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1.
N-halamine precursor 2,2,6,6-tetramethyl piperidinol (TMP), a hindered amine light stabilizer, was bonded onto cotton fabric by using 1,2,3,4-butanetetracarboxylic acid (BTCA) as a crosslinking agent. A variety of treating conditions including TMP concentration, curing temperature and time, and catalyst were studied. The treated fabrics were characterized using FTIR spectra and scanning electron microscope (SEM). The cotton fabric treated with TMP precursor could be rendered biocidal upon exposure to dilute household bleach. The chlorinated cotton swatches showed great efficacy and inactivated 100 % of Staphylococcus aureus with 7.1 log reduction with 5 min of contact and 83.25 % of E. coli O157:H7 at 10 min of contact. In addition, the wrinkle recovery angle of the treated cotton fabrics increased from 229 ° of untreated cotton fabrics to 253 °. This study provided a practical finishing process to produce cotton fabrics with easy care and antibacterial functionalities at the same time.  相似文献   

2.
Natural dye extracts were obtained by extraction from Punica granatum L. using water as an extractant at 90 °C for 90 min with various liquor ratios (solid Punica granatum L.(wt.): solvent water(wt.); 1:100–1:5). Dyeing was carried out using a 1:50 dyeing bath ratio at 80 °C for 60 min by exhaustion method. This study focused on the effect of liquor ratio on dyeing properties and deodorizing/antibacterial performance of various fabrics (cotton, silk and wool) dyed with Punica granatum L. extract without mordants. The optimum liquor ratio was found to be 1:10. By IR, UV-visible spectroscopies and HPLC analysis, the main component in Punica granatum L. extract and the yellow colorant component were found to be ellagic acid. By GC/MS analysis, the major volatile components of pristine Punica granatum L. powder were found to be acetic acid (area: 25.84 %), ethanol (area: 17.97 %), acetoin (area: 13.11 %), acetaldehyde (area: 8.96 %), isobutanal (area: 4.90 %). All dyed fabrics (cotton, silk and wool fabrics) displayed outstanding deodorizing performance (99 %) against ammonia gas and excellent antibacterial performance (bacteriostatic reduction rate: 99.9 %) against Staphylococcu aureus and Klebsiella pneumoniae.  相似文献   

3.
Our study proposes an enzymatic scouring method for cotton fabrics using the enzyme cutinase. We established cutinase treatment conditions for cotton fabrics from their relative activity at different pH levels, temperatures, enzyme concentrations, and treatment times. Weight loss, moisture regain, K/S value, tensile strength, and SEM micrographs of cotton fabrics were analyzed. We determined the optimum cutinase treatment conditions to be as follows: pH of 9.0, temperature of 50°C, cutinase concentration of 100 %, and a treatment duration time of 60 min. We discovered that this cutinase treatment hydrolyzed the cuticle of cotton fabrics. The cutinase treatment did not decrease the moisture regain and the K/S value. The optimum concentrations of Triton X-100 and calcium chloride, which were used as auxiliaries for cutinase treatment, were found to be 0.5 % (v/v) and 70 mM, respectively. Some cracks were observed on the surface of the cotton fibers; however, the tensile strength did not decrease.  相似文献   

