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The research work presents a new design of compression hosiery where compression around a human limb is generated using special air bladders. The pressure inside the air bladders is adjustable. The objective of the research was to study graduated compression and its control on the limb using the prototype with air bladders and two commercial compression products. The compression forces were measured around the limb under a knee in three sectors: a foot, a middle part and an upper part of the leg. Measurements were mainly done in vivo using the limb of a test person – although some pre-trials were done in vitro. During the tests it was concluded that the exact control of the compression was very difficult to achieve due to, for example, the shape and the composition of the limb. Based on the results, the compression values were unstable under the sectors and the graduated compression was nonlinear in the vertical direction for every tested hosiery. There is some analogy concerning the pressure distribution reported about standard mechanical compression hosiery. The results prove that our prototype enables one to achieve very high compression values in seconds, and to manage and to adjust instantly the compression rate in each sector. Efficient controllability and comfort are important matters in the medical treatment, where a patient wears the hosieries for prolonged times.

The introduction of a three dimensional scaffold providing the closest analogies to extracellular matrix (ECM) is currently a key strategy for tackling many challenges in tissue repair. Here, we present a new hybrid scaffold constructed by coating electrospun chitosan/polyethylene oxide (PEO) nanofibers on commercial BioTek polystyrene (PS) scaffold obtained from Sigma Aldrich. The viability and proliferation rate of mesenchymal stem cells (MSCs) seeded on micro-nano structured hybrid scaffold (MNHS) and commercial PS scaffolds were analyzed by MTT assay. The results of the MTT assay revealed a higher degree of viability and proliferation rate in MSCs seeded on MNHS compared with the commercial PS scaffold. DAPI images also confirmed the higher degree of attachment and viability of MSCs seeded on MNHS. Moreover, MSCs on both scaffolds differentiated to osteoblasts and adipocytes cells, as reflected by the images obtained from Alizarin Red and Oil Red-O staining. Alkaline phosphatase activity (ALP) and calcium content assays revealed that the MNHS has a higher potential for osteogenic differentiation than the commercial scaffold. To quantify the osteoblast and adipocyte gene expression, quantitative RT-PCR was carried out for MNHS, commercial scaffold and Tissue culture polystyrene (TCPS). It was found that MNHS can express a higher level of Runt-related transcription factor 2 (Runx2), osteonectin and osteocalcin in osteogenic differentiation as well as increased expression of PPAR? and UCP-1 in adipogenic differentiation. The enhancement of the attachment, viability and proliferation as well as bi-lineage differentiation may result from the biochemical and structural analogies of MNHS to native ECM. Furthermore, it was observed that biocompatible MNHS scaffold can potentially be utilized as a suitable scaffold for bone and connective tissue engineering.

The rapid coagulation of NaOH-based cellulose solution during the wet spinning process leads to a low stretching ratio and, consequently, the low mechanical properties of the fibres. The aim of this work was to slow down the coagulation by replacing the sulphuric acid spin bath with an acetic acid bath. The spin dope was prepared by dissolving the enzyme-treated dissolving pulp in aqueous sodium zincate using a freezing-thawing method. The optimal zinc oxide and sodium hydroxide concentrations were studied first. The most thermally stable cellulose solution contained 6.5 wt% NaOH and 1.3 wt% ZnO with 6 wt% enzyme-treated dissolving pulp. The spin dope was prepared accordingly. Coagulation of the cellulose solution slowed down in the acetic acid bath, resulting in a significantly higher stretching ratio for the fibres than with the sulphuric acid bath. However, the acetic acid spun fibres shrunk strongly during drying, and the possibly aligned order of the molecular chains due to the high stretch was partly lost. As a consequence, the high stretch was not transferred to high tenacity of the fibres in this study. However, the result suggests attractive potential to develop processing conditions to increase fibre tenacity.

