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1.
It has been considered that malic acid,α-hydroxy succinic acid, could not form crosslinks in the cellulosic materials unless activated by other polycarboxylic acids
such as butanetetracarboxylic acid or citric acid because there are only two carboxylic acids per molecule available for the
formation of one anhydride intermediate. However we found that the dicarboxylic malic acid with sodium hypophosphite catalyst
without the addition of other crosslinkers was able to improve wrinkle resistance of cotton up to 294° (dry WRA) and 285°
(wet WRA), which is a measure of crosslinking level in cotton.1H FT-NMR, FT-IR and GPC analysis indicated the in-situ formation of an trimericα, β-malic acid with a composition of 1:3 through the esterification between hydroxyl group and one of carboxylic groups in malic
acid during curing. The crosslinking of cotton was attributed to the trimericα, β-malic acid, a tetracarboxylic acid, which can form two anhydride rings during curing. The influence of crosslinking conditions
such as concentrations of malic acid and catalyst, pH of the formulation bath, and curing temperature were investigated in
terms of imparted wrinkle resistance and whiteness. The addition of reactive polyurethane resin in the formulation slightly
increased the mechanical strength retention of crosslinked fabric coupled with additional increase in wrinkle resistance. 相似文献
2.
We studied eight carboxylates as potential catalysts for the cellulose cross-linking with 1,2,3,4-butanetetracarboxylic acid (BTCA) and compared them with sodium hypophosphite (SHP). The results showed that the fabrics treated with sodium formate (SF) exhibited the highest wrinkle recovery angle (WRA) among the selected carboxylates, nearly equivalent to the WRA of the fabrics treated with SHP. We compared the radii and relative concentration ratios of different carboxylates anions, and found that SF had a particular amount of anions in the optimum pH range of the BTCA finishing bath, and had the smallest anion radius, both of which accounted for the higher WRA. The SF anions were present throughout the curing process. Based on the thermogravimetric analysis curves of SF and SHP, SF significantly decreased the temperature of the anhydride formation. In addition, the FTIR spectra displayed a stronger ester absorbance of the fabrics treated with BTCA/SF than those treated only with BTCA, which confirmed that SF accelerated the esterification between BTCA and cellulose. 相似文献
3.
The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent
were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium
chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven
the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA)
and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced
better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition. 相似文献
4.
Aluminum ammonium sulfate was used as a new catalyst for glyoxal to minimize the decrease of physical properties of durable
press cotton fabrics, and the optimum treatment conditions such as the concentration of glyoxal, molar ratio of catalyst to
glyoxal, curing temperature and time were investigated. The retention of tensile strength and the whiteness of fabrics treated
with glyoxal/aluminum ammonium sulfate was increased as much as to the degree of that obtained with glyoxal/aluminum sulfate
while wrinkle recovery angles were as good as those of the latter. Some additives such as DEG, polyurethane and softener were
used to improve the physical properties. When DEG or polyurethane was added to the glyoxal padding solution, wrinkle recovery
angle (WRA) significantly increased while tensile strength and whiteness were not influenced. DEG added to the glyoxal padding
solution increased the durability of DP finish. The softener added to the glyoxal padding solution increased the WRA of treated
fabrics while it decreased the tensile strength slightly. The whiteness of fabrics treated with glyoxal alone increased while
the WRA decreased slightly. 相似文献
5.
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
6.
There is currently much interest in natural compounds as bioactive functional components to replace synthetic functional agents in many industrial fields. This trend has also arisen in the textile industry. Phenolic compounds, existing in many fruits and vegetables, are a well-known group of secondary metabolites with a wide range of pharmacological activities. Thus, they have been attracting attention as part of the effort to realize environmentally friendly functional agents for textile finishing. In current research, cotton fabrics were treated with several phenolic compounds to transpose their beneficial characteristics onto clothing material. In particular, the treatment was conducted in two steps; the first to incorporate a crosslinker onto cotton cellulose, and the second to bond the phenolic compound to the crosslinker already anchored onto the cotton fabrics. A more efficient textile treatment was expected after employing the two-step process. After the finishing process, the cotton fabrics treated with phenolic compounds were investigated by FT-IR, SEM, an antibacterial test, and an antioxidant test. It was discovered that cotton fabrics treated with the two-step process showed >99.9 % of antibacterial ability and >80 % of antioxidant ability, even at lower concentrations of the crosslinker and phenolic compounds compared to those in earlier work. 相似文献
7.
