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1.
Facile embedding of TiO2 nanoparticles onto cotton fabric has been successfully attained by ultraviolet light irradiations. The adhesion of nanoparticles with fibre surface, tensile behaviour and physicochemical changes before and after ultraviolet treatment were investigated by scanning electron microscopy, energy dispersive X-ray and inductive couple plasma-atomic emission spectroscopy. Experimental variables i.e. dosage of TiO2 nanoparticles, temperature of the system and time of ultraviolet irradiations were optimised by central composite design and response surface methodology. Moreover, two different mathematical models were developed for incorporated TiO2 onto cotton and tensile strength of cotton after ultraviolet treatment and used further to testify the obtained results. Self-clean fabric through a synergistic combination of cotton with highly photo active TiO2 nanoparticles was produced. Stability against ultraviolet irradiations and self-cleaning properties of the produced fabric were evaluated.  相似文献   

2.
The surface morphology of the CO2 laser treated grey cotton fabrics was studied which showed a characteristics sponge-like structure on cotton fibres after treating with CO2 laser irradiation. The laser treatment parameters ranging from 100 to 150 pixel time and 40 to 70 dot per inch (dpi) were irradiated on the grey cotton fabrics directly and the degree of physical modifications, such as surface morphology, wettability and fabric strength, were changed accordingly with various laser treatment parameters. The surface morphology, wettability and tensile strength of cotton fibre treating with laser were evaluated using different instruments, such as Scanning Electron Microscope (SEM), contact angle meter and tensile strength machine. In spite of creating a sponge-like structure on fibre surface after treating with laser, the wettability of the samples was highly improved but the tensile strength was decreased.  相似文献   

3.
Coconut fibres were subjected to chemical treatment to obtain softer and finer fibres, suitable to blend with other finer fibre like jute. The chemical softening recipe was optimized using Box-Behnken design of experiments as 40 % Na2S, 10 % NaOH and 6 % Na2CO3, which notably reduced the fineness (33 %) and flexural rigidity (74 %) and improved tensile property of coconut fibre. Effect of softening of coconut fibre on its process performance was studied in high speed mechanized spinning system at different blend ratios with jute. Blending with jute assists in spinning of coconut fibre to produce yarn of 520 tex at production rate of 5-6 kg/h, as compared to 15 kg/day for hand spun 5300 tex raw coconut fibre yarn in manual system. Analysis of blended yarn structure in terms of packing density, radial distribution of fiber components (SEM) and mass irregularity were investigated. SEM shows yarns made from softened coconut fibre -jute blends are more compact than raw coconut fibre -jute blend yarns. Coconut fibres were preferentially migrated to core of the yarn. Major yarn properties viz., tensile strength, and flexural rigidity of raw and chemically softened blended yarns were compared against their finest possible 100 % coconut fibre yarn properties. Yarn made up to 50:50 chemically softened coconut fibre-jute blend showed much better spinning performance, and having superior property in terms of reduced diameter, higher compactness, strength, initial modulus and less flexural rigidity than 100 % raw, 100 % chemically softened coconut fibre rope, and raw coconut fibre-jute blend yarns.  相似文献   

4.
The main objective of this project was to investigate two low cost treatment methods, namely bag retting and treatment with white rot fungi, which could be applied to hemp fibre with low environmental impact to improve its interfacial bonding with polypropylene. Wet chemical analysis, FTIR, scanning electron microscopy (SEM), X-ray diffraction (XRD), zeta potential and single fibre tensile testing were used to characterise the effect of treatment on hemp fibres. It was found that all the treatments increased the tensile strength of composites. White rot fungi Schizophyllum commune (S.com) treated fibre composites had the highest tensile strength of 45 MPa, an increase of 28% compared to composites using untreated fibre.  相似文献   

