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Funding The work leading to this article has been made in the ValBio-3D project funded by the Academy of Finland via the ERANet-LAC program, and partially in the FireCellCoat project funded by the Ministry of Agriculture and Forestry of Finland via the BIOECONOMY IN THE NORTH program. The work is a part of the Academy of Finland’s Flagship Programme under Projects No. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES). KSK acknowledges Academy of Finland project 310943 for funding. Oil-in-water emulsions stabilized using cellulose nanofibrils (CNF) form extremely stable and high-volume creaming layers which do not coalesce over extended periods of time. The stability is a result of the synergistic action of Pickering stabilization and the formation of a CNF percolation network in the continuous phase. The use of methyl cellulose (MC) as a co-emulsifier together with CNF further increases the viscosity of the system and is known to affect the droplet size distribution of the formed emulsion. Here, we utilize these highly stable creaming layer systems for in situ polymerization of styrene with the aim to prepare an emulsion-based dope for additive manufacturing. We show that the approach exploiting the creaming layer enables the effortless water removal yielding a paste-like material consisting of polystyrene beads decorated with CNF and MC. Further, we report comprehensive characterization that reveals the properties and the performance of the creaming layer. Solid-state NMR measurementsconfirmed the successful polymerization taking place inside the nanocellulosic network, and size exclusion chromatography revealed average molecular weight (Mw) of polystyrene as approximately 700,000 Da. Moreover, the amount of the leftover monomer was found to be less than 1% as detected by gas chromatography. The dry solids content of the paste was ∼20% which is a significant increase compared to the solids content of the original CNF dispersion (1.7 wt%). The shrinkage of the CNF, MC and polystyrene structures upon drying—an often-faced challenge—was found to be acceptable for this composite containing highly hygroscopic biobased materials. At best, the two dimensional shrinkage was no more than ca. 20% which is significantly lower than the shrinkage of pure CNF being as high as 50%. The paste, which is a composite of biobased materials and a synthetic polymer, was demonstrated in direct-ink-writing to print small objects. With further optimization of the formulation, we find the emulsion templating approach as a promising route to prepare composite materials.

The growth mechanism of Atomic Layer Deposition (ALD) on polymeric surfaces differs from growth on inorganic solid substrates, such as silicon wafer or glass. In this paper, we report the growth experiments of Al2O3 and ZnO on nonwoven poly-L-lactic acid (PLLA), polyethersulphone (PES) and cellulose acetate (CA) fibres. Material growth in both ALD and infiltration mode was studied. The structures were examined with a scanning electron microscope (SEM), scanning transmission electron microscope (STEM), attenuated total reflectance-fourier-transform infrared spectroscopy (ATR-FTIR) and 27Al nuclear magnetic resonance (NMR). Furthermore, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis were used to explore the effect of ALD deposition on the thermal properties of the CA polymer. According to the SEM, STEM and ATR-FTIR analysis, the growth of Al2O3 was more uniform than ZnO on each of the polymers studied. In addition, according to ATR-FTIR spectroscopy, the infiltration resulted in interactions between the polymers and the ALD precursors. Thermal analysis (TGA/DSC) revealed a slower depolymerization process and better thermal resistance upon heating both in ALD-coated and infiltrated fibres, more pronounced on the latter type of structures, as seen from smaller endothermic peaks on TA.