Akbar Khoddami Shima S. Shokohi Mohammad Morshed Dariush Abedi 《Fibers and Polymers》2011,12(5):635-641
Textiles, especially those made of natural fibers, are suitable medium for the growth of microorganisms which causes disease
transmission, stink, colorful spots, and reduction in fabric strength. This research focuses on the antimicrobial finishing
of cotton fabrics using colloidal solution of silver nanoparticles. Due to the difficulties of adding a new step to the finishing
process of cotton textiles, efforts have been made to combine the antimicrobial treatment with the conventional finishing
processes. For this purpose two chemical finishes of Fixapret ECO as a crosslinking agent and Cellofix ME as a resin former
have been used in anti crease finishing of cotton fabric and their effects were evaluated. The properties of the samples have
been investigated by measuring the resistant of samples against bacteria, crease recovery angle, abrasion, and washing fastness.
The results showed that treated samples by pad-dry method have the best antibacterial effect with a direct relation between
the increase in drying temperature and antibacterial properties. However, the washing and abrasion fastness were not at the
acceptable level. Co-application of the colloidal solution of silver nanoparticles with the crease resistant materials improved
both fastness properties while at the same time limited the direct contact between the nanoparticles and the bacteria so the
antibacterial efficiency was reduced. Subsequently, it was concluded that the antibacterial finishing method should be selected
according to the end uses. In addition, antibacterial treatment could be one of the multi-purpose finishes for cotton fabric. 相似文献
8.
Low molecular weight copolymers of maleic anhydride and vinyl acetate were prepared to develop formaldehyde free cross-linking
agents. Since lower molecular weight is favorable for efficient penetration of the finishing agent into the cotton fibers
in the padding process, the concentration of the initiator, chain transfer agent and the monomer ratios were varied to obtain
copolymers of low molecular weights. The prepared polymers were characterized by GPC,1H-NMR, FTIR, DSC and TGA. Copolymers of molecular weights of 2 000 to 10 000 were obtained and it was found that the most
efficient method of controlling the molecular weight was by varying the monomer ratios. Poly(maleic anhydride-co-vinyl acetate)
did not dissolve in water, but the maleic anhydride residue hydrolyzed within a few minutes to form poly(maleic acid-co-vinyl
acetate) and dissolved in water. However, the maleic acid units undergo dehydration to form anhydride groups on heating above
160 °C to some extent even in the absence of catalysts. The possibility of using the copolymers as durable press finishing
agent for cotton fabric was investigated. Lower molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers were more
efficient in introducing crease resistance, which appears to be due to the more efficient penetration of the crosslinking
agent into cotton fabrics. The wrinkle recovery angles of cotton fabrics treated with poly(maleic anhydride-co-vinyl acetate)
copolymers were slightly lower than those treated with DMDHEU and were higher when higher curing temperatures or higher concentrations
of copolymer were used, and when catalyst, NaH2PO2, was added. The strength retention of the poly(maleic anhydride-co-vinyl acetate) treated cotton fabrics was excellent. 相似文献
9.