4.
The efficacy of antimicrobial treatment of cotton fabrics depends on various parameters of the coating process, such as the chemical nature and concentration of the antimicrobial agent, the composition of the crosslinking formulation, and the curing temperature. The inclusion complex of triclosan with β-cyclodextrin (βCD) was synthesized and characterized by FTIR, XRD, NMR, Raman, SEM, and TGA. The minimum inhibitory concentration and minimum bactericidal concentration of the complex against Klebsiella pneumoniae and Staphylococcus aureus were compared to those of its precursor. A multifactorial study included an evaluation of the effects of triclosan complexation with β-cyclodextrin, a comparison between the glyoxal and tetracarboxylic acid as crosslinkers, an investigation of the effect of crosslinker and catalyst concentrations, and a comparison of curing at 120°C and 180°C. The cotton was characterized by FTIR-ATR, the micrographs of treated samples were obtained by SEM and the weight add-on was calculated. The bactericidal properties were determined according to AATCC-147. The correlation between the coating process parameters and the antimicrobial efficacy was determined. The optimal combination leading to the highest weight add-on and the antimicrobial coating that was most durable to multiple detergent washes at an elevated temperature was the use of complexed triclosan grafted onto the cotton in the presence of tetracarboxylic acid, followed by curing at 180°C. The curing temperatures were 120°C (P=0.002) and 180°C (P=0.008), catalysts were 1 % and 2 % aluminium sulfate and sodium hypophosphite (P<0.001), and the crosslinkers were 5 % and 10 % glyoxal and butanetetracarboxylic acid (P<0.001); these parameters significantly enhanced the antimicrobial properties of the treated fabrics. The study showed that βCD did not have antimicrobial activity, while the βCD/triclosan-treated textile exhibited potential antimicrobial properties. Overall, the bactericidal activity of fabrics can be enhanced by using βCD/triclosan with 10 % butanetetracarboxylic acid as a cross-linker and 5 % sodium hypophosphite as a catalyst at a curing temperature of 180°C.  相似文献   

5.
《Plant Production Science》2013,16(3):232-237
abstract

The effects of various constant temperatures (4, 9, 14, 19, 24, 29, 34, and 38°C) on the germination of winter wheat seed ( Triticum aestivum L. cv. ‘Koyuki’) in a dark condition were studied. The maximum germination percentage was 98% at 24°C. The speed of germination was fastest at 29°G. These results indicate that the most suitable temperature for germination was in the range of 24 to 29°G. α-Amylase expression during germination was also high at higher temperature, and maximum expression occurred at 29°C, although a high temperature of 38°C prevented the synthesis of α-amylase. The close correlation between germination and α-amylase activity at various temperatures indicates that α-amylase is an essential factor for the temperature-dependent germination of wheat seed. In contrast, accumulation of proline increased at a lower temperature, and was the highest at 4°G. We also studied the effects of gibberellin (GA3) and proline, a compatible osmotica in alleviating the effect of low and high temperature stresses. Pre-soaking treatment with GA3 and proline was effective in promoting germination and increasing α-amylase expression at a low (4°C) and high (38°C) temperature. These results suggest that GA3 and proline exhibit positive effects on stress alleviation through the stimulation of α-amylase expression.  相似文献   

6.
This study evaluated the potential application of an atmospheric plasma (AP) treatment as a pre-treatment for digital textile printing (DTP) of polyester (PET) fabrics and cotton, in order to determine its viability as an alternative to the usual chemical treatment. The surface properties of the AP-treated fabrics were examined through scanning electron microscopy (SEM) and contact angle, and the physical properties, such as electrostatic voltage and water absorbance, were tested. The properties of cotton and PET with the AP treatment were found to be dependent on number of repetitions and electric voltage. Although no remarkable surface differences were observed by SEM in the fabrics before and after treatment, the static contact angle of the PET after AP treatment was decreased from 85 ° to 24 ° at wave. In addition, the charge decay time decreased as the voltage and number of treatments increased. The absorption height of PET changed after exposure to 7 mm with increasing measurement time. The K/S with and without the AP pre-treated and DTP finished cotton was better than that with the usual chemical modification. In PET, the 0.5 kW and 1 time AP-treated specimen showed the highest K/S values.  相似文献   

7.
Nano-TiO2 based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO2, nano polyurethane/TiO2, and TiO2/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO2 based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined.  相似文献   

