The Oxyalkylation of Hydrophilic Black Alder Bark Extractives with Propylene Carbonate with a Focus on Green Polyols Synthesis

The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and lowtoxic base-catalyzed modification with propylene carbonate(PC).FTIR spectroscopy,HP-LC,GC,GPC,and wet chemistry methods were used to characterize the starting constituents,intermediate and final products of the reaction and to monitor the different pathways of PC conversion.The reaction of extractives as well as the model compounds,including catechol,xylose,PEG 400,and benzoic acid,with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC.The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain,obtained as a result of remaining PC homopolymerization.The domination of the oxypropylation mechanism vs.transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes,making the process of oxypropylation with PC similar to that of conventional oxypropylation.At optimal reaction conditions,including a PC/OH ratio of 3.0 and a 24-h duration at 150°C,uniform polyols with low viscosity of~900 mPa·s^(-1),a biomass content of~27%,and an OHV of~500 mg KOH·g^(-1) were obtained.Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity.At fixed temperature values,increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing.The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology.

Promotion of Ni/MCM-41 Catalyst for Hydrogenation of Naphthalene by co-Impregnation with Polyols

The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols （ethylene glycol, glycerol, xylitol, sorbitol and glucose）, were investigated by hydrogenation of naphthalene. Compared with the conventional wetness impregnation, addition of moderate polyols into the metal nitrate support surface, resulting in formation of persion of the active phase and significant aqueous solution could enhance interaction with very small NiO particle size （〈5 nm）, high discatalytic activity. Particle size of Ni^0 decreased from 36.1 nm to below 5 nm; meanwhile the complete hydrogenation of naphthalene was dependent on the Ni^0 particle size. The hydrogenation activities of the catalysts prepared by co-impregnation with polyols were very high with 100% conversion even at iow temperature of 55 ℃.

Ehealth monitoring in irritable bowel syndrome patients treated with low fermentable oligo-, di-, mono-saccharides and polyols diet

In the present study we report on changes in irritable bowel syndrome-severity scoring system (IBS-SSS) and irritable bowel syndrome-quality of life (IBS-QoL) in 19 IBS patients, aged 18 to 74 years (F/M: 14/5), during 12 wk registering their symptoms on the web-application (www.ibs.constant-care.dk). During a control period of the first 6-wk patients were asked to register their IBS-SSS and IBS-QoL on the web-application weekly without receiving any intervention. Thereafter, low fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet (LFD) was introduced for the next 6 wk while continuing the registration. Though a small sample size a significant improvement in disease activity (IBS-SSS) was observed during both the control period, median: 278 (range: 122-377), P = 0.02, and subsequently during the LFD period, median: 151 (range: 29-334), P < 0.01. The IBS-QoL solely changed significantly during the LFD period, median: 67 (37-120), P < 0.01. The significant reduction in disease activity during the control period shows a positive effect of the web-application on IBS symptoms when presented as a “traffic light”. However adding the diet reduced IBS-SSS to < 150, inactive to mild symptoms. In the future results from larger scale trials are awaited.

Preparation and characterization of tung oil-based flame retardant polyols

Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycerol by sodium methoxide. The products after transesterification were epoxidized by peracetic acid which was in-situ generated from acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst. And then, TOFPs were prepared from epoxidized alcoholysis tung oil(EGTO) with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO), diethyl phosphate(DEP) and diethanolamine(DEA) by ring-opening reactions, respectively. GPC was used to evaluate the conversion rate, at optimum reaction conditions, selectivity for monoglyceride in transesterification. The influence of different parameters such as temperature, mole ratio or mass ratio on the conversion rate of transesterification and epoxidation were investigated. The molecular structures of TOFPs were characterized by FTIR and ~1HNMR. Finally, tung oil-based polyurethane foams(TOPUFs) were prepared by a one-shot process using TOFPs with polyisocyanate. The LOI values of TOPUFs whose content of DOPO-EGTO,DEP-EGTO and DEA-EGTO were 100 wt% can reach to 26.2%, 25.1%, and 24.4%, respectively.