Study of antimicrobial activity of aloevera, chitosan, and curcumin on cotton, wool, and rabbit hair 总被引：1，自引：0，他引：1
Aloevera, chitosan, and curcumin were applied in alone and in combination with each others on cotton, wool and rabbit hair
by exhaustion method for the assessment of their antimicrobial activity. The antimicrobial activity of these natural ingredients
was better in peroxide treated cotton, formic acid treated wool/rabbit hair fibrous substrates than their corresponding intact
ones. Aloevera shown better antimicrobial activity than chitosan and curcumin when applied alone and its antimicrobial activity
was enhanced by addition of both chitosan and curcumin. The application of aloevera+chitosan+curcumin combination on peroxide
treated cotton and formic acid treated wool/rabbit hair fibrous substrate was fast up to twenty five washing cycles. 相似文献
10.
In this research, a novel cotton fiber with a silk fibroin (SF) coating was prepared by the oxidation of a cotton thread with
sodium periodate and subsequent treatment in a solution of silk fibroin. The structures of both the oxidized cotton samples
and the SF modified cotton samples were investigated by Fourier transform infrared (FT-IR) in combination with X-ray photoelectron
spectroscopy (XPS) analysis. Other performances such as surface morphology and breaking strength were also studied. The results
indicated that the weight of the oxidized cotton samples increased during SF treatment, while that of the un-oxidized cotton
(pure cotton) samples reduced after SF treatment. Compared with the pure cotton samples, the oxidized cotton clearly showed
a characteristic absorption band at 1730 cm−1 due to the stretching vibration of the C=O double bond of the aldehyde group. After being treated with the SF solution, the
oxidized cotton fiber showed a weakened characteristic absorption band at 1730 cm−1 and a new absorption band at round 1540 cm−1, suggesting the formation of C-N bond between aldehyde groups in the oxidized cotton and primary amines in the silk fibroin.
The results were also confirmed by XPS analysis. Compared with the oxidized cotton samples, the SF treated cottons had relatively
smooth surfaces, similar breaking strength, and the improved wrinkle recovery angles. The results in this research suggest
that cotton based materials with protein coating can be achieved without using any other crosslinking agents by the method
introduced. 相似文献
11.
Enzymes as silage additives. 1. Silage quality, digestion, digestibility and performance in growing cattle 总被引：5，自引：0，他引：5
Four grass silages were made from perennial ryegrass ensiled after a 1h wilt in 2-t silos without additive application, with application of formic acid or with one of two enzyme mixtures of hemicellulases and cellulases (enzyme 1 and enzyme 2). Effluent losses were monitored over the ensiling period (130 d).
Analyses of the silage showed that formic acid-treated silage had lower concentrations of lactic acid than the other silages. Both enzyme-treated silages had lower levels of cellulose, acid detergent fibre (ADF) and neutral-detergent fibre (NDF) than the untreated and formic acid treated silages. Effluent production was highest with enzyme-treated silages.
The silages were subsequently fed to growing steers equipped with rumen cannulae and T-piece duodenal cannulae. Apparent whole-tract digestibilities of organic matter constituents were significantly lower ( P < 0·05) with both enzyme-treated silages (untreated; 0·736, formic acid; 0·722, enzyme 1; 0·694, enzyme 2; 0·703). Both untreated and enzyme 2-treated silages sustained higher nitrogen digestibilities (g g−1 intake) (untreated; 0·675, formic acid; 0·636, enzyme 1; 0·630, enzyme 2; 0·662) and N retentions (g d−1 ) untreated; 16·0, formic acid; 14·0, enzyme 1; 11·6, enzyme 2; 16·6), but none of these differences was significant. When formic acid-treated silage was offered, there was a greater amount of organic matter apparently digested in the rumen (ADOMR). Non-ammonia nitrogen and microbial nitrogen flows at the duodenum were similar on all diets. The efficiency of microbial protein synthesis was highest with enzyme 2-treated silage and lowest with formic acid-treated silage (untreated, 35·4; formic acid, 25·2; enzyme 1, 30·4; enzyme 2, 39·4), but none of these differences were significant. 相似文献
Analyses of the silage showed that formic acid-treated silage had lower concentrations of lactic acid than the other silages. Both enzyme-treated silages had lower levels of cellulose, acid detergent fibre (ADF) and neutral-detergent fibre (NDF) than the untreated and formic acid treated silages. Effluent production was highest with enzyme-treated silages.