8.
The pasta protein network limits starch hydrolysis rate in vivo leading to low post-prandial glycemia. To better understand the mechanisms involved, various pasta products were processed to obtain protein network structures differing from that in reference pasta extruded at 40 °C and dried 17 h at 55 °C. After cooking, pasta strands were submitted to in vitro alpha -amylolysis. Compared to reference pasta, higher extrusion temperature (70 °C), high-temperature drying treatment (2 h at 90 °C) or autoclaving (115 °C for 15 or 40 min) had no marked effect on the rate of dextrin release from pasta particles. Protein enrichment at a 20%-level and flour fractionation-reconstruction with removal of insoluble fibre before pasta extrusion significantly (p<0·05) delayed (≥1 h) the rate of dextrin release (−14% at 8 h). Confocal laser scanning microscopy allowed the three-dimensional structure of the protein network from protein-enriched pasta to be observed, and suggested that increased starch encapsulation may explain the reduced accessibility of starch to alpha -amylases. A stronger cohesiveness between starch and protein, due to insoluble fibre removal, was probably responsible for the decrease of starch accessibility to alpha -amylase in fractionated-reconstructed flour pasta. Modified geometrical characteristics (e.gtortuosity) of the protein network were not correlated with starch degradation rates.  相似文献   

9.
A novel method was developed to prepare the antibacterial cotton fabrics through in situ deposition of silver nanoparticles on the cotton fabrics by the reduction of Ag+ without any reductant and dispersant. The data showed that by immersing the cotton fabrics in 160 mM AgNO3 solution at 90 °C, the amount of silver nanoparticles was increased from 0.6890 to 1.3561 mg per gram of fabrics with the increase of reaction time from 10 to 50 min. The obtained cotton fabrics showed excellent antibacterial activity and laundering durability, in which the bacterial reduction was still 98.5 and 94.3 % to Escherichia coli and Staphylococcus aureus, respectively, even after the fabrics were washed for 20 cycles. Thus, this facile in stitu reduction method without any other reducers or stabilizers may bring a promising and green strategy to produce functional cotton fabrics.  相似文献   

10.
N-methylol dimethylphosphonopropionamide is a flame-retardant agent commonly combined with melamine resin and phosphoric acid catalyst to impart flame-retardant property to cotton fabrics. A co-catalyst titanium dioxide (TiO2) is added into the formulation in order to improve the flame-retardant performance by enhancing the crosslinking reaction and physically attaching on to cotton fabrics. The fabrics cured at temperature of 150 °C and 170 °C have a better flame-retardant ability and can withstand multiple times of home laundering compared with those cured at temperature of 110 °C and 130 °C. The flame-retardant ability is further enhanced by treating the fabrics in the presence of TiO2. In addition, the low stress mechanical properties measured by Kawabata Evaluation System for Fabric (KES-F) are altered after flame-retardant treatment. These changes are contributed by the formation of crosslinks after treatment, acid-catalyzed depolymerization in a strong acidic medium and the presence of co-catalyst TiO2. In addition, the properties of cotton fabrics depend greatly on the choice of curing temperature. High curing temperature usually caused poor hand properties of the fabrics due to the extensive crosslinks formation. Lastly, the existence of TiO2 in the treatment not only improves the reaction efficiency but also has positive enhancement with respect to compressional recovery ability and tensile properties.  相似文献   

11.
The wool fabrics were treated by ultraviolet (UV) radiation and then dyed with Camellia sinensis (L.) O. Ktze var. waldensae (S.Y.Hu) Chang (yellow-bud tea) extract using meta-mordant dyeing method. The results indicated that the hydrophilicity of wool fabrics was improved after UV radiation treatment, which was conducive in improving color performance for the meta-mordant dyeing with yellow-bud tea extract of wool fabrics. The optimal dyeing process was that the powdered extract (5.0 % o.w.f) and the CuSO4 (2.0 % o.w.f) were added to the dyeing liquor, the pH value was adjusted to 3.5-4.0 by HCOOH, the wool fabrics treated by UV radiation for 10 min and then were dyed at a bath ratio of 1:50 under 95 °C for 70 min. By means of three-factor quadratic current rotation revolving design (TQCRRD) method, the computation results of the mathematical equations and models indicated that UV radiation was the most important factor for meta-CuSO4 dyeing with yellow-bud tea extract for wool fabrics.  相似文献   