The aim of this study was to regenerate fibres from the alkaline cellulose solution containing 3-allyloxy-2-hydroxypropyl substituents. Enzyme-treated cellulose was modified in alkaline aqueous tert-butanol (tBuOH) using allyl glycidyl ether (AGE) as the modification reagent. 3-allyloxy-2-hydroxypropyl substituted (AHP) enzyme-treated cellulose with DSA 0.05 was obtained. Enzyme-treated cellulose without (reference) and with substituents were dissolved in sodium zincate using the freezing-thawing cycle. The reference solution alone and the mixture solutions containing 10 or 25 % of the AHP cellulose were regenerated into cellulosic fibres using the wet spinning technique. The solutions containing 100 or 50 % of the AHP cellulose did not form fibres in acidic bath. The 10 % share of AHP cellulose did not affect the mechanical properties of the fibres (1.5 cN dtex-1), while the 25 % share decreased the tenacity slightly (1.3 cN dtex-1). Elongation of the fibres ranged from 18 to 22 %. The 10 and 25 % shares of AHP cellulose increased the water holding ability of fibres by 12 and 33 %, respectively. According to FESEM the fibre structures are composed of nanosized fibrils.

This paper examines the thermal and mechanical behaviour as well as moisture absorption of aligned hemp composites using hemp/PLA wrap spun yarns. Uniaxial composites were fabricated with 30 mass% hemp using compression moulding. The properties of composites in terms of hemp fibre orientation (aligned and random), off-axis angle and alkali treatment were investigated. It was found that the testing direction influenced the mechanical properties of the composites. Compared with all the fabricated composites, the aligned alkali hemp/PLA yarn composite possessed the best mechanical properties, including tensile, flexural and impact strengths, lower porosity and water absorption. The water absorption for all composites was higher than for neat PLA, both at room temperature and 80 °C. The PLA in its treated composites had higher crystallinity, which was attributed to effective heterogeneous nucleation induced by hemp. Based on SEM observation and theoretical analysis of DMTA data, there was a favourable interfacial adhesion in all composites.

A process for producing microfibrillated cellulose comprises providing a slurry comprising cellulosic fibers, treating the slurry with an enzyme, mechanically treating the slurry so that the fibers are disintegrated wherein the mechanical treatment and the treatment with the enzyme is performed simultaneously in a single treatment step. In this way it is possible to produce microfibrillated cellulose (MFC) in an improved and energy efficient way. A microfibrillated cellulose is produced according to the process.Patent family as of 4.4.2022AU2010269896 AA 20120209 AU20100269896 20100623 AU2010269896 BB 20150917 AU20100269896 20100623 AU2010269912 AA 20120209 AU20100269912 20100702 AU2010269912 BB 20160114 AU20100269912 20100702 BR112012000142 A2 20201027 BR20121100142 20100702 BR112012000142 A8 20201124 BR20121100142 20100702 BR112012000142 B1 20210518 BR20121100142 20100702 BR112012000143 A2 20161101 BR20121100143 20100623 BR112012000143 B1 20190806 BR20121100143 20100623 CA2767290 AA 20110113 CA20102767290 20100702 CA2767290 C 20170124 CA20102767290 20100702 CA2767304 AA 20110113 CA20102767304 20100623 CA2767304 C 20170110 CA20102767304 20100623 CL2012000040 A1 20120713 CL20120000040 20120106 CL52943 B 20160829 CL20120000040 20120106 CL2012000053 A1 20120713 CL20120000053 20120106 CN102472014 A 20120523 CN201080030879 20100623 CN102472013 A 20120523 CN201080030882 20100702 CN102472013 B 20180406 CN201080030882 20100702 CN105755884 A 20160713 CN201610122522 20100623 DE602010035440 D1 20160922 DE201060035440T 20100623 DE602010036272 D1 20161020 DE201060036272T 20100702 EP2452014 A1 20120516 EP20100796795 20100623 EP2452014 A4 20131120 EP20100796795 20100623 EP2452014 B1 20160810 EP20100796795 20100623 EP2452013 A1 20120516 EP20100796796 20100702 EP2452013 A4 20131120 EP20100796796 20100702 EP2452013 B1 20160907 EP20100796796 20100702 IN05254KN2011 A 20160826 IN2011KN05254 20111230 IN05257KN2011 A 20160826 IN2011KN05257 20111230 JP2012533000 T2 20121220 JP20120519087T 20100623 JP5719359 B2 20150520 JP20120519087T 20100623 JP2012532952 T2 20121220 JP20120519095T 20100702 KR101715428 B1 20170310 KR20127002536 20100702 KR20120093144 A 20120822 KR20127002536 20100702 KR20120098994 A 20120906 KR20127002537 20100623 PL2452014 T3 20170428 PL20100796795T 20100623 PL2452013 T3 20170228 PL20100796796T 20100702 RU2012103990 A 20130820 RU20120103990 20100702 RU2530022 C2 20141010 RU20120103990 20100702 RU2012104000 A 20130820 RU20120104000 20100623 RU2528394 C2 20140920 RU20120104000 20100623 SE200950534 A1 20101012 SE20090050534 20090707 SE533510 C2 20101012 SE20090050534 20090707 US2012160433 AA 20120628 US20100382573 20100702 US8778134 BB 20140715 US20100382573 20100702 US2012136146 AA 20120531 US20100382662 20100623 WO11004284 A1 20110113 WO2010IB52850 20100623 WO11004300 A1 20110113 WO2010IB53043 20100702 ZA201200327 A 20120926 ZA20120000327 20120116 ZA201200329 A 20120926 ZA20120000329 20120116 Link to current patent family on right