The silages were subsequently fed to growing steers equipped with rumen cannulae and T-piece duodenal cannulae. Apparent whole-tract digestibilities of organic matter constituents were significantly lower ( P < 0·05) with both enzyme-treated silages (untreated; 0·736, formic acid; 0·722, enzyme 1; 0·694, enzyme 2; 0·703). Both untreated and enzyme 2-treated silages sustained higher nitrogen digestibilities (g g
12.
本研究通过对木薯根系分泌物进行提取、分离与鉴定,探究不同木薯品种根系分泌物的差异,为筛选抗化感耐连作木薯新种质提供参考。以木薯组培苗琼脂培养基为试验材料,采用正交试验设计,结合GC-MS技术考察不同萃取材料和洗脱剂对木薯根系分泌物的提取和分离效果,选择最优方案测定‘新选048’‘南植199’和‘华南205’的根系分泌物。结果表明：（1）木薯根系分泌物水溶性物质提取的最优方案为：用去离子水超声提取捣碎的琼脂培养基30 min,固液分离后用XAD-2萃取、无水乙醇洗脱,浓缩后用GC-MS检测,成功鉴定出包括有机酸类、醇类、酯类、酮类、醛类等26种有机化合物。（2）醇溶性物质提取的最优方案为：用50%乙醇超声提取捣碎的琼脂培养基30 min,固液分离后用XAD-4萃取、无水乙醇洗脱,浓缩后用GC-MS检测,鉴定出包括有机酸类、醚类、酯类、酮类、醛类等15种有机化合物。（3）不同品种根系分泌物的水溶性和醇溶性成分均有差异。‘南植199’根系分泌物的主要水溶性物质有羟乙酸甲酯（相对含量为3.72%）、羟基丙酮（2.40%）、甲肼（1.79%）等,主要醇溶性物质有乙醇醛（18.89%）、羟基丙酮（2.47%）、甲酸（2.25%）等;‘新选048’的主要水溶性物质有甲酸（2.68%）、1,5-戊二醇（2.39%）、丙烯酸羟乙酯（2.01%）等,主要醇溶性物质有乙醇醛（17.00%）、甲酸（2.62%）、羟基丙酮（2.46%）等;‘华南205’的主要水溶性物质有甲酸（2.23%）、羟基丙酮（1.80%）、羟乙酸甲酯（1.43%）等,主要醇溶性物质有乙醇醛（16.58%）、甲酸（3.06%）、八氟戊醇（2.98%）等。不同木薯品种的根系分泌物种类和含量均有差异,从而导致其抗化感耐连作能力的差异,为筛选耐连作品种缓解木薯连作障碍成为可能。 相似文献
13.
Cotton fabric was treated with montmorillonite (MMT) so as to evaluate its effectiveness on improving its wrinkle resistance.
The MMT in emulsion form was applied to cotton fabric by padding and finally the wrinkle resistance of the MMT-treated cotton
fabric was improved. Furthermore, instrumental methods were used for studying the presence of MMT particles on the cotton
fabric surface. It was noted that nano-scale MMT particles adhered on the fiber surface and the particle size played an important
role in influencing the wrinkle resistance of the cotton fabric. The experimental results are discussed thoroughly in this
paper. 相似文献
14.
Perennial ryegrass, harvested as second-cut material on 10 and 11 July 1990, was treated with either formic acid at 31 t-1 or an acid-salt type additive at 61 t-1 and ensiled in roofed 150 t bunker silos. Subsequently both silages underwent a predominantly lactic fermentation. Nevertheless the acid-salt-treated silage had a significantly higher quantity of formic acid (19 vs 12 g kg DM-1 ) and significantly lower levels of lactic (98 vs 118 g kg DM-1 ) and acetic acid (11 vs 17 g kg DM-1 ) compared with formic acid-treated silage. In-silo losses and effluent production were similar.
