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There are many chemical analytical techniques available to probe molecular structures. Nuclear Magnetic Resonance (NMR) spectroscopy is an analytical spectroscopy technique that exploits strong external magnetic field and is capable of elucidating and quantifying molecular structures at the atomic level. NMR spectrum is typically measured from dissolved materials or directly from solid materials. The influence of magnetic interactions in solution and solid-state define the information that is obtainable from the NMR spectrum. The molecular motion and mobility play a key role. The obtainable spectral resolution in solid-state is usually lower than in the liquid state due to the presence of anisotropic interactions, which are not averaged out like in solution state. In NMR this means that the spectra, which contain the structural information, can be visually very different. These phenomena, combined with the need to obtain quantitative information, need to be addressed with proper considerations when acquiring and interpreting NMR data. This thesis focuses on the impact of relevant magnetic interactions in NMR via selected chemical structure studies of materials such as lignin, Ziegler-Natta (ZN) and aluminosilicate catalysts and cellulose. On olemassa useita kemiallisia analytiikka tekniikoita, joilla voidaan tutkia molekyylien atomitason rakenteita. Ydinmagneettinen resonanssispektroskopia (NMR) on analyyttinen spektroskooppinen tekniikka, joka hyödyntää voimakasta ulkopuolista magneettikenttää ja jolla voi tunnistaa ja määrittää molekyylien atomitason rakenteita ja määriä. NMR-spektri mitataan tyypillisesti liuotetusta tutkittavasta yhdisteestä, liuoksesta tai vaihtoehtoisesti myös suoraan kiinteästä materiaalista. Tutkittavien molekyylien magneettiset interaktiot määrittelevät pitkälti minkälaista informaatiota NMR-spektristä on mahdollista analysoida. Molekyylien liikkeellä on tässä asiassa suuri vaikutus. Saatavilla oleva NMR-spektrin resoluutio on tyypillisesti huonompi, jos NMR-spektri on mitattu kiinteästä materiaalista, kuin liuotetusta yhdisteestä. Tämä johtuu lähinnä anisotropiasta ja dipolaarisista kytkennöistä, joiden vaikutus liuostilan NMR-spektristä puuttuu. Käytännössä tämä näkyy siten, että liuostilan ja kiinteätilan NMR-spektrit voivat olla visuaalisesti hyvin erinäköisiä. Tämä spektrien fyysinen eroavaisuus yhdistettynä kvantitatiivisen atomitason tiedon määritykseen spektrin perusteella voi johtaa vääriin johtopäätöksiin. Tässä väitöskirjassa käsitellään magneettisten interaktioiden vaikutusta yleisesti NMR-spektroskopiassa ja NMR-rakennetutkimuksessa valikoitujen materiaalien (ligniini, Ziegler-Natta katalyytit, aluminosilikaatti katalyytit ja muokatut selluloosamolekyylit) avulla.

The objective of this study was to evaluate the ability of one versatile peroxidase and the biocatalytically generated complex Mn(III)-malonate to polymerize coniferyl alcohol (CA) to obtain dehydrogenation polymers (DHPs) and to characterize how closely the structures of the formed DHPs resemble native lignin. Hydrogen peroxide was used as oxidant and Mn2+ as mediator. Based on the yields of the polymerized product, it was concluded that the enzymatic reaction should be performed in aqueous solution without organic solvents at 4.5 ≤ pH ≤ 6.0 and with 0.75 ≤ H2 O2 :CA ratio ≤ 1. The results obtained from the Mn3+ -malonate-mediated polymerization showed that the yield was almost 100%. Reaction conditions had, however, effect on the structures of the formed DHPs, as detected by size exclusion chromatography and pyrolysis-GC/MS. It can be concluded that from the structural point of view, the optimal pH for DHP formation using the presently studied system was 3 or 4.5. Low H2 O2 /CA ratio was beneficial to avoid oxidative side reactions. However, the high frequency of β-β linkages in all cases points to dimer formation between monomeric CA rather than endwise polymerization. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:81-90, 2018.

A concept for direct surface modification on self-standing films of cellulose nanofibrils (CNF) is demonstrated using an aminosilane group in cellulose compatible solvent (dimethyl acetamide, DMA). The chemically modified structure efficiently prevents the oxygen molecules from interacting with the nanocellulose film in the presence of water molecules. Oxygen permeability values lower than 1 mL mm m-2 day-1 atm-1 were achieved at extremely high levels of relative humidity (RH95%). The aminosilane reaction is compared to conventional hydrophobization reaction using hexamethyldisilazane. The differences with respect to interactions between cellulosic nanofibrils, water and oxygen molecules taking place with aminated and silylated CNF films correlated with the degree of surface substitution, surface hydrophilicity and permeability of the formed layer. The self-condensation reactions taking place on the film surface during aminosilane-mediated bonding were decisive for low oxygen permeability. Experimental evidence on the importance of interfacial processes that hinder the water-cellulose interactions while keeping film's low affinity towards oxygen is demonstrated.