Polylactide stereocopolymer multifilament fibers were prepared by wet spinning and subsequent hot drawing. The stereocopolymers were poly-(L,D-lactide) [P(L,D)LA], L/D ratio 96/4, and poly-(L,DL-lactide) [P(L,DL)LA], L/DL ratio 70/30. They were dissolved in dichloromethane and coagulated in a spin bath containing ethanol. The hot-drawing temperature was 65°C. The draw ratios (DR) were upto 4.5 to the P(L,D)LA 96/4 filaments and upto 3 to the P(L,DL)LA 70/30 filaments. Wet spinning decreased crystallinities of both copolymers. Hot drawing increased the crystallinity of the P(L,D)LA 96/4 filament but not to the level of the original copolymer, whereas the as-spun and the hot-drawn P(L,DL)LA 70/30 filaments were amorphous. The filament diameter, tenacity, Young's modulus, and elongation at break were dependent on the DR. The maximum tenacity (285 MPa) and Young's modulus (2.0 GPa) were achieved with the P(L,D)LA 96/4 filament at the DR of 4.5. Respectively, the maximum tenacity of the hot-drawn P(L,DL)LA 70/30 filament was 175 MPa and Young's modulus 1.3 GPa at the DR of 3. Hot drawing slowed down in vitro degradation rate of both stereocopolymer filaments. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Poly(L,D-lactide) [P(L,D)LA], LL/D ratio 96/4, and poly(L,DL-lactide) [P(L,DL)LA], L/DL ratio 70/30, multifilament fibers were prepared by wet-spinning and the effects of the spin draw ratio and the coagulant on the morphological, thermal, and mechanical properties of the filaments were studied. The hydrolytic degradation of filaments was studied in vitro. The filament diameter and the mechanical properties of filaments were highly dependent on the spin draw ratio, whereas the coagulant had no or minor effect. The filament diameters were in the range of 11–36 μm and the maximum tenacity of 150 MPa was obtained at the spin draw ratio of 7.0 for both copolymers. The copolymer had the main importance on the crystallinity of filaments, but it was also affected by the duration of the coagulation process. The crystallinities of P(L,D)LA 96/4 filaments were in the range of 5–16%, whereas P(L,DL)LA 70/30 filaments were totally amorphous. The degree of crystallinity had effect on the hydrolytic degradation of filaments. The tenacity loss of P(L,D)LA 96/4 filaments was about 10% and that of P(L,DL)LA 70/30 filaments was as high as 50% after 24 weeks in vitro. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

In this study, the solubility and precipitation properties of medical-grade stereocopolymers were investigated. The solubility of the polymers was tested with eight different organic solvents and four nonsolvents. The solubility of poly(L,D-lactide) stereocopolymers was highly dependent on the L/D ratio of the copolymer. The phase-separation ability was tested by cloud-point titration with a solvent and a nonsolvent. The solvent was in all cases dichloromethane, and the nonsolvents were n-hexane, methanol, ethanol, and isopropyl alcohol. The results showed that n-hexane was the most efficient nonsolvent. Methanol and ethanol showed quite similar precipitation properties. Isopropyl alcohol was the least efficient nonsolvent of those studied. Also, the L/D ratio of the copolymer had an effect on the precipitation properties. The precipitation happened most easily when the L content was high. The molecular weight of the copolymer had only a slight effect on the phase separation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Novel cellulose fibres (Biocelsol) were spun by traditional wet spinning technique from the alkaline solution prepared by dissolving enzyme treated pulp directly into aqueous sodium zincate (ZnO/NaOH). The spinning dope contained 6 wt.% of cellulose, 7.8 wt.% of sodium hydroxide (NaOH) and 0.84 wt.% of zinc oxide (ZnO). The fibres were spun into 5% and 15% sulphuric acid (H2SO4) baths containing 10% sodium sulphate (Na2SO4). The highest fibre tenacity obtained was 1.8 cNdtex−1 with elongation of 15% and titre of 1.4 dtex. Average molecular weights and shape of molecular weight distribution curves of the celluloses from the novel wet spun cellulosic fibre and from the commercial viscose fibre were close to each other.