Self-reducing bifunctional Ni-W/SBA-15 catalyst for cellulose hydrogenolysis to low carbon polyols

A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized using biomass-based carbon source as the reducing agent without conventional further reduction step. The self-reducing catalysts were performed on the hydrogenolysis of cellulose to low carbon polyols. The effects of calcination temperature and metallic loading contents for cellulose hydrogenolysis reaction were investigated detailedly.The optimal calcination temperature was found to be 673 K by TG analysis. The active metal nanoparticles with a better dispersion were observed using SEM and element mapping technology. The yield of low carbon polyols using the catalyst with the receipt of 10%Ni-15%W/SBA-15-673 K can reach as high as68.14%, of which the ethylene glycol(EG) accounts for 61.04%.

Directional assist (0 1 0) plane growth in LiMnPO_(4) prepared by solvothermal method with polyols to enhance electrochemical performance

Phosphate material LiMnPO4 is popular for its high energy density(697 W·h·kg^(-1))and safety.When LiMnPO_(4) crystal grows,the potential barrier along b and c axis is strong,which makes the crystal grow along b axis to form a one-dimensional chain structure.However,the main migration channel of lithium ions in olivine structure is plane(010).By shortening the growth in the direction of b axis and enhancing the diffusion along the directions of a and c,two-dimensional nanosheets that are more conducive to the migration of lithium ions are formed.The dosage of polyols is the key factor guiding the dispersion of the crystals to the(010)plane.X-ray diffraction(XRD),Scanning electron microscopy(SEM),transmission electron microscopy(TEM)and other means are used to characterize the samples.After experiments,we found that when the ratio of polyol/water was 2:1,the morphology of the synthesized sample was 20–30 nm thick nanosheets,which had the best electrochemical performance.At 0.1C,the discharge specific capacity reaches 148.9 mA·h·g^(-1),still reaches 144.3 mA·h·g^(-1) at the 50th cycle.and there is still 112.5 mA·h·g^(-1) under high rate(5C).This is thanks to the good dispersion of the material in the direction of the crystal plane(010).This can solve the problem of low conductivity and ionic mobility of phosphate materials.

Catalytic Conversion of Biomass-Derived Polyols into Para-xylene over SiO2-Modified Zeolites

This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts.

Catalytic conversion of glucose to small polyols over a binary catalyst of vanadium modified beta zeolite and Ru/C

Catalytic conversion of glucose, the most abundant carbohydrate, to chemicals of petroleum origin has great desirability in terms of sustainability and industrial implementation. In this work, we attempted to exploit the vanadium-based catalysts with high retro-aldol condensation(RAC) activity for the synthesis of small polyols from glucose. Vanadium species incorporated or anchored beta zeolites were found to work effectively in synergy with 1 Ru/AC to produce hydroxyacetone(HA) as the major product(34%)in a semi-continuously stirred tank reactor under 5% glucose concentration. Catalyst characterization by UV-vis and Raman spectral analysis revealed vanadium species mainly stayed in the incorporated form(tetrahedral) at 0.5% of loading and in the supported form(octahedral) at higher loadings up to 8%. Pyridine infrared spectra and temperature programmed desorption of NH3 revealed weak Lewis acid sites in dominance. Vanadium species in the catalysts displayed multiple catalytic roles(isomerization and RAC reaction, and synergism with the hydrogenation catalyst) in the synthesis of HA from glucose. Structureactivity correlation pointed out that the catalytic activity of vanadium species is not dependent on it coordination status, nevertheless, the adjacent vanadium atoms could possibly improve the isomerization rate over the RAC rate in favor of high yield of HA. The catalyst system is recyclable to at least five times without any considerable loss in its activity and structural integrity. The results presented here provide a promising route for the sustainable production of HA and polyols from carbohydrates by using a highly selective vanadium catalyst.

