Non-formaldehyde durable press finishing of dyed fabrics: evaluation of cotton-bound polycarboxylic acids

The polycarboxylic acids 1,2,3,4-butanetetracarboxylic acid and citric acid are used as nonformaldehyde durable press finishing agents instead of formaldehyde-releasing N -methylol compounds. In this study, isocratic HPLC is applied in an attempt to quantify the polycarboxylic acids that react with cellulosic material dyed with CI Reactive Red 195, CI Reactive Yellow 145 and CI Reactive Blue 221. Subsequently, the fabrics are cured with formulations containing butanetetracarboxylic acid and citric acid or a combination of both. The chromatographic determination reveals that an increase in the depth of shade results in a decrease of the amount of butanetetracarboxylic acid, except in the case when the cotton is dyed with CI Reactive Blue 221, a copper formazan complex-based dyestuff. Colour measurements indicate that the Δ E * values decrease in the order CI Reactive Yellow 145, CI Reactive Red 195 and CI Reactive Blue 221.     

Improving easy care nonformaldehyde finishing performance using polycarboxylic acids via precationization of cotton fabric

Cotton fabric were first subjected to quaternization (cationization) reaction using 3‐chloro‐2‐hydroxypropyl trimethyl ammonium chloride commercially known as Quat®‐188. Cationization was carried out under different conditions for optimization of the preparation of cationized cotton with different degrees of cationization, using the pad‐batch method. Also, established was the optimal condition for cationization that involves Quat‐188/NaOH molar ratio 1/2 at 70°C for 4 h. Besides, a thorough investigation of factors affecting reaction of these cationized cotton with citric acid (CA) or 1,2,3,4‐butanetetracarboxylic acid (BTCA) was carried out with a view of improving the ease of care characteristics of nonformaldehyde finishing. The dependence of fabric performance as measured by strength properties, dry wrinkle recovery angles, whiteness index, and dyeability with reactive dyes was also evaluated. It was postulated that reaction of cationized cotton with either CA or BTCA involves estercrosslinking as well as ionic crosslinking. This, indeed, was largely positively reflected on the fabric performance especially when the properties of both uncationized cotton were compared with those of the cationized cotton. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2697–2704, 2006     

Thermoanalytical characteristics of polycarboxylic acids investigated as durable press agents for cotton textiles

Polycarboxylic acids are of great interest to the cotton textile industry as durable press agents because they do not release substances that require mandatory monitoring. Differential scanning colorimetric (DSC), thermogravimetric (TG), and differential thermogravimetric (DTG) techniques were used to study the thermal characteristics of a series of 10 polycarboxylic acids. Samples included di-, tri-, and tetra-functional compounds some of which contained olefinic linkages, hydroxyl substituents, and cyclic structure. Thermogravimetric data at simulated fabric cure temperatures was used to assess the potential of a compound for use as a textile finishing agent. In high-temperature studies the compounds were readily distinguishable in DSC analyses. General characteristics such as increases in total heats of reactions were found to be related to the number of functional groups. These results also provided support for a mechanism for the reaction of polycarboxylic acids with cellulose through an anhydride intermediate.     

Thermoanalytical characteristics of durable press treated cotton fabrics

Thermoanalytical characteristics of chemically treated cotton fabric often appear similar to those of untreated cotton. The overwhelming amount of cotton cellulose versus the small quantities of finishing chemicals present can mask many features contributed by reactant. The current work is an initial attempt to detect and differentiate among a variety of durable press finishes. They include three N-methylol reactants, and four polycarboxylic acids with two alkali metal salts of phosphorus-containing acids used to catalyze their reaction with cellulose. Differential scanning calorimetric and thermogravimetric techniques were employed under dynamic nitrogen conditions. Changes in residue, rate of weight loss, peak intensity, and peak temperature were observed and varied with reactant, catalyst used, and washing. The ability to distinguish among polycarboxylic acids, catalysts, and/or other formaldehyde-based reactants is of value to the textile chemist. With these preliminary results, we may soon offer a new means of finish identification. © 1993 John Wiley & Sons, Inc.

