this diene monomer and on its polymers. The anionic polymerization of BF1 produced a mixture of oligomers and a polymer (poly-BF1-AP), the proportion of which is regulated by the amount of the initiator used. Poly-BF1 was separated from lower oligomers on the basis of the solubility in n-hexane, and the soluble material was further fractionated by chromatography to obtain activated monomers and dimers. The structure of dimers and poly-BF1-AP has been investigated by NMR spectroscopy, absorption and emission spectroscopy, and mass spectrometry. The whole set of results is consistent, confirming for poly-BF1 a vinyl (1,2) polymer chaining stabilized by means of aromatic stacking interactions. The thermoreversibility of poly-BF1-AP was characterized by 1H NMR an...

The control of the organization of polymeric films from the nano- to the meso-scale is an ongoing field and different approaches have been proposed by many authors with the aim to drive the organization and the morphology of the materials to optimize their properties. One of the driving force of the organization at the micrometric and submicrometric scale is the degree of interaction between different polymeric chains and many successful examples of ordered supramolecular organization based on nano and microphase separation have been reported by using block copolymers and polymer blends. In this work we report on a synthetic approach to prepare a copolymeric structure formed by polystyrene and 3,4-ethylenedioxythiophene (EDOT) oligomers with the aim of preparing thin polymeric films exhibiting organized morphologies.