5.
There is great interest in the plant Cannabis sativa (hemp) as a source of technical fibres for the reinforcement of polymers in composite materials due to its high mechanical properties. In this work, the effect of enzymatic, hydrothermal and alkaline treatments on the composition and mechanical properties of hemp fibre are compared. The influence of enzyme concentration and treatment time was examined (2.5–80 % Pectinex® Ultra SP-L, 6–48 hrs). Additionally, hydrothermal (170 °C, 10 bars) and alkaline treatments (18 wt. % NaOH, 40 °C) were used as pre-treatments to observe their effect on subsequent enzymatic treatment. The composition of hemp fibre was analysed by wet chemistry and Fourier transform infrared spectroscopy, while microstructure and mechanical properties were examined by scanning electron microscopy and tensile testing, respectively. Enzymatic treatment resulted in extensive fibrillation and removal of non-cellulosic components, especially when combined with hydrothermal treatment. However, a lengthy enzymatic treatment or combinative enzymatic-alkaline treatment led to extensive fibre breakdown that was accompanied by a pronounced reduction in the mechanical properties. Enzymatic treatment decreased Young’s modulus and tensile strength by 77 and 73 % respectively, and alkaline treatment by 83 and 36 %. The hydrothermal treatment resulted in only minor changes in these properties.  相似文献   

6.
Applying nitrogen (N) fertilizer to grass generally increases N concentration in herbage. Not as well documented, however, are N fertilizer effects on concentrations of N in plant cell walls and lignocellulose. The objective four study was to ascertain how N fertilizer applied with or without a nitrification inhibitor would affect N concentrations in the cell wall (neutral-detergent fibre (NDF)) and lignocellulose (acid-detergent fibre (ADF)) of smooth bromegrass (Bromus inermis Leyss). Nitrogen fertilizer ((NH4)2SO4) was applied at 0, 125, or 230 kg N ha?1 in combination with 0, 2–5, or 50 kg ha?1 of nitrapyrin (2- chloro-6-(trichloromethyl) pyridine) to smooth bromegrass in April of 1985 and 1986. Herbage was harvested at 2, 4, 6 and 8 weeks after treatment. Freeze-dried herbage samples were analysed for in vitro digestible dry matter (IVDDM), total N, and N in neutral- and acid-detergent fibre (NDFN and ADFN, expressed as g kg?1 NDF and ADF, respectively). Nitrapyrin had no effect on IVDDM, total N, NDFN or ADFN, Nitrogen fertilizer increased concentrations of total N in herbage dry matter, and increased N concentrations in NDF and ADF. Most of the increase in total N concentration occurred in the neutral-detergent soluble portion. When NDFN and ADFN concentrations were expressed on a total N basis (g k g?1 of total N), N fertilizer had no effect. Available fibre N (AFN; calculated as NDFN minus ADFN, each expressed as g kg?1 total N) was not affected by N fertilizer. The average AFN concentration was 93 g kg?1 total N. Nitrogen fertilizer did not affect herbage quality; however, age of herbage had marked effects on herbage quality.  相似文献   

7.
The microbial transglutaminase (mTGase) is used as a bio-catalyst to repair the wool damages caused by chemical or enzymatic treatments. In this paper, the effect of mTGase on the degree of yarn strength, area shrinkage, wettability, and the dyeing properties of wool was investigated. Through mTGase treatment, the yarn strength was improved about 22.2 %. The knitted wool fabrics treated with mTGase after pretreatment of H2O2 and protease displayed 7.5 % of area shrinkage and about 22.3 % recovery in tensile strength when compared with those treated without mTGase. Also, mTGase treatment could improve the wettability and dyeing properties of wool fabrics. With the increase of mTGase concentration, the initial dye exhaustion increased significantly and the time to reach the dyeing equilibrium was shortened. It was evident that the improvement of dyeing properties was closely related to the improvement of wettability performance of wool fabric by using transglutaminase.  相似文献   

8.
The application of poly (p-phenylene-2, 6-benzobisoxazole) (PBO) fiber as reinforcement in composite material was restricted by its photo-degradation, therefore, some measures should be considered to protect PBO fiber against UV aging. In this study, A series of multilayer coating for (POSS/TiO2)n was prepared on PBO fiber surface via LbL assembly technique for enhancement of UV resistance. TiO2 as UV absorbing material was used to relieve UV-degradation of PBO. Surface elemental composition, surface morphology, mechanical and interfacial properties, and UV resistance of uncoated and coated PBO fibers were investigated. These experimental results show multilayer coating of (POSS/TiO2)n was uniform deposition on fiber surface after treatment, tensile strength decreased to certain extent, interfacial shear strength increased in a small range and UV resistance is obvious enhanced. After the same accelerated aging time under UV irradiation, the retention of tensile strength and intrinsic viscosity of coated PBO fibers were much better than that of untreated PBO fibers.  相似文献   