Wool is dyed for the first time with a mixture of two pure natural anthraquinone carboxylic acids, dermorubin and 5-chlorodermorubin (2:1), by means of the acid dyeing technique. The anthraquinone carboxylic acids are isolated from the fungus Dermocybe sanguinea and separated by multiplicative liquid-liquid partition using a stepwise pH gradient. The color of the dyed wool is investigated in terms of the CIELAB L*, a*, and b* parameters, and color-fastnesses to light, washing, and rubbing are tested according to ISO standards. The mixture of dermorubin and 5-chlorodermorubin dyes wool orange-red with good color-fastness properties. Our procedure is equivalent to the industrial winch- technique. The results indicate that wool has a high uptake for the anthraquinone carboxylic acids. Apparently, the ionic bonds between the carboxylate ions of the dye and the protonated amino groups of the wool enhance the color-fastness properties of the dyed fabric. Dermorubin and 5-chlorodermorubin have significant potential as textile dyes. affording useful alternatives to synthetic dyes.

3D nanofibrous chitosan-polyethylene oxide (PEO) scaffolds were fabricated by electrospinning at different processing parameters. The structural characteristics, such as pore size, overall porosity, pore interconnectivity, and scaffold percolative efficiency (SPE), were simulated by a robust image analysis. Mouse fibroblast cells (L929) were cultured in RPMI for 2 days in the presence of various samples of nanofibrous chitosan/PEO scaffolds. Cell attachments and corresponding mean viability were enhanced from 50% to 110% compared to that belonging to a control even at packed morphologies of scaffolds constituted from pores with nanoscale diameter. To elucidate the correlation between structural characteristics within the depth of the scaffolds’ profile and cell viability, a comparative analysis was proposed. This analysis revealed that larger fiber diameters and pore sizes can enhance cell viability. On the contrary, increasing the other structural elements such as overall porosity and interconnectivity due to a simultaneous reduction in fiber diameter and pore size through the electrospinning process can reduce the viability of cells. In addition, it was found that manipulation of the processing parameters in electrospinning can compensate for the effects of packed morphologies of nanofibrous scaffolds and can thus potentially improve the infiltration and viability of cells.

Wool and polyamide are dyed with the pure natural anthraquinones, emodin and dermocybin, using the mordant dyeing technique. The anthraquinones are isolated from the fungus Dennocybe sanguined. Potassiumaluminum sulphate, potassium dichromate, cobaltous sulphate, and ferrous sulphate are used as mordants. The color of each dyed material is investigated in terms of the Cielab L*, a*, and b* values, and color-fastnesses to light, washing, and rubbing are tested according to the ISO standards. Emodin dyes wool and polyamide yellow and red, whereas dermocybin confers purple and violet colors with color-fastness properties from good to moderate. Our procedure is facile and may be considered equivalent to the winch technique. The results show that wool and polyamide have a high uptake for the pure natural anthraquinones. These compounds have significant potential for new dyeing techniques, and they can provide useful alternatives to synthetic dyes.

Pure natural anthraquinones, emodin and dermocybin, isolated from the fungus Dermocybe sanguinea, are for the first time used as disperse dyes for polyester and polyamide fabrics using a high-temperature dyeing method, accompanied with a reference dyeing with CI Disperse Red 60. The color of each dyed material is investigated in terms of the CIELAB L*, a*, and b* values, and color fastness to light, washing, and rubbing are tested according to the ISO standards. Emodin dyes polyester bright yellow and dermocybin bright reddish-orange, and the fabrics show excellent color-fastness results. Emodin and dermocybin successfully dye polyamide brownish-orange and wine-red, respectively, but the fastness results are only moderate. This study shows that pure natural anthraquinone compounds can produce bright hues and color-fastness properties equivalent to those of synthetic disperse dyes, and thus providing useful alternatives to the synthetics.