Physico-mechanical characterization of polyurethane foam dressings containing natural polyols

Advanced wound dressings are replaced traditional dressings in order to provide appropriate environment for healing and also to promote cell migration[1].The key characteristics of wound dressings are non-toxic,highly absorbed,air permeable,biocompatible and have good mechanical properties[2].Due to providing moist environment and also protecting maceration at the wound edge area,foam dressings are used in various clinical applications[3].They are mostly prepared from polyurethane between polyols and isocyanate polymerization.

Surface Functionalization of Microporous Polypropylene Membrane with Polyols for Removal of Boron Acid from Aqueous Solution

Affinity membranes are fabricated for boric acid removal by the surface functionalization of microporous polypropylene membrane(MPPM)with lactose-based polyols.The affinity is based on specific complexation between boric acid and saccharide polyols.A photoinduced grafting-chemical reaction sequence was used to prepare these affinity membranes.Poly(2-aminoethyl methacrylate hydrochloride)[poly(AEMA)]was grafted on the surfaces of MPPM by UV-induced graft polymerization.Grafting in the membrane pores was visualized by dying the cross-section of poly(AEMA)-grafted MPPM with fluorescein disodium and imaging with confocal laser scanning microscopy.It is concluded that lactose ligands can be covalently immobilized on the external surface and in the pores by the subsequent coupling of poly(AEMA)with lactobionic acid(LA).Physical and chemical properties of the affinity membranes were characterized by field emission scanning electron microscopy and Fourier Transform Infrared/Attenuated Total Refraction spectroscopy(FT-IR/ATR).3-Aminophenyl boric acid(3-APBA)was removed from aqueous solution by a single piece of lactose-functionalized MPPM in a dynamic filtration system.The results show that the 3-APBA removal reaches an optimal efficiency(39.5%)under the alkaline condition(pH9.1),which can be improved by increasing the immobilization density of LA.Regeneration of these affinity membranes can be easily realized through acid-base washing because the complexation of boric acid and saccharide polyol is reversible.

Low fermentable oligosaccharides, disaccharides,monosaccharides, and polyols diet in children

Irritable bowel syndrome (IBS) is a lifelong condition with a high prevalence among children and adults. As the diet is a frequent factor that triggers the symptoms, it has been assumed that by avoiding the consumption of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP), the symptoms might be improved. Therefore, in the past decade, low FODMAP diet has been intensively investigated in the management of IBS. The capacity of FODMAPs to trigger the symptoms in patients with IBS was related to the stimulation of mechanoreceptors in the small and large intestine. This stimulation appears as a response to a combination of increased luminal water (the osmotic effect) and the release of gases (carbon dioxide and hydrogen) due to the fermentation of oligosaccharides and malabsorption of fructose, lactose and polyols. Numerous studies have been published regarding the efficacy of a low FODMAP diet compared to a traditional diet in releasing the IBS symptoms in adults, but there are only a few studies in the juvenile population. The aim of this review is to analyze the current data on both low FODMAP diet in children with IBS and the effects on their nutritional status and physiological development, given the fact that it is a restrictive diet.

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene glycol.For such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous solutions.Ethylene glycol,1,2-propanediol,and especially 1,2,5-pentanetriol were obtained with selectivities of 15%,14% and 22%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer solution.These preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

Functionalized Hyperbranched Aliphatic Polyester Polyols: Synthesis,Properties and Applications

Recently, hyperbranched polymers(HBPs), which differ significantly in structure and properties from linear, cross-linked and branched analogs, have become increasingly important. HBP have a spatial unloaded core and a shell of branched monomer units(dendrons), in which functional groups are predominantly located in the surface layer. The size of macromolecules ranges from 2 nm to 100 nm. Currently, there are a fairly large number of publications in the literature devoted to the modification of hyperbranched polyester polyols with various functional groups and the assessment of the potential for their use. However, there are no review articles on this topic in recent years. In this regard, it is relevant to generalize the latest achievements in the field of synthesis, properties and application of hyperbranched polyester polyols with terminal oxygen, nitrogen, silicon, sulfur and organophosphorus fragments. The advantage of hyperbranched polyester polyols of the Boltorn H series is their industrial availability, biodegradability, nanoscale, non-toxicity and high solubility in various polar solvents due to short monomer units, as well as the presence of reactive terminal hydroxyl groups. Functionalization of hyperbranched polyester polyols at hydroxyl groups is mainly carried out by addition of acid anhydrides, iso(thio)cyanates, alkenes, lactides, lactones, lactams, epoxy compounds or reactions with halogenated compounds(alkyl halides, acid chlorides). In some cases, for the functionalization of polyester polyols special linkers are used, such as acid chlorides of unsaturated or dicarboxylic acids, diisocyanates, etc., which provide covalent bonding of the hyperbranched polymer with the target functional group. The obtained derivatives of hyperbranched polyesters are widely used in such areas as biomedicine, pharmacy, paints and varnishes, they are also used as catalysts, membranes, multifunctional coatings, plasticizers and polymer stabilizers.