9.
From early times, jute fibre has been generally conditioned for easy spinning by adding oil and water in the form of an emulsion. The commonly used oil consists of C12–C31 fractions of mineral oil that sometimes impart different intensities of oily (kerosene) or fishy smell to the end product. In the present work, efforts have been made to find a suitable sustainable substitute of mineral oil based conditioning agent for spinning of jute yarn and for this, three types of vegetable oil (rice bran oil, palmolein oil and castor oil), a silicone emulsion, a mixed enzyme system and glycerine have been used separately or in combinations as conditioning agents for jute fibre before its mechanical processing for making yarn in jute spinning machines. Considering comparable mechanical process performance for spinning of jute fibre (viz., fibre loss as droppings during processing, moisture retention prior to spinning stage and spinning end breakage rate), tensile properties of yarn, and lower yarn hairiness, it may be suggested to use 2.5% castor oil alone, or 2% castor oil in combination with 0.1–0.5% glycerine in the form of oil-in-water emulsion as the most suitable alternatives to conventional mineral oil-based jute conditioning agent to spin ordinary jute yarn.  相似文献   

10.
Transfer printing with disperse dyes on cotton fabric modified with an aqueous tolylene diisocyanate derivative (TDD) was discussed in this paper. The effect of the degree of substitution (DS) on color strength (K/S value) of the modified and transfer printed fabric was investigated. The DS of the cotton fabric increased with increases in TDD concentration and curing temperature and time, while the sample whiteness decreased with the increasing curing temperature and time. And the change of structure of the modified cotton fabric was characterized by FT-IR spectra, DSC curves, and SEM images. All of the factors, such as the concentration and molecular weight of poly(ethylene glycol), the DS of the modified fabric, the transfer printing temperature and time would affect the K/S value of the sample. After transfer printing with disperse dye, the K/S value and printing fastness of TDD-modified cotton fabric were higher than those of cotton control fabric, the change of chromatic difference was not obvious, but the tensile strength of the modified fabric was lower than that of original cotton.  相似文献   

11.
The chemical structure of a new gemini dicationic imidazolium ionic liquid, 3,3′-[1,2-ethanediylbis (oxy-2,1-ethanediyl)]-bis[1-methyl-imidazolium]-dibromide (PEG150-DIL) was established by 1H-NMR and elemental analyses. Then, PEG150-DIL was applied to pretreat ramie fiber. PEG150-DIL treated ramie fiber was characterized by FT-IR, XRD, DSC-TG and FE-SEM. Finally, the mechanical and dyeing properties of PEG150-DIL pretreated ramie fibers were studied. The optimum condition of PEG150-DIL modification was carried out at 100 °C for 30 min. The color strength increased obviously with the duration time and temperature of the PEG150-DIL. The tensile strength and strength retention of PEG150-DIL -treated ramie fibers decreased with the increase of pretreating time and temperature. The tensile strength retention was 86.20 % under optimal PEG150-DIL pretreating condition (100 °C, 30 min).  相似文献   

12.
Aligned epoxy-matrix composites were made from hemp fibres defibrated with the fungi Phlebia radiata Cel 26 and Ceriporiopsis subvermispora previously used for biopulping of wood. The fibres produced by cultivation of P. radiata Cel 26 were more cellulose rich (78%, w/w) than water-retted hemp due to more degradation of pectin and lignin. The defibrated hemp fibres had higher fibre stiffness (88–94 GPa) than the hemp yarn (60 GPa), which the fibre twisting in hemp yarn might explain. Even though mild processing was applied, the obtained fibre strength (643 MPa) was similar to the strength of traditionally produced hemp yarn (677 MPa). The fibre strength and stiffness properties are derived from composite data using the rule of mixtures model. The fibre tensile strength increased linearly with cellulose content to 850 MPa for pure cellulose. The fibre stiffness increased also versus the cellulose content and cellulose crystallinity and reached a value of 125 GPa for pure crystalline cellulose.  相似文献   