Oil-in-water emulsions stabilized using cellulose nanofibrils (CNF) form extremely stable and high-volume creaming layers which do not coalesce over extended periods of time. The stability is a result of the synergistic action of Pickering stabilization and the formation of a CNF percolation network in the continuous phase. The use of methyl cellulose (MC) as a co-emulsifier together with CNF further increases the viscosity of the system and is known to affect the droplet size distribution of the formed emulsion. Here, we utilize these highly stable creaming layer systems for in situ polymerization of styrene with the aim to prepare an emulsion-based dope for additive manufacturing. We show that the approach exploiting the creaming layer enables the effortless water removal yielding a paste-like material consisting of polystyrene beads decorated with CNF and MC. Further, we report comprehensive characterization that reveals the properties and the performance of the creaming layer. Solid-state NMR measurements confirmed the successful polymerization taking place inside the nanocellulosic network, and size exclusion chromatography revealed average molecular weight (Mw) of polystyrene as approximately 700,000 Da. Moreover, the amount of the leftover monomer was found to be less than 1% as detected by gas chromatography. The dry solids content of the paste was ∼20% which is a significant increase compared to the solids content of the original CNF dispersion (1.7 wt%). The shrinkage of the CNF, MC and polystyrene structures upon drying-an often-faced challenge-was found to be acceptable for this composite containing highly hygroscopic biobased materials. At best, the two dimensional shrinkage was no more than ca. 20% which is significantly lower than the shrinkage of pure CNF being as high as 50%. The paste, which is a composite of biobased materials and a synthetic polymer, was demonstrated in direct-ink-writing to print small objects. With further optimization of the formulation, we find the emulsion templating approach as a promising route to prepare composite materials.

International audience; Poultry feathers, a source of keratin, are a significant side stream from the food industry, for which valorization is essential considering the circular economy aspects. For this, ecofriendly processes are the tools that allow the easy and feasible transformation of the feathers. Deep eutectic solvents (DESs) are generally considered as inexpensive, relatively simple, mild and environmentally friendly solvents which can dissolve proteins from protein-rich biomasses. In this work, feathers were processed with an aqueous DES to produce a uniform keratin feedstock. The proposed DES is composed of non-toxic sodium acetate and urea, with a small amount of water. After the DES treatment, water was used to dilute the DES components and regenerate the dissolved keratin. The processing conditions were optimized in terms of keratin yield and properties by varying the dissolution time from 2 h to 24 h and temperature from 80 °C to 100 °C. The yield of regenerated keratin was followed at different sodium acetate–urea molar ratios, and compared to the treatment performed with choline chloride–urea or 8 M urea as reference solvents. Sodium acetate–urea in the molar ratio of 1 : 2 at 100 °C and with 6 h dissolution time dissolved 86% of the feathers with a regenerated keratin yield of 45%. In the characterization of regenerated keratin, it was found that when the dissolution temperature was higher and the dissolution time longer, the disulfide and total sulfur content of feather keratin decreased, the range of molecular weights became wider, and some of the ordered secondary structure and crystallinity were lost.

Electrospinning is a method that can be used in the production of polymeric nanofibres. Polymer solution is drawn into sub-µm to nanosized fibres utilizing electric field. The structure of electrospun web has intrinsic properties such as small fibre diameter, small pore size, and high specific surface area which are beneficial for various applications. In addition, fibres can be functionalized in various methods. Thin (nm scale), conformal coatings made by atomic layer deposition (ALD) can be used for functionalization. For example, metal oxides can provide interesting properties, such as electronic, antimicrobial, self-cleaning and hydrophobic properties among others, to fibrous materials. Combining electrospinning and thicker ALD layer enables also preparation of sub-µm tubes, if core fibres are removed. Aim of this work was to make electrospun fibres from three polymers, cellulose acetate (CA), polyether sulphone (PES) and poly-L-lactide (PLLA) to be used as substrates for ALD. In this presentation we will report preparation electrospun fibres using solvent mixtures, structure of electrospun sheets (PLLA shown as an example), and preliminary results of ALD carried out on electrospun sheets, as well as discuss the possibilities of ALD method in functionalization and processing of electrospun fibres.