Each silage was individually fed to 10 October-calving Friesian dairy cows (average weight 565 kg) from weeks 2 to 15 of lactation, together with 3 kg d-1 of a compound feed containing 190 g kg DM-1 crude protein and with an estimated metabolizable energy content of 12·6 MJ kg DM-1 . The acid-salt additive had no significant effect on silage DM intake, daily milk yield, milk protein or cow liveweight change, but significantly increased milk butterfat content compared with formic acid-treated silage.
It is concluded that the acid-salt type additive produced little difference in terms of either silage fermentation or animal performance compared with formic add treatment. 相似文献
Each silage was individually fed to 10 October-calving Friesian dairy cows (average weight 565 kg) from weeks 2 to 15 of lactation, together with 3 kg d
It is concluded that the acid-salt type additive produced little difference in terms of either silage fermentation or animal performance compared with formic add treatment. 相似文献
15.
In the presence of Pt catalyst, α,ω-hydrogenpolysiloxane reacted with allyl glycidyl ether, and an intermediate α,ω-diepoxysiloxane was formed. The epoxy cyclic-opening reaction was conducted between the intermediate and polyetheramine in isopropanol solution, the silicone polyetheramine block copolymer (BPEAS) was thus made. The chemical structures of BPEAS were characterized using IR and 1H-NMR separately. Then cotton fabric was treated with BPEAS for application purpose. The finishing effects were tested in terms of film morphology, hydrophilic ability, softness and mechanical properties. The recorded results showed that BPEAS can be used directly to treat cotton fabrics without adding any emulsifier at the viscosity of 6700 mPa·s and amino value of 0.6009 mmol/g. Bending rigidity and hysteresis of the treated fabric decreased by 53.53 % and 67.39 %, the drape coefficient dropped by 15 %, whereas the wrinkle recovery angle increased by 57.14 %. The treated cotton fabric is hydrophilic, and has a bulky soft hand, better anti-wrinkle property compared to the untreated one. 相似文献
16.
Nabil A. Ibrahim El-Amir M. Emam Basma M. Eid Tawfik M. Tawfik 《Fibers and Polymers》2018,19(4):797-804
A new approach for an eco-friendly multi-functionalization of cotton/wool (C/W) and viscose/wool (V/W) blended fabrics was investigated. In this study, Ag-nanoparticle (Ag-NP) and/or ZnO-nanoparticle (ZnO-NP) functional agents were incorporated into the finishing bath along with citric acid (CA) or succinic acid (SA) as ester-crosslinking or esterifying agent, and sodium hypophosphite catalyst using the padding technique. The obtained results indicated that the extent of multi-functionalization expressed as antibacterial activity, UV-blocking functionality and wrinkle recovery ability were determined by kind of nanomaterial, nature of carboxylic acid, i.e., bi- or tri-functional and type of substrate. The results also demonstrated that blended fabrics finished with Ag-NP/ZnO-NP/CA/SHP nano-finishing formulation exhibited outstanding durable multi-functional properties even after 10 washing cycles. In addition, the change in surface morphology and the existence of Ag and/or Zn onto the selected V/W fabric surfaces have been confirmed by SEM and EDX analysis respectively. 相似文献
17.
Measuring and characterizing fabric wrinkling objectively and accurately is of vital importance because wrinkling behavior is one of the most important factors to determine visual aesthetic of fabrics and clothes. In this paper, a novel method for multidirectional fabric wrinkling measurement is presented. 12 fabrics with different fiber contents and weave structures are prepared and wrinkled by the new method. GLCM variables and standard deviation of wavelet decomposition coefficients are used to characterize fabric wrinkling. Results show that WRA (wrinkle recovery angle) does not have significant linear correlation with the GLCM variables (energy, entropy, contrast and correlation). The wavelet coefficient standard deviation at level 6 has the highest correlation with average WRA. The equations between average WRA and standard deviations can be used to predicate average WRA of a fabric conveniently, avoiding the time-consuming and tedious testing of WRA in each direction. 相似文献
18.