The objective of this study was to evaluate the ability of one versatile peroxidase and the biocatalytically generated complex Mn(III)-malonate to polymerize coniferyl alcohol (CA) to obtain dehydrogenation polymers (DHPs) and to characterize how closely the structures of the formed DHPs resemble native lignin. Hydrogen peroxide was used as oxidant and Mn

In this study surface-modified nanofibrillated cellulose (NFC) was used at low levels (0.5 to1.5 wt%) as a reinforcement in a polyvinyl alcohol (PVA) matrix. The modified-NFC-PVA composite films prepared using the solution casting technique showed improved mechanical performance. Birch pulp cellulose was initially modified by allylation using a solvent-free, dry modification method followed by subsequent epoxidation of the allyl groups and finally grinding the pulp to yield epoxy-NFC. In order to obtain optimal mechanical performance, epoxy-NFC with different degrees of substitution was evaluated in the reinforcement of PVA. The addition of 1 wt% epoxy- NFC (degree of substitution, DS 0.07) enhanced the modulus, strength, and strain of pure PVA film by 307, 139 and 23 %, respectively, thus producing the best performing film. The results demonstrate the favourable effect of chemically functionalized NFC on the mechanical properties of polyvinyl alcohol compared to unmodified NFC as reinforcement. In order to improve industrial and economic feasibility, the manufacture of the composite was also done in situ by grinding cellulose directly in PVA to produce the new biocomposite in a one-step process.

Chemical changes of lignin induced by the steam explosion (SE) process were elucidated. Wheat straw was studied as the raw material, and lignins were isolated by the enzymatic mild acidolysis lignin (EMAL) procedure before and after the SE treatment for analyses mainly by two-dimensional (2D) [heteronuclear single-quantum coherence (HSQC) and heteronuclear multiple-bond correlation (HMBC)] and 31P nuclear magnetic resonance (NMR). The β-O-4 structures were found to be homolytically cleaved, followed by recoupling to β-5 linkages. The homolytic cleavage/recoupling reactions were also studied by computational methods, which verified their thermodynamic feasibility. The presence of the tricin bound to wheat straw lignin was confirmed, and it was shown to participate in lignin reactions during the SE treatment. The preferred homolytic β-O-4 cleavage reaction was calculated to follow bond dissociation energies: G–O–G (guaiacyl) (69.7 kcal/mol) > G–O–S (syringyl) (68.4 kcal/mol) > G–O–T (tricin) (67.0 kcal/mol).

Chitosan–MAA nanoparticles (CS–MAA) with an average size of 10–70 nm were prepared by polymerizing chitosan with methacrylic acid in aqueous solution. The physicochemical properties of nanoparticles were investigated using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS) and nuclear magnetic resonance (NMR). The adsorption of Pb(II), Cd(II) and Ni(II) from aqueous solution on CS–MAA was studied in a batch system. The effects of the solution pH, initial metal concentration, contact time, and dosage of the adsorbent on the adsorption process were examined. The experimental data were analyzed using the pseudo-second-order kinetic equations and the Langmuir, Freundlich and Redlish–Peterson isotherms. The maximum adsorption capacity was 11.30, 1.84, and 0.87 mg/g for Pb(II), Cd(II) and Ni(II) ions, respectively, obtained by the Langmuir isotherm. However, the adsorption isotherm was better explained by the Freundlich rather than by the Langmuir model, as the high correlation coefficients (R2 > 0.99) were obtained at a higher confidence level.

In this study we have manufactured nanofibrillar cellulose and modified the fibre surface with ester groups in order to hydrophobise the surface. Nanofibrillated cellulose was chosen to demonstrate the phenomena, since due to its high surface area the effects at issue are pronounced. The prepared NFC ester derivatives were butyrate, hexanoate, benzoate, naphtoate, diphenyl acetate, stearate and palmitate. X-ray photoelectron spectroscopy, solid state NMR and contact angle measurements were used to demonstrate the chemical changes taking place on the cellulose surface. NFC ester derivatives can be prepared after a careful solvent exchange to a water-free solvent medium has been carried out. Butyl and palmitoyl esters were chosen for film forming tests due to the difference in their carbon chain lengths, and their contact angles and water vapour and oxygen permeation rates were studied. The prepared nanocellulose esters show increased hydrophobicity even at very low levels of substitution and readily form films when the films are prepared from acetone dispersions. The permeation rates suggest a potential use as barrier materials.