12.
《Plant Production Science》2013,16(2):110-116
Abstract

Germination percentages of wheat grains sampled at 3 grain-filling stages : yellow-ripe stage (water content 45-50%), dough-ripe stage (35-40%), and full-ripe stage (25-30%), and imbibed in water at 12°C and 20°C were examined in relation to the activities of α-amylase and endoprotease. Wheat varieties studied were Chihoku-komugi, which is susceptible to pre-harvest sprouting, and Satanta, which is resistant. Germination percentage was higher at 12°C than at 20°C in all grains sampled at all stages in both varieties, and was higher in Chihoku-komugi than in Satanta at 20°C. The activity of α-amylase in the grains at the yellow-ripe stage was higher at 12°C than at 20°C in both varieties, but that at the other 2 stages was higher only in Satanta. Endoprotease increased rapidly from 7 to 10 days after the start of imbibition, and exceeded 12 units only at 12°C in Chihoku-komugi grains at the dough and full-ripe stages. The results showed that α-amylase activity was lower than the value equivalent to 300 brabender unit (BU) in amylography when the germination percentage was 0%. Endoprotease activity exceeded 6 units when the germination percentage exceeded 90%.  相似文献   

13.
A flexible and stretchable three-dimensional nanocomposite membrane based on traditional cotton fabric is a promising alternative for proton exchange membrane because it has the capability of transferring protons, is inexpensive, and also have higher current density compared to Nafion membranes in microbial fuel cells. The obtained results showed that the highest power and current of PVAc-g-PVDF-coated cotton fabric were 400±10 mW/m2 and 92 mA/m2, respectively. However, maximum generated power and current for Nafion-117 were 300±10 mW/m2 and 60 mA/m2, respectively. The highest proton conductivity of PVAc-g-PVDF-coated cotton fabric was (1.5±0.2)×10-2 S/cm at 25 °C and lowest glucose permeability was (12±1)×10-6 cm2/s after Mg2+ ions adsorption. Furthermore, the highest COD removal (85±3 %) and CE (11.2 %) were obtained from PVAc-g-PVDF-coated cotton fabric. The coated cotton fabric can provide a novel route for low-cost production of high-performance flexible proton exchange materials from the natural fabrics.  相似文献   

14.
The goal of this study was to establish optimal conditions for improving the hydrophilicity of polyester fabrics. The hydrolytic activity of papain was determined by measuring the number of carboxylic groups in the treatment solution. Papain treatment conditions-such as pH, temperature, treatment time, and enzyme concentration-were optimized by measuring hydrolytic activity, moisture regain, and wettability. Optimal papain treatment conditions were identified as a pH of 7.5, temperature of 30 °C, treatment time of 60 min, and papain concentration of 100 %(o.w.f.). The moisture regain for polyester fabrics treated with papain improved to 1.28±0.02 %, a 2.7-fold increase compared to that of untreated polyester fabrics. As the hydrolytic activity increased, the moisture regain and wettability of the treated fabrics improved. L-cysteine and sodium sulfite did not affect the moisture regain of papain-treated polyester fabrics.  相似文献   

15.
The paper discusses a method to functionalize cotton fabrics using biologically active natural compounds to achieve the antibacterial characteristics required for medical application. The biologically active natural compounds include propolis, beeswax, and chitosan. Three 100 % cotton knitted fabrics with different degrees of compactness were impregnated in the emulsions containing the active ingredients and fabric variant G3 with the highest degree of impregnation was considered for the evaluation of the antibacterial properties and comfort characteristics. The results show that the treated cotton fabric had high antibacterial activity against both gram positive bacteria Staphylococcus aureus and Streptococcus β haemolytic, and gram negative bacteria Escherichia coli and Pseudomonas aeruginosa. The presence of the biologically active natural compounds on the cotton substrates modified the surface of the textile fibers as seen in the SEM images. The treatment also improved fabric comfort properties, the cotton substrates became less air permissive and more hygroscopic after the treatment. The experimental results indicated that propolis, beeswax and chitosan can be applied as an emulsion to functionalize cotton textile materials. The antibacterial performance of the functionalized fabrics suggested that the cotton fabrics treated with those biologically active natural compounds have the potentials to be used in medical fields.  相似文献   