In this work the possibility and potential of treating cotton fibers and yarns instead of fabrics with monocomponent cellulases was investigated. Different pretreatments on fibers were performed and tested in order to improve the accessibility of cotton to enzymatic modification. The enzymatic treatments were evaluated microscopically and by analysing the effects of treated fibers on spinnability, yarn evenness, tenacity and pilling. The accessibility of the cotton fibers for cellulases could be increased by different pretreatments. Steaming of fibers prior to enzymatic treatment was found to be an efficient way to increase hydrolysis levels. Cellulase treatments of carded yarns resulted in modification of yarn properties. Decrease in yarn hairiness was observed and the knitted fabric made of the treated yarn showed a lowered tendency towards pilling. In all cases endoglucanase activity rather than cellobiohydrolase activity was responsible for these modifications.

Two different types of cotton fabrics, i. e. cotton twill and cotton poplin, were treated with purified Trichoderma reesei cellulases. Methods used to evaluate the enzyme effects included weight loss, tear strength, bending hysteresis, wrinkle recovery and pilling tendencies. When the different fabric properties at the same weight loss level were compared, it was apparent that cellobiohydrolase I (CBH I) and endoglucanases had different effects on cotton fabrics. Endoglucanases caused more strength loss than CBH I but had also positive effects on the bending behaviour and pilling properties. The two endoglucanases tested differed in their action. At low hydrolysis levels practically no strength loss was obtained with these endoglucanases whereas at higher dosages EG II caused significantly higher strength losses as compared to EG I. A positive result in the pilling was, however, also obtained with these low enzyme levels, indicating practically no strength loss.

Reconstituted cellulose spontaneously self-assembles at surfaces from an alkaline cellulose solution (ca. 1wt%, pH14, prepared with an enzymatic method from wood pulp) into porous films with approximately 300nm thickness per layer, for example onto immersed tin-doped indium oxide (ITO) electrodes. Sequential multi-layer deposition allows control over the thickness of the assembled films. The hydrophilic properties of the cellulose film electrodes are utilised here (i) as dip-probe with capillary force picking up sample solution and (ii) as flow-through generator-collector probe, for example for future application in in situ chromatographic separation in end-column detection with nano-molar sensitivity.

Hardwood dissolving pulp was treated with purified Trichoderma reesei endoglucanases and cellobiohydrolases. Endoglucanases were more efficient in hydrolysing pulp carbohydrates than were the cellobiohydrolases at the same protein dosage. Endoglucanases also lowered the viscosity and improved the alkaline solubility more dramatically. There was a clear correlation between the alkaline solubility and viscosity, and therefore the solubility could only be improved by lowering the viscosity of the pulp. At the same degree of cellulose degradation, endoglucanase II was found to be most effective in reducing the viscosity and thus improving the solubility. Cellobiohydrolases had a less pronounced effect on the viscosity or solubility.

A systematic investigation of structurally identical flame retardant viscose, modal and polyester blended fabrics and fibres was carried out in order to develop a chemical basis for more effective products based on organic and inorganic flame retardants. The oxygen indices and chemical compositions of phosphorus-nitrogen flame retardants (P-N) were used in efficiency and synergy evaluations. A new flame retardant viscose fibre containing silicid acid was included in the comparative evaluation procedure. Thermal gravimetry and X-ray diffractometry were used for determine physical factors during pyrolyzing of fibres. Charred residues were analyzed by applying elementary and solid 13-C NMR (CPMAS) spectrometry. The pyrolysis gas-liquid chromatographer connected with a gas phase FT infrared spectrometer was applied to identify the decomposition products of P-N-containing fabrics.