The aim of this thesis was to combine several advanced nuclear magnetic resonance (NMR) spectroscopic techniques for studying the cellulose in materials still possessing, at least partly, the original complexity of wood fiber. The NMR spectroscopic approaches can be roughly divided into two classes: First, solid state NMR methods were used to characterize cellulose and its response to various treatments directly. This approach was used to characterize cellulose fibril aggregation in kraft pulps with different physical properties, and to characterize microcrystalline cellulose manufactured from various unconventional sources. Second approach involves utilization of molecular probes, namely solvent components and water, to provide information about interactions between solvent species and cellulose in pulp fibers, and about effect of certain reactivity enhancing pretreatments on cellulose accessibility and fiber wall structures up to micrometer size scale. The solvent molecules were studied during dissolution process using high resolution magic angle spinning (HR-MAS) NMR technique, which is capable of yielding a high resolution NMR spectrum from an inhomogeneous sample. Other approaches to observe the structural changes in pulp involved NMR diffusometry, studies of magnetization cross relaxation between water and cellulose, and quantitation of the amount of nonfreezing water in fiber wall using a proton NMR experiment. When comparing the different approaches, it was observed that the often used quantity, cellulose crystallinity, turned out to be a rather poor indicator for changes taking place in complex cellulose systems, as its value remained mostly inert while the other techniques already revealed changes in specific surface area of the fibers, average pore size at a size scale of ten nanometers, and in accessibility of chemicals through the fiber wall and to the cellulose fibrils. This shows the importance of combination of different type of NMR experiments when studying materials with considerable complexity. Tämän väitöskirjan aiheena on ydinmagnettiseen resonanssiin (nuclear magnetic resonance, NMR) perustuva spektroskopian hyödyntäminen selluloosapohjaisten materiaalien, kuten paperimassan ja mikrokiteisen selluloosan (MCC), rakennetutkimukseen. Lisäksi työssä tutkittiin NMR spektroskooppisin menetelmin puukuidun ja liuotinmolekyylien välisiä vuorovaikutuksia liuostusprosessin aikana sekä puukuidun liukoisuutta parantavien esikäsittelyiden (mekaaninen käsittely ja entsymaattinen hydrolyysi) vaikutusta kuidun rakenteeseen. NMR spektroskopia on yksi tärkeimmistä rakennetutkimusmenetelmistä kemiassa. Se antaa suoraa tietoa molekyylin funktionaalisista ryhmistä ja niiden keskinäisestä sijainnista molekyylissä, sekä molekyylin kolmiulotteisesta rakenteesta. NMR spektroskopian avulla pystytään myös tutkimaan kiinteiden materiaalien ominaisuuksia, kuten materiaalin kiteisyyttä ja kiteiden järjestäytymistä, olkoonkin että kiinteiden materiaalien tapauksessa spektrin erotuskyky ei yllä nestemäisten näytteiden tasolle. Tässä työssä kiinteän tilan NMR spektroskopiaa käytettiin karakterisoimaan selluloosan kiteisyydessä ja kiteiden muodostamien fibrillien pakkautumisessa tapahtuvia muutoksia. Toinen tässä työssä käytetty NMR spektroskooppinen lähestymistapa oli tutkia kuiturakennetta epäsuorasti havainnoimalla pienikokoisia kuituseinämän kanssa vuorovaikuttavia molekyylejä, kuten esimerkiksi nestetilaisia liuotinmolekyylejä sekä vettä. Tällöin on kuitenkin välttämätöntä turvautua erilaisiin erikoistekniikoihin, koska kuituseinämän epähomogeeninen rakenne estää korkean erotuskyvyn NMR spektrin mittaamisen. Selluloosan kiteisyys on parametri, jota käytetään usein karakterisoimaan selluloosamateriaaleja. Tämä väitöstyö kuitenkin osoittaa, että kiteisyys on vajavainen mittari selluloosapohjaisen materiaalin ominaisuuksien kuvaamisessa, ainakin sellaisten materiaalien tapauksessa joissa raaka-aineen rakenteen alkuperäinen monimutkaisuus on edelleen läsnä. Vaikka näytteiden kiteisyyksissä ei havaittukaan muutoksia, muut NMR spektroskooppiset menetelmät paljastivat muutoksia kuitujen ominaispinta-alassa, keskimääräisessä huokoskoossa sekä liuotinmolekyylien ja veden kyvyssä tunkeutua kuidun sisään. Eri NMR spektroskooppisten menetelmien käyttö yhdessä muiden analyysimenetelmien kanssa on täten välttämätöntä riittävän kokonaiskuvan luomiseksi materiaalin rakenteesta.