13.
Sansevieria (genus) cylindrica (species) belongs to Agavaceae family plant fiber first time used as a reinforcing agent in the epoxy system. Fibre extracted from leaves, fairly lesser density, porosity, higher strength to weight ratio (hereafter called SCF) and these fibers were alkali-treated and yet impregnated on the epoxy system using wet hand lay up technique in order to compare with untreated fiber on performance. DMA, TGA, DSC, FTIR, SEM, degradation temperature, flexural and tensile tests were performed for untreated and alkali-treated epoxy composites using different SCF volumes viz. 1 vol.%, 5 vol.%, 7 vol.% and 9 vol.%. Alkali treated fibre were found to have higher initial and final degradation temperatures and flexural and tensile strength. The removal of the amorphous hemi-cellulose on alkali treatment was played an instrumental in improving properties. A 3 °C increase in glass transition temperature and decomposition temperature were recorded respectively and over all treated SCF composites reinforced on the epoxy were shown significant results than untreated. Storage modulus and tan ?? were observed well at 9 vol.% treated SCF while flexural and tensile were increased by 35 and 13 % for SCF treated composites respectively.  相似文献   

14.
In this study, polyester and polypropylene staple fibers were selected as the raw material, and then processed through roller-carder, cross-lapper and needle-punching machine to produce needle-punched non-woven fabrics. First, the experiment was planned using the Taguchi method to select processing parameters that affect the quality of the needle-punched non-woven fabric to act as the control factors for this experiment. The quality characteristics were the longitudinal and transverse tensile strength of the non-woven fabric as well as longitudinal and transverse tear strength. The L18 (21×37) orthogonal array was selected for the experiment as it offered an improvement on the traditional method that wastes a lot of time, effort and cost. By using the analysis of variance (ANOVA) technique at the same time, the effect of significant factors on the production process of needle-punched non-woven fabrics could be determined. Finally, the processing parameters were set as the input parameters of a back-propagation neural network (BPNN). The BPNN consists of an input layer, a hidden layer and an output layer where the longitudinal/transverse tensile and tear strength of the non-woven fabric were set as the output parameters. This was used to construct a quality prediction system for needle-punched non-woven fabrics. The experimental results indicated that the prediction system implemented in this study provided accurate predictions.  相似文献   

15.
The inherent properties of rayon fibre have been changed with additional properties through graft copolymerization of acrylamide, AAm, by chemical method using ceric ammonium nitrate/nitric acid, (CAN/HNO3), as a redox initiator and γ-radiation induced mutual method. Reaction conditions such as monomer and initiator concentration, liquor ratio, temperature and time of reaction, amount of radiation dose have been optimized with respect to percentage of grafting. Maximum percentage of grafting (Pg), (40 %) using CAN/HNO3 was obtained at [CAN]=31.92×10?3 moles/l, [HNO3]=79.36×10?2 moles/l, [AAm]=14.07×102 moles/l in 20 ml of H2O at 45 °C within 120 min while in case of radiation induced method, maximum Pg (30 %) was obtained at higher monomer concentration (28.14×10?2 moles/l) and time (180 min) in 10 ml of H2O at room temperature with total dose exposure of 11.178 kGy. The graft copolymers were characterized by FTIR, thermogravimetric and scanning electron micrographic analysis. Swelling behaviour in water, methanol, ethanol, acetone and DMF and dyeing and flame retarding properties of rayon fibre and grafted rayon fibre were investigated. Percent dye uptake (71.8 %) was found to be higher than that observed for the pristine fibre (57.4 %) and the grafted fibre after post phosphorylation reaction showed excellent flame retarding properties.  相似文献   

16.
Process parameters such as gelation and curing temperatures are parameters that influence the pultruded kenaf reinforced vinyl ester composites profile quality and performance. The effect of gelation and curing temperatures on mechanical (tensile, flexural and compression properties) and morphological properties of pultruded kenaf reinforced vinyl ester composites were analyzed. Obtained results indicated that increase of gelation and curing temperatures during the pultrusion process of kenaf reinforced vinyl ester composites influenced the mechanical properties of the composites. When the gelation and curing temperatures were increased, tensile strength, tensile modulus, flexural strength, flexural modulus and compressive strength were affected and they were either increased or decreased. The factors that influenced these results include improper curing, excessive curing, water diffusion, and the problems associated with interfacial bonding between fibre and matrices. The optimum values of the tensile strength for gelation and curing temperatures of kenaf pultruded composites were at 100 °C and 140 °C, tensile modulus at 80 °C and 180 °C, flexural strength at 100 ° and 140 °, flexural modulus at 120 ° and 180 °, and compressive strength at 120 °C and 180 °C, respectively. The scanning electron micrographs of tensile fractured samples clearly show that with the increase in gelation temperature, it creates the lumens between matrix and kenaf fibre thus reducing tensile properties whereas increasing the curing temperature caused less fibre pull out and enhanced fibre/matrix interfacial bonding.  相似文献   