Protein-loaded multifilament fibers were fabricated by the wet-spinning method. The polymers which were tested included poly(L,D-lactide) [P(L,D)LA], L/D ratio 96/4 and poly(L,DL-lactide) [P(L,DL)LA], L/DL ratio 70/30. The polymers were dissolved in dichloromethane and bovine serum albumin (BSA) was dissolved in water, respectively. The solutions were mixed together using a probe sonicator to form a polymer-protein emulsion. This emulsion was extruded to an ethanol spin bath. The fibers possessed a distinct sheath-core structure, where the inner core was porous and the outer sheath was smooth. The diameters of the filaments were in the range of 46 and 70 μm. The tenacity values of the filaments were between 7 and 17 MPa. In vitro drug release rate of the P(L,DL)LA 70/30 filament was faster than that of the P(L,D)LA 96/4 filament. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The present invention relates to a method for dissolving cellulose. The method comprises - introducing cellulosic raw material, - treating the cellulosic raw material in an enzymatic treatment process, - mixing the cellulosic raw material after the enzymatic treatment in an aqueous solution in order to obtain an aqueous intermediate product containing the cellulosic raw material of at least 3.5 wt.-%, alkali metal hydroxide between 3.5 wt.-% and 7 wt.-% and zinc salt, - freezing the intermediate product to a solid state, and - melting the frozen intermediate product. The present invention also relates to a cellulosic product obtained from a solution comprising dissolved cellulose.Patent family as of 7.9.2021 CA2723573 AA 20101104 CA20092723573 20090506 CA2723573 C 20161115 CA20092723573 20090506 CN102037019 A 20110427 CN200980116326 20090506 CN102037019B 20140402 CN200980116326 20090506 DE602008047850D1 20170126 DE200860047850T 20080506 EP2116557 A1 20091111 EP20080397510 20080506 EP2116557 B1 20161214 EP20080397510 20080506 IN301706 B 20181005 IN2010DN07547 20101026 RU2010150201 A 20120827 RU20100150201 20090506 RU2500687 C2 20131210 RU20100150201 20090506 US2011112286 AA 20110512 US20090991299 20090506 US8492125 BB 20130723 US20090991299 20090506 WO09135875 A1 20091112 WO2009EP55479 20090506 Link to current patent family on right

The objectives of the Biocelsol project were to understand the enzymatic action on the cellulose and its impact on the structure and processability of cellulose, to develop viable processes for fibres, films, casing coatings, beads and sponges as well as to demonstrate them. The effect of combined chemical, mechanical and enzymatic treatments to produce dissolving cellulose with high alkaline solubility and acceptable viscosity was studied. The pulp characteristics such as alkaline solubility, viscosity, DP, crystallinity, porosity, fibre characteristic and WRV were analysed. Knowledge of the factors affecting cellulose properties and enzymatic treatments was obtained. As a result of different pre-treatments and enzymatic treatment with experimental or commercial enzymes, cellulose with high solubility and good solution properties was prepared and scaled up with low yield loss in the enzymatic treatment. Procedure to prepare cellulose with high solubility and good solution properties in aqueous alkali was developed with low yield loss in the enzymatic treatment. The procedure includes pretreatment of dissolving type pulp and enzymatic treatment with commercial or experimental enzymes. The treated cellulose is dissolved to obtain solution containing 4-6.5% cellulose, 0-1.3% zinc oxide and 7.8% sodium hydroxide depending on the application. Processes for fibres, films, impregnated webs, fibrous casings, beads and sponges were developed utilising the enzymetreated pulp without any need of carbon disulphide or other organic solvent. The highest tenacity of fibres obtained at laboratory scale remained close to 2 cN/dtex, which was close to the reference viscose fibres typical for nonwoven applications. The fibres produced for application trials for yarns, woven fabrics and for hydroentangled nonwovens were running without major problems. The industrial scale dissolution trial to produce fibrous casings by coating and bonding of the special paper web with Biocelsol was running well, even though the solution parameters were not yet optimal. Beads were successfully prepared from Biocelsol solution and their characteristics turned out to be different and probably better than of the beads made from the viscose solution. In the coming future bio-based binders for nonwovens are developed utilizing the excellent film forming behavior of particles produced via the controlled precipitation of alkaline soluble cellulose. The research and development gaps of the Biocelsol project were identified to be the scaling up of the best pretreatment method, the high alkali to cellulose ratio of the solution, the low fibre tenacity and the lack of the pilot scale production of fibres for application trials. All these are considered and are the topics of the presently running projects. NMP-CT-2003-505567 Specific Targeted Research Project (STREP) Nanotechnology and nanosciences, knowledge based multifunctional materials, new production processes and devices (NMP) Biotechnological Process for Manufacturing Cellulosic Products with Added Value (BIOCELSOL).