The preparation, characterization and application of a new stationary phase derived from 1,4-cyclohexanedione and diethyl (+)-tartrate are described. A suitable TADDOL for immobilization has been synthesized and grafted to a γ-mercaptopropylsilylated silica gel. The resulting modified stationary phase has been characterized and its ability to separate enantiomers has been studied. While the free TADDOL in solution was able to resolve a range of enantiomers, the resolving properties were lost on immobilization. Solid state 13C CPMAS NMR of the new stationary phase was used to explain the lack of stereoselective recognition.

Birch chips were cooked by means of the Lignofibre (LGF) organosolv process in acetic acid (AA) and phosphinic acid (H3PO2) at 150°C. The delignification rate and structure of the dissolved lignin was followed as a function of time. The degree of delignification increased steadily up to 88% during the 120 min treatment time. The dissolved lignins were precipitated from the spent liquor (SL) by water addition, washed, and purified for the analyses. Elemental analysis, 31P nuclear magnetic resonance (NMR), heteronuclear single-quantum coherence (HSQC) NMR, pyrolysis-gas chromatography/mass spectrometry (GC/MS), and gel permeation chromatography (GPC) were applied for the structural elucidation. It was found that the cleavage of the β-aryl ether linkages is the main reaction leading to delignification, accompanied by the formation of free phenolic hydroxyl groups and reduction in the content of aliphatic hydroxyl groups. The structure of the dissolved lignin remained the same after the drastic changes at the early stages of cooking (up to 30 min cooking time), indicating that secondary reactions (e.g., condensation) do not take place to a significant extent. H3PO2 probably enhances the acidolysis reaction via an ester derivative that both boosts the cleavage reaction and prevents the formation of the carbocation intermediate that induces condensation. Homolytic cleavage reactions may take place parallel to the acidolytic reactions.

Crude sulphate turpentine (CST), containing α-pinene, 3-carene, other terpene isomers, and organic sulphur compounds, was used as feedstock in the production of cymenes with commercial zeolite catalysts. The catalysts used were not sensitive to sulphur, and the desulphurisation step was not needed prior to cymene synthesis. The experiments were performed in a continuous fixed bed reactor. Promising results were obtained after initial optimization at temperatures close to 300 °C with faujasite Y zeolite under 5 bar N2 pressure. Cymenes were produced with 54% yields from model compound α-pinene and with 28% yields from CST. The mechanistic route of the reaction can be divided into three steps: (1) ring opening, (2) rearrangement, and (3) dehydrogenation. The final step in the formation of p-cymene can occur via dehydrogenation or disproportion; here the effect of reaction conditions and catalyst plays a crucial role.

The effect of lignin as an inhibitory biopolymer for the enzymatic hydrolysis of lignocellulosic biomass was studied; specially addressing the role of lignin in non-productive enzyme adsorption. Botanical origin and biomass pre-treatment give rise to differences in lignin structure and the effect of these differences on enzyme binding and inhibition were elucidated. Lignin was isolated from steam explosion (SE) pre-treated and non-treated spruce and wheat straw and used for the preparation of ultrathin films for enzyme binding studies. Binding of Trichoderma reesei Cel7A (CBHI) and the corresponding Cel7A-core, lacking the linker and the cellulose-binding domain, to the lignin films was monitored using a quartz crystal microbalance (QCM). SE pre-treatment altered the lignin structure, leading to increased enzyme adsorption. Thus, the positive effect of SE pre-treatment, opening the cell wall matrix to make polysaccharides more accessible, may be compromised by the structural changes of lignin that increase non-productive enzyme adsorption. © 2013 Elsevier Ltd.

Cellulose fiber has been modified by mechanical and chemical means in order to improve paper properties, which respond to moisture and temperature. When the cellulose is first refined and then etherified using hydroxypropylation under dry conditions, the paper sheets prepared from the hydroxypropylated cellulose show improved elongation. When the level of hydroxypropylation is high enough, the paper sheets also become transparent. Additionally, the effect of cellulose activation using different mechanical methods has been compared by esterification reactions. It is shown that removal of water is the most crucial step for the esterification reactions while other methods have a lesser impact. The paper sheets prepared from the esterified cellulose fibers show an increase in contact angles and high hydrophobicity.