Tunable synthesis of furfurylamines orβ-amino alcohols via Ru-catalyzed N–H functionalization using biomass-derived polyols

We report the highly efficient conversion of readily available biomass-derived polyols with amines to valuable furfurylamines orβ-amino alcohols compounds using ruthenium catalysis.The reaction outcome is readily tuned by the simple addition of 4Åmolecular sieves(furfurylamines vs.β-amino alcohols)with high chemo-selectivity.The proposed reaction mechanism involves ruthenium-catalyzed hydrogen borrowing for the reduction of the imine intermediate and C–C bond cleavage of polyols via a retro-aldol process.A series of arylamines was suc-cessfully transformed into the desired products with moderate to good yields.

A facile convergent route to dendritic polyols

The synthesis of monodisperse dendrimers triggers a great challenge to the synthetic chemistry. Here, we reported a facile convergent approach to the synthesis of the first generation, six-directional ether-bond polyols with better controlled structures and ease of purification.

Polyurethane-based Actuators with Various Polyols

This study dealt with the electrostrictive responses of polyurethane （PU） actuators with different microphase separation structure, which was a promising candidate for a material used in polymer actuators. In order to construct PUs with different higher-order structure, PUs with various types of polyol were synthesized： poly（neopentyl glycol adipate） （PNAD）, poly（tetramethylene glycol） （PTMG）, and poly（dimethyl siloxnae） （PDMS）. Synthesized PU was characterized by Fourier transform-infrared （FT-IR） spectroscopy and gel per- meation chromatography （GPC）. Thermal analysis and mechanical properties of PU films were carried out with differential scanning calorimetry （DSC） and UTM （universal testing machine）, respectively. And PU actuator was formed in a type of monomorph, which was made by carbon black electrodes on the both surfaces of PU film by spin coating method. Actuation behavior was mainly influenced on microphase separation struc- ture and mechanical property of PU. In result, PU actuator with PNAD, polyester urethane, had the largest field-induced displacement.

Promoting role of Ru species on Ir-Fe/BN catalyst in 1,2-diols hydrogenolysis to secondary alcohols

Noble metal-based-bimetallic catalysts have been highly investigated and applied in wide applications including biomass transformation via regioselective C−O hydrogenolysis while further modification especially with noble metal is highly promising yet still under investigation.Herein,Ru was found as an effective modifier among the screened noble metals(Ru,Pt,Rh,Pd,Au,and Ag)for Ir-Fe/BN(Ir=5 wt%,Fe/Ir=0.25)catalyst in terminal C−O hydrogenolysis of 1,2-butanediol(1,2-BuD)to 2-butanol(2-BuOH).Only trace amount of Ru(up to 0.5 wt%)was effective in terms of high 2-BuOH selectivity(>60%)and activity(about twice).Larger amount of Ru species(3 wt%)highly enhanced the activity but gave low selectivity to 2-BuOH with by-products of terminal C−C bond scission.Optimized catalyst(Ru(0.5)-Ir-Fe/BN)was reusable at least 4 times and gave moderate 2-BuOH yield(47%)in hydrogenolysis of 1,2-BuD.The promoting effect of Ru addition(0.5 wt%)to Ir-Fe/BN on hydrogenolysis of various alcohols was also confirmed.Combining catalytic tests with various characterizations,the promotion mechanism of Ru species in trimetallic catalysts was clarified.The Ru species in Ru(0.5)-Ir-Fe/BN form alloy with Ir and are enriched at the interface with BN surface,and direct interaction between Ru and Fe was not necessary in Ru-Ir-Fe alloy.The interface of Ir and Fe on the surface of Ir-Fe alloy may work as active sites for 1,2-diols to secondary alcohols via direct C−O hydrogenolysis,in which Ru-modified Ir activates H_(2) to form hydride-like species.The activity of Ru species in C−C bond cleavage was highly suppressed due to the direct interaction with Ir species and less exposed to substrate.Larger loading amount of Ru species(3 wt%)led to the formation Ru-rich trimetallic alloy,which further works as active sites for C−C bond scission.

Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering

The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin nano-particles.For this purpose,the prepared coatings were applied to pine wood surfaces and weathered artificially.Subsequently,color and gloss of the coatings were measured before and after the weathering test.Field emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 nm.Nuclear magnetic resonance(13C-NMR)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based polyurethane.Differential calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in gloss.The lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane coatings.After weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°).

Diet therapy for inflammatory bowel diseases: The established and the new

Although patients with inflammatory bowel diseases(IBD) have a strong interest in dietary modifications as part of their therapeutic management, dietary advice plays only a minor part in published guidelines. The scientific literature shows that dietary factors might influence the risk of developing IBD, that dysbiosis induced by nutrition contributes to the pathogenesis of IBD, and that diet may serve as a symptomatic treatment for irritable bowel syndrome-like symptoms in IBD. The role of nutrition in IBD is underscored by the effect of various dietary therapies. In paediatric patients with Crohn's disease(CD) enteral nutrition(EN) reaches remission rates similar to steroids. In adult patients, however, EN is inferior to corticosteroids. EN is not effective in ulcerative colitis(UC). Total parenteral nutrition in IBD is not superior to steroids or EN. The use of specific probiotics in patients with IBD can be recommended only in special clinical situations. There is no evidence for efficacy of probiotics in CD. By contrast, studies in UC have shown a beneficial effect in selected patients. For patients with pouchitis, antibiotic treatment followed by probiotics, like VSL#3 or Lactobacillus GG, is effective. When probiotics are used, the risk of bacterial translocation and subsequent bacteremia has to be considered. More understanding of the normal intestinal microflora, and better characterization of probiotic strains at the phenotypic and genomic levels is needed as well as clarification of the mechanisms of action in different clinical settings. A FODMAP reduced diet may improve symptoms in IBD.

Diet and functional dyspepsia: Clinical correlates and therapeutic perspectives

Hypervigilance and symptoms anticipation,visceral hypersensitivity and gastroduodenal sensorimotor abnormalities account for the varied clinical presentation of functional dyspepsia(FD)patients.Many patients recognize meals as the main triggering factor;thus,dietary manipulations often represent the first-line management strategy in this cohort of patients.Nonetheless,scarce quality evidence has been produced regarding the relationship between specific foods and/or macronutrients and the onset of FD symptoms,resulting in nonstandardized nutritional approaches.Most dietary advises are indeed empirical and often lead to exclusion diets,reinforcing in patients the perception of“being intolerant”to food and self-perpetuating some of the very mechanisms underlying dyspepsia physiopathology(i.e.,hypervigilance and symptom anticipation).Clinicians are often uncertain regarding the contribution of specific foods to dyspepsia physiopathology and dedicated professionals(i.e.,dietitians)are only available in tertiary referral settings.This in turn,can result in nutritionally unbalanced diets and could even encourage restrictive eating behaviors in severe dyspepsia.In this review,we aim at evaluating the relationship between dietary habits,macronutrients and specific foods in determining FD symptoms.We will provide an overview of the evidence-based nutritional approach that should be pursued in these patients,providing clinicians with a valuable tool in standardizing nutritional advises and discouraging patients from engaging into indiscriminate food exclusions.