TIIVISTELMÄ Virtanen, Tommi 2014 Kehon Ikä-kartoituksen koetut vaikutukset elämänpolitiikkaan Liikuntakasvatuksen laitos Jyväskylän yliopisto Pro gradu tutkielma, 49s., 13s. liitteitä. ________________________________________ Monilla yrityksillä Tyky-päivät eivät enää keskity vain saunailtaan vaan terveys ja hyvinvointi ovat tulleet osaksi yrityksen toimintamallia. Tutkielmani on kytköksissä tähän tosiasiaan, että yksityisen sektorin hyvinvointipalvelut ovat lisääntyneet. Aiheeni on Kehon ikä-kartoituksen koetut vaikutukset yksilön elämänpolitiikkaan. Tutkielmassani esiintynyt hyvinvointipalvelu Kehon Ikä -kartoitus mahdollistaa kehon biologisen iän vertaamisen kronologiseen ikään. Tutkimusmenetelmänä käytin haastattelua, jonka avulla sain yksilön mielipiteitä Kehon Ikä-kartoituksesta ja sen vaikutuksista omassa elämässään. Tein myös kirjallisuuskatsauksen, jolloin kartoitin aiheeseen liittyvää aikaisempaa tutkimustietoa. Tein kahdeksan haastattelu ja analysoin ne, jonka jälkeen jäsensin tutkielmani tulokset ja rakensin omaa pohdintaani. Haastatellut kokivat Kehon Ikä-kartoituksen vaikuttaneen elämänpoliittisiin päätöksiin ja niiden sisältöihin. Näiden vaikuttavuuksien mittakaavassa kuitenkin oli selviä eroja, koska osa haastateltavista kokivat olevansa jo tietojen ja tekemisen osalta riittävällä tasolla, jotta olisivat kokeneet tarvetta muuttaa elämäntyyliään liikunnan tai ravitsemuksen osalta. Elämänpoliittisesti uskottiin nyt tehtyjen valintojen kestävän pitkälle tulevaisuuteen, koska esimerkiksi ravitsemukseen liittyvät muutokset ovat saaneet vaikutuksia aikaan jo lyhyellä aikavälillä, esimerkiksi vireystilan lisääntymisenä. Terveysihanteiden ja tavoitteiden asettelun osalta oli havaittavissa medikalisaation vaikutuksia, koska ne oli asetettu yleisesti hyväksyttyjen terveysihanteiden mukaisesti. Kuitenkaan tutkimuksessa ei ilmennyt nykytrendien, kuten karpaamisen tai muiden erityisruokavalioiden seuraamista. Tällöin voi otaksua, että mahdollisille elämäntapamuutokselle olisi eheä kasvualusta ja pysyvyyden kannalta tämä on optimaalinen lähtökohta. ABSTRACT Virtanen, Tommi 2014 Body Age mapping of the perceived impact of life policy Department of Sport Sciences University of Jyväskylä Master's thesis. 49pp., 13 appendicies. ________________________________________ Many companies working ability days are no longer only focus on sauna night and traditional entertainment, but the health and well being have become part of the company's operating model. This thesis is linked to the fact that the private sector health facilities have increased. My theme is the body's age mapping of the perceived effects of the individual life policy. The master's thesis appeared in welfare service Body Age mapping allows the body to the biological age of the comparison of chronological age. Interviews we used as the research method, those helped me to get deeper understanding of the individual's Body Age mapping and its impact on their lives. I also did a literature review in order to survey the previous research on the subject. I did eight interviews and the analysis of them, after which the structure result of the study, and I built our own reflection. The interviewees felt Body Age mapping influenced their life policy, decisions and their content, goal setting. However there were distinct differences, as some of the interviewees felt that they were already in the data and conclusion a sufficient level, so that would have felt the need to change the lifestyle of exercise and nutrition, such as an increase in alertness. Health ideals and objectives of the layout were visible effects of medicalization, as they were placed with generally accepted health ideals. However, the study did not show the current trends, such as low carbohydrate diet or other special diets to follow. In this case, you could expect that the potential lifestyle change would be a breeding ground and the stability of the whole; this is an optimal starting point.