In this study, solid state 13C NMR spectroscopy was utilised to characterize and identify the metal–ester coordination in active fourth generation (phthalate) Ziegler–Natta catalysts. It is known that different donors affect the active species in ZN catalysts. However, there is still limited data available of detailed molecular information how the donors and the active species are interplaying. One of the main goals of this work was to get better insight into the interactions of donor and active species. Based on the anisotropy tensor values (δ11, δ22, δ33) from low magic-angle spinning (MAS) 13C NMR spectra in combination with chemical shift anisotropy (CSA) calculations (δaniso and η), both the coordinative metal (Mg/Ti) and the symmetry of this interaction between metal and the internal donor in the active catalyst (MgCl2/TiCl4/electron donor) system could be identified.

Lignin is an inhibitory compound in the enzymatic hydrolysis of lignocellulosic feedstocks. Non-productive enzyme adsorption onto lignin and subsequent enzyme inactivation is a major inhibitory mechanism that increases the enzyme dosage and thus the costs, it also restricts enzyme recycling especially with softwood feedstocks. The underlying mechanisms causing non-productive enzyme adsorption have remained mostly unsolved. This paper describes interactions of the major Trichoderma reesei cellobiohydrolase Cel7A and itscatalytic core domain with well-characterized isolated lignins from different botanical origin, namely from spruce and wheat straw. Both non-treated and steam explosion (SE) pretreated lignocellulosic materials were used for lignin isolation and subsequent preparation of ultrathin lignin films for enzyme adsorption studies. We applied quartz crystal microbalance (QCM) technique for real-time monitoring of enzyme adsorption onto the different lignin films. Interestingly, more enzyme was bound onto the lignin films prepared of steam pretreated materials, whereas botanical origin of lignin had only a minor effect on enzyme binding.

The purpose of this work is to demonstrate how α-methylstyrene (AMS) can replace styrene in preparing styrene–butadiene (SB) type latexes and to compare the properties of the paper coating of the prepared α-methylstyrene–butadiene emulsion with the commercial styrene–butadiene latex reference sample. A lot of work is nowadays being conducted on different biorefinery concepts replacing fossil oil with biomass based raw materials due to the expected rise of the fossil oil cost. Aromatics can in principle be produced from renewable raw materials, such as lignin, sugars and terpenes for example. The potential methods include thermochemical conversions, catalytic fast pyrolysis, metabolic engineering, catalytic aromatisation and dehydrogenation among others. Terpenes, such as α-limonene and pinene, are possible sources of aromatics, and they can indeed be catalytically converted to p-cymene. Industrial hydrodealkylation and disproportionation processes developed by major petrochemical companies can further convert p-cymene to BTX aromatics or simultaneously dehydrogenate the alkyl chain of p-cymene to styrenic monomers such as α-methylstyrene. Based on the measured paper properties for uncalendered and calendered coated samples, AMS proved to be adequate to replace the oil based styrene in commercial reference SB latexes. Even though the emulsion polymerisation for the α-methylstyrene–butadiene latex was not optimised, almost all tested properties were at least equally good as in the commercial reference sample. α-Methylstyrene containing coating colours had slightly higher viscosity than the other coating colours. Coating colours containing α-methylstyrene seems to have an improved water retention compared to the commercial reference styrene–butadiene latex coating colour and the laboratory prepared styrene–butadiene coating colour. The paper coated with the commercial reference latex containing coating colour was less porous than the other coated papers. Despite of that, both dry and wet surface strength were at least equally good as in the case of the commercial reference latex. The results are promising when thinking of the future development of the bio-based latexes.

The present invention relates to a method for preparation a glycolide polyester by ring opening polymerization characterized in that glycolide monomer with optional co-monomer(s) of cyclic ester(s) is/are subjected to ring opening polymerization in the presence of a dispersion stabilizer and a catalyst, said catalyst being selected for precipitating glycolide homopolymer or copolymer from solvent, said solvent being selected so that the glycolide monomer and the optional co-monomer(s), the dispersion stabilizer and the catalyst are soluble therein but said glycolide homopolymer or copolymer is non-soluble. The present invention further relates to an in situ ring opening polymerizing process product, and to use of said glycolide polyester, and to further processing of said glycolide polyester.Patent family as of 30.9.2021DE602012027971 D1 20170309 DE201260027971T 20120523 EP2714768 A1 20140409 EP20120728300 20120523 EP2714768 B1 20170118 EP20120728300 20120523 FI20115504 A0 20110523 FI20110005504 20110523 US2014309366 AA 20141016 US20120123065 20120523 US9657147 BB 20170523 US20120123065 20120523 WO12160258 A1 20121129 WO2012FI50492 20120523Link to current patent family on right