Cellulose is an ideal raw material for a large variety of products, because it is biodegradable, renewable, non-toxic and plentiful. The most important cellulose source is wood, which contains about 40% of cellulose from its dry weight. In order to utilise cellulose for high value applications it is separated from the other wood components in the chemical pulping process. The purified cellulose is known as dissolving grade chemical pulp and its cellulose content is from 94% to 97%. The pulp is most commonly used for regenerated cellulosic products such as cellulosic fibres, films, casings and sponges. The production of regenerated items requires the dissolution of cellulose and subsequent regeneration into the desired shape. The dissolution of cellulose is challenging because of strong fibrillar structure of cellulose, which restricts its direct dissolution into cheap and common solvents. Consequently, most of the regenerated cellulosic products are manufactured by the well-known viscose process in which a highly toxic carbon disulphide (CS2) is needed to transform cellulose into a soluble form. However, the enzyme-assisted method offers an ecological way to dissolve and process cellulose, and accordingly to eliminate the environmental load caused by the viscose process. Dissolving grade total chlorine free (TFC) sulphite pulp, a common raw material for the viscose process, was treated with commercial enzyme preparation. The enzymatic treatment decreased the SCAN viscosity of the pulp by 33% and solubilised around 3% of the pulp material. The enzyme-treated pulp was dissolved in aqueous sodium zincate solution and regenerated to cellulosic fibres (Biocelsol) using a wet spinning technique. The spinning dope contained 6wt% of cellulose, 7.8wt% of sodium hydroxide (NaOH) and 0.84wt% of zinc oxide (ZnO). The fibres were spun into 15% sulphuric acid (H2SO4) bath containing 10% of sodium salt (Na2SO4), stretched in a hot water bath, washed, finished and dried. The characteristics of the novel cellulosic Biocelsol fibres were measured and compared with the commercial viscose fibres. The highest tenacity of the obtained fibres was 1.8 cNdtex-1 with elongation of 14% and titre of 1.8 dtex. The crystallinity degree of these fibres was 47% and average size of crystallites 40Å. The tenacity and elongation of the Biocelsol fibres were slightly lower, but the crystallinity degree significantly higher than the comparable values of the commercial viscose fibres (2.1 cNdtex-1, 17% and 28%, respectively). The shape of the Biocelsol fibre cross section was circular and the structure of surface furrowed, whereas the typical cross section of the viscose fibres is serrated and the surface structure striped. The specific flexural rigidity of the Biocelsol fibres was 0.26 mNmm2tex-2 and of the viscose fibres 0.13 mNmm2tex-2. The higher rigidity of the Biocelsol fibres is mainly due to their circular cross section. The internal surface of the fibres as a function of porosity was measured by SAXS. The internal surface of the Biocelsol fibres was more than twofold as compared to the viscose fibres (1008 m2cm-3 and 428 m2cm-3, respectively). This is explained by the fast coagulation rate of the Biocelsol fibres, which favours the development of pores. Consequently, the water swelling of the Biocelsol fibres was 1.5 times higher than that of the viscose fibres, which is an interesting property regarding the hygiene applications, for example. The raw material and fibre forming process of the Biocelsol and the viscose fibres are close to each other. The most significant difference is the absence of carbon disulphide in the Biocelsol process. Even though, the chemical composition of the fibres is alike, the properties differ largely from each other. This is probably due to the rapid solidification of the Biocelsol spinning solution in the acidic bath without any chemical reaction. This leads to the specific properties of the fibres and might restrict the development of higher tenacity fibres at the moment. The advantage of the enzyme-aided pulp treatment method is the total elimination of CS2; it is not needed, because the cellulose dissolves directly after the enzymatic treatment. The enzymes originate from nature, are biodegradable and do not threaten the environment. Their mode of action is catalytic, thus the dosages needed are low and the optimal processing conditions moderate. The regenerated cellulose products manufactured from enzyme-treated pulp are naturally biodegradable. In addition, they do not require bleaching, because no colouring and smell-forming sulphur by-products are formed in the process. Due to the absence of carbon disulphide, the cellulose solution could also be used for application, which does not allow any sulphur traces. The research was carried out in the EU FP6 project Biocelsol - Biotechnological Process for Manufacturing Cellulosic Products with Added Value, with contract number of NMP2-CT-2003-505567. The text reflects only the authors’ views and the Community is not liable for any use that may be made of the information contained therein.

The incorporation of polysilicic acid into the structure of a cellulosic fibre enhances the fire resistance of the hybrid by two distinct mechanisms. One is the formation on the fibre surface of an inherently incombustible char, and the other is a lowering of thetemperature at which water is released from the fibre. This paper examines the mechanismsin question.