17.
The wrinkle-resistant property of cotton specimens treated by 1,2,3,4-butanetetracarboxylic acid (BTCA) and catalysed by sodium hypophosphite (SHP) in the presence of TiO2 or nano-TiO2 has been evaluated in the present study. In this study, Scanning Electron Microscopy proved the presence of TiO2 or nano-TiO2 on the fibre surface. It was also found that 0.1–0.2 % TiO2 or nano-TiO2 was the optimum concentration to enhance the wrinkle-resistance of BTCA-SHP-treated cotton fabrics. In addition, the TiO2 or nano-TiO2 added in the wrinkle-resistant treatment could act as a multi-functional finishing agent to improve the UV protection property while they are safe to human skin as proved by the cytotoxicity test. Therefore, TiO2 or nano-TiO2 was evident that they could enhance the finishing performance and minimise the side effect.  相似文献   

18.
Depithed Sudanese bagasse was examined for its suitability for pulp production. Bagasse fibre dimensions, morphological and chemical characteristics are reported. The pulping trials were carried out with soda–AQ and alkaline sulphite–AQ (AS–AQ) methods and soda method as reference. The AS–AQ pulping gave the best results in yield, degree of delignification, mechanical and optical pulp properties. Blending of bagasse and bamboo alkaline sulphite–anthraquinone pulps in different ratios gave well-balanced pulp strength characteristics with good tensile and tear indices, widening the range of different end products from bagasse pulp. Totally chlorine free bleaching (Q1O/PQ2P) of the best unbleached bagasse pulps gave bleached pulps of 76.9% ISO brightness, suitable for use in writing and printing grades of paper.  相似文献   

19.
In this research, results of an experimental interaction effect of operating parameters on tensile strength carbon fibers from a commercial PAN-based precursor are investigated. Ten parameters at two and four levels (L32=21×49) were investigated: stabilization temperature at first stage (STFIS), stabilization duration time at first stage (SDTFIS), stabilization temperature at second stage (STSS), stabilization duration time at second stage (SDTSS), stabilization temperature at third stage (STTS), stabilization duration time at third stage (SDTTS), stabilization temperature at fourth stage (STFOS), stabilization duration time at fourth stage (SDTFOS), carbonization temperature (CT), and carbonization duration time (CDT). In this study, Taguchi method was used initially to plan a minimum number of experiments. Statistical analysis, analysis of variance (ANOVA), was also employed to determine the relationship between experimental conditions and yield levels. ANOVA was applied to calculate sum of square, variance, ratio of factor variance to error variance and contribution percentage of each factor on response. The results show that increasing all of parameters improves tensile strength performance. The optimum levels of influential factors, determined for tensile strength are STFIS 200 °C, SDTFIS 120 min, STSS 225 °C, SDTSS 120 min, STTS 240 °C, SDTTS 120 min, STFOS 260 °C, SDTFOS 60 min, CT 1400 °C and CDT 10 min. The results showed that CT and ODTFIS are the most and the less effective factors on response, respectively.  相似文献   

20.
Natural fibers are largely divided into two categories depending on their origin: plant based and animal based. Plant based natural jute fiber reinforced polypropylene (PP) matrix composites (20 wt% fiber) were fabricated by compression molding. Bending strength (BS), bending modulus (BM), tensile strength (TS), Young’s modulus (YM), and impact strength (IS) of the composites were found 44.2 MPa, 2200 MPa, 41.3 MPa, 750 MPa and 12 kJ/m2, respectively. Animal based natural B. mori silk fiber reinforced polypropylene (PP) matrix composites (20 wt% fiber) were fabricated in the same way and the mechanical properties were compared over the silk based composites. TS, YM, BS, BM, IS of silk fiber reinforced polypropylene composites were found 55.6 MPa, 760 MPa, 57.1 MPa, 3320 MPa and 17 kJ/m2 respectively. Degradation of composites in soil was measured upto twelve weeks. It was found that plant based jute fiber/PP composite losses its strength more than animal based silk fiber/PP composite for the same period of time. The comparative study makes it clear that mechanical properties of silk/PP composites are greater than those values of jute/PP composites. But jute/PP composites are more degradable than silk/PP composites i.e., silk/PP composites retain their strength for a longer period than jute/PP composites.  相似文献   

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