16.
Alkaline pectinases could be applied in the bioscouring for cotton textiles to improve the wettability of the fabric. In order to evaluate the bioscouring effect of cotton fabrics directly and simply, the relationship between the amount of products degraded by alkaline pectinase and the wettability of the fabric was established with spectrophotometry. The results showed that products degraded by an alkaline pectinase Bioprep 3000L exhibited one characteristic absorption peak at 239 nm, which indicated that unsaturated degradation products were yielded. During the bioscouring of the cotton fabrics, the increase of the amount of both unsaturated degradation products and reducing sugars released from the pectins existing in raw cotton fiber was consistent with the improvement of wetting property of the cotton fabrics with prolonging the treatment time.  相似文献   

17.
α,ω-di[(4-butoxy-piperazin-1-yl)-phosphinic acid methyl ether]-terminated linear polysiloxane (PNPDMS) was synthesized and utilized as the flame retardant and hydrophobing agent. The flame retardance and thermal decomposition behaviors of cotton fabrics were systematically estimated by limiting oxygen index (LOI), thermogravimetric analysis and vertical burning test, respectively. It was found that the LOI of cotton fabric treated with PNPDMS enhanced to 29.82 % compared with cotton fabric without treatment, whose LOI was only 18.00 %. The treated cotton fabric showed a shorter char length, a shorter After-flame time, and no After-glow time as revealed in vertical burning test. The mechanical property in treated cotton fabric was slightly decrease. Furthermore, the grade of water repellency of treated cotton fabric reached to 90 and water contact angle (WCA) increased to 141.90° compared with cotton fabric without treatment whose WCA was 62.80°. The result showed that the cotton fabric treated with PNPDMS exhibited excellent flame retardance and hydrophobic properties.  相似文献   

18.
UV curing of perfluoro-alkyl-polyacrylate resins able to impart water as well as oil-repellency to cotton fabrics was studied in comparison with conventional thermal polymerization. The process was assessed through weight gain and gel content measurements while the properties conferred to cotton fabrics were determined in terms of water and oil contact angles, moisture adsorption, and water vapor permeability. The polymerization yields were of the same order (>80 %) of those obtained with thermal curing as well as the high contact angles with water (>127°) and oil (>118°) even at low resin add-on (3 %). UV cured resins yielded oil contact angles mostly higher than 120° denoting super oil-repellent surfaces. Moreover the water and oil-repellency was adequately maintained after washing. The moisture adsorption of finished fabrics was lower than that of untreated cotton, but slightly higher for UV cured than thermally treated fabrics. Water vapor transmission rate showed that the finish treatment, thermal as well as by UV curing, does not reduce the breathability of the original cotton. DSC analysis demonstrated that the fiber pyrolysis is affected by the polymer add-on, while FTIR-ATR spectra of all finished fabrics showed typical peaks of ester and C-F groups. XPS analysis showed small differences between thermal and UV curing coatings with each resin, while coatings with the lowest percentage of fluorine groups did not affect the water and oil-repellency.  相似文献   

19.
Two functional compounds were successfully extracted from neem (Azadiracta indica): a tannin-rich natural dye and an antibacterial agent. The dye was extracted from the bark using water, and the antibacterial from the leaf using methanol. These were used to dye hemp fabrics. Higher color strength values (K/S) were found when dyeing was conducted at a higher dye concentration, elevated temperature, and longer dyeing time. Optimal results were achieved when using 5 %w/v of extracted powder at 100 °C for 60 min. The resulting fabrics appeared reddish-brown, and were rated as good to excellent for color fastness against washing, water, sea water, and perspiration. The antibacterial agent from the neem leaf was extracted by Soxhlet apparatus at 65 °C with methanol as solvent. The dyed and antibacterial-finished hemp fabrics were tested against Staphylococcus aureus, following the percentage reduction test of AATCC 100. The treated fabrics demonstrated a 99.99 % reduction in Staphylococcus aureus.  相似文献   

20.
A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.  相似文献   

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