Never-dried pine sulphate paper grade pulp was treated with specific enzyme mixture from Trichoderma reesei , which increased the alkaline solubility of pulp from 20% to 69% and decreased the DP W from 1124 to 622. The effect of different viscose process additives and zinc oxide on solubility was studied. The best combination for producing a good spinning dope was chosen. The fibres were spun using a wet spinning machine and titre, tenacity and elongation of the fibres were determined. The strongest fibres obtained have tenacity of 1.2 cN/dtex and elongation of 12-13%, which are comparable to the properties of cotton.

Blends of microcrystalline chitosan (MCCh) with cellulose xhanthate alkaline solutions were prepared to investigate the effects of aqueous MCCh gel concentration and additives on the spinnability of hybrid cellulose/chitosan fibers and their properties. The properties of the spinning solution were mainly dependent on the concentration of MCCh in the aqueous gel-like dispersion and the amount mixed into the cellulose xhanthate solution. Sodium alginate chemically close to cellulose and chitosan was used as an additive to improve the miscibility of chitosan due to the ionic bonds formed with chitosan 2-amino groups. Using an optimized ratio of 2 : 1 of MCCh to the sodium alginate, a maximum of 6% of MCCh calculated from alpha-cellulose content could be introduced into the sodium xhanthate solution containing originally 9% of alpha-cellulose. The yield of MCCh in the resulting fibers was dependent on the molecular mass, and varied between 73–82%. The strength, elongation, and color of the resulting hybrid fibers were only slightly changed and the WRV remarkably increased compared to standard fibers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1725–1730, 2000

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The well-known ability of various cellulase enzymes to degrade cellulose has already been applied in order to improve the conventional cellulose xanthate process. The aim of the present CELSOL-research is to develop a method for making cellulose directly soluble in aqueous sodium hydroxide, without chemical substitution of the cellulose. The method is based on a combination of mechanical and biochemical treatments though efficient dissolution of hardwood pulps requires an additional chemical pretreatment. The effect of combined treatments on the supermolecular structure of common pulps was measured by the change in the degree of polymerisation and by the solubility of the cellulose in 9wt% aqueous sodium hydroxide. The celluloses treated by above methods are characterized to be highly soluble and the alkaline solution, containing 3-7 w/w% cellulose, can be regenerated to films and fibres.

Dissolving pulp can be modified to a more alkaline soluble form by cellulases. The alkaline solubility was found to clearly correlate with the decrease in viscosity. Endoglucanases, especially EG II, decreased the viscosity most efficiently when compared at the same cellulose degradation level. The effect of EG II could not be improved by the action of hemicellulases. According to preliminary fibre spinning trials from enzyme-treated hardwood pulp it has been shown that it is possible to spin fibres from enzyme-treated cellulose using an advanced wet spinning line.

Conducting polyester PET and polyamide PA-6 fibre and fabrics were prepared by in-situ chemical oxidative polymerisation using super critical fluid assisted process. The fibre materials and cloths produced were characterized by means of FTIR, WAXD, SEM, and DSC and two-probe resistivity. The samples were studied also by means of washing them several times. Homogeneous treated fibre materials with sustainable properties were produced. Melt spun fibre material of inherently conducting polymer blends have been reported earlier. Reasonable mechanical and electrical properties (resistance of 105…107 Ω/cm) are typical for blend of polypropylene and polyaniline. With bi-component extrusion technology the fibre as good as 103…105 Ω/cm is reachable.

Dissolved cellulose was contacted with dissolved linear or slightly branched lignophenol polymers in alkaline solution, and films were formed through precipitation. Lignophenol is a polymeric lignin derivative isolated from wood meal, and due to its size and chemical structure, it is expected to a better model for natural lignin compared to the previously exploited small lignin model molecules. Smooth and even of cellulose-lignophenol films were achieved, and the interactions between cellulose and lignophenol were tentatively detected. The formed film structures had the crystalline form of cellulose II, and they did not contain any fibril-like material. Although the amount of hemicelluloses was negligible, it seems that the lignin modelling lignophenol tended to positively interact with cellulose.

The aim of this work was to study the solubility of chemical pulps and the effects of ZnO and NaOH concentrations on the solution properties. The pulps were mechanically shredded, pretreated using cellulase, and dissolved directly into aqueous sodium zincate. The solubility of pulp was observed visually by a microscope, and the viscosities of solutions were measured by a rotational rheometer and a ball-drop method.