In this study, a facile method was developed to coat AgCl nanoparticles (NPs) onto knitted cotton fabrics. The AgCl NPs were characterized by ultraviolet absorption spectrum, X-ray diffraction (XRD) and dynamic laser light scattering (DLS). The AgCl NPs were coated onto cotton fabrics through a pad-dry-cure process with the assistance of 1,2,3,4- butanetetracarboxylic acid (BTCA). Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), ICP-OES analysis and energy-dispersive X-ray spectroscopy (EDX) confirmed that AgCl NPs were successfully coated onto cotton fabrics. The prepared cotton samples exhibited excellent antimicrobial activity against both Gram-positive S. aureus and Gram-negative K. pneumonia bacteria. Rat skin fibroblast cytotoxicity testing demonstrated the treated cotton fabrics to be non-toxic. The washing durability evaluation showed that the antimicrobial function of cotton fabrics was durable to washing. In addition, the wrinkle resistance of the coated cotton fabrics was improved and there was no obvious change in whiteness. 相似文献
19.
Maleic acid (MA) and itaconic acid (IA) used as crosslinking agents for cotton fabrics are more cost-effective than the most efficient nonformaldehyde crosslinker 1,2,3,4-butanetetracarboxylic acid (BTCA), but poor stability of finishing bath and fabric yellowing are the main disadvantage of MA/IA in situ polymerization and crosslinking system. In this research, the application performance improvement of MA/IA crosslinking system for cotton fabrics was studied. Replacement of the widely used sodium hypophosphite (SHP) with potassium hypophosphite (PHP) as catalyst allowed for obtaining a stable finishing bath under ambient temperature and led to improved final durable press (DP) performance of the treated fabrics. The influences of PHP concentration, curing temperature, and curing time on the performance of finished fabrics were investigated. Cotton fabrics treated by MA/IA/PHP crosslinking system exhibited comparable DP performance and laundering durability to that finished with BTCA. To address the fabric yellowing problem, the residual MA and IA attached on the treated fabrics by single-ended ester linkage was determined by HPLC. The data indicated that the degree of fabric yellowing was linearly related to the unpolymerized carboxylic acid MA and IA concentration on the treated fabrics. Several approaches were explored to improve the whiteness of MA/IA/PHP crosslinked fabrics. It was found that steam drying with 30-50 % humidity could effectively improve fabric whiteness. The findings of this study have significant implications for better application of unsaturated polycarboxylic acids in crosslinking of cellulose. 相似文献
20.
Effects of formic acid and potassium diformate on the fermentation quality,chemical composition and aerobic stability of alfalfa silage 
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下载免费PDF全文 The objective of this study was to evaluate the efficacy of potassium diformate (KDF) as a potential additive for alfalfa silage. Fresh alfalfa was untreated or treated with formic acid (4 g/kg fresh weight, FW) or three concentrations of KDF (4, 5.5 or 7 g/kg FW). After 60 days of ensiling, the addition of formic acid and greater levels of KDF (5.5 and 7 g/kg) effectively reduced silage pH and inhibited the undesirable bacteria, indicated by lower butyric acid, ethanol, ammonia N concentrations and microbial populations (including enterobacteria, yeasts, moulds and clostridia). Additives decreased the dry‐matter loss, and more water‐soluble carbohydrates were preserved in the silages with formic acid or potassium diformate than in the control. Alfalfa silages treated with formic acid at 4 g/kg FW or potassium diformate at 5.5 or 7 g/kg FW were classified as the highest quality silage based on the higher Flieg's point (above 70) and remained stable for more than 9 days during aerobic exposure. Potassium diformate is recommended as an effective additive for alfalfa silages at a level of 5.5 or 7 g/kg FW under the humid and hot conditions of southern China. 相似文献