1 This article is a US Goverment work and, as such, is in the public domain in the United States of America.

     

Durable press finishing of cotton with polycarboxylic acids. I. Preparation of thiosuccinyl-s-triazine

The preparation of an alternative polycarboxylic acid to replace the most promising, but expensive, crosslinking reagent 1,2,3,4-butanetetracarboxylic acid (BTCA) is reported. The reaction of mercaptosuccinic acid with 2,4,6-trichloro-s-triazine (cyanuric chloride) gave a dithiosuccinyl derivative. The preparation reaction was followed using horizontal ATR infrared spectroscopy and capillary electrophoresis. The final product was characterized by FTIR, capillary electrophoresis, and ¹H-NMR. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1465–1474, 1997     

Durable press finishing of cotton with polycarboxylic acids. II. Ester crosslinking of cotton with dithiosuccinic acid derivative of S-triazine

The preparation of an alternative polycarboxylic acid to replace the most promising but expensive crosslinking reagent butanetetracarboxylic acid (BTCA) was reported in Part I.¹ Part II studies the efficiency of the crosslinking of cotton with the dithiosuccinic acid derivative of s-triazine (HDTST). Diffuse Reflectance infrared (DR FTIR) spectroscopy in combination with wrinkle recovery angle measurements (WRA) were used to analyse the efficiency of cotton cellulose crosslinking. Energy Dispersive X-ray analysis (EDX) of the polycarboxylic acid-finished cotton fabric was performed to study sulphur distribution. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 171–177, 1997     

Catalyst effects found in thermal and mass spectrometric analyses of polycarboxylic acids used as durable press reactants for cotton

Effective polycarboxylic acids (PCAs) crosslink cotton cellulose by an ester linkage and smooth-drying fabrics are produced. The presence of a catalyst improves the crosslinking reaction. A series of seven PCAs was examined by thermal analytical (TA) and mass spectrometric (MS) techniques. The focus of this research was to discover if catalyst effects were measurable by TA and MS and to seek additional support for a proposed mechanism of cellulose/organic acid reactivity via acid anhydride formation. Thermal analyses consisted of differential scanning calorimetric (DSC) and thermogravimetric (TG) procedures. MS analyses, using the electron impact mode, were performed by direct probe sample insertion. Observed catalyst effects included shifts in peak positions to lower temperature/time, and were noticeable primarily in MS-reconstructed ion current chromatograms and DSC thermograms. Two TG parameters, the amount of residue produced and the rates of weight loss, offer ways to predict the effectiveness of a PCA with respect to smooth-drying character. The presence of the catalyst influenced both measurements in desirable directions. Finally, the catalyst did not alter TG water loss data that support the proposed mechanism of reaction with cellulose via an anhydride intermediate.     

Eco‐friendly durable press finishing of cellulose‐containing fabrics

To impart easy‐care properties to cellulose‐containing fabrics along with avoiding any harmful effects of formaldehyde on both the health and the environment, attempts have been made to use citric acid (CA) as an ester crosslinking agent along with different catalytic systems in the absence and presence of certain additives. Further, fixation conditions, type of crosslinking agent, as well as type of substrate have been studied. Results revealed that the enhancement in carboxyl content, performance properties, and the decrease in tear strength (TS) as well as in whiteness indices (WI) of the finished fabric samples were increased by increasing CA concentration up to 80 g/L and by raising thermofixation temperature from 140 up to 180°C for 90 s. Inclusion of triethanolamine hydrochloride (TEA. HCl), decreased the carboxyl content, TS, color strength K/S, as well as oily stain release rating (SRR) of the finished fabric samples along with an increase in bound nitrogen (%N), wrinkle recovery angle WRA, and an improvement in WI without affecting the durable press rating (DP). Within the range examined (0–30 g/L), increasing PEG‐600 concentration improved the wet resiliency, TS, as well as WI properties of the finished samples. Increasing DMDHEU ratio in the CA/DMDHEU crosslinking system gave rise to an increase in %N, WRA (dry and wet), DP, as well as in free CH₂O of finished fabrics, along with a slight improvement in WI values. On the other hand, the TS, carboxyl content, K/S, SRR values of the finished fabric samples were lower at a higher DMDHEU ratio. Increase in carboxyl content, %N, WRA (dry and wet), DP and SRR, as well as extent of post dyeing (K/S) of the treated fabric samples upon using different ester crosslinking agents followed the descending order: citric acid > pyromellitic dianhydride. The opposite holds true for the TS, and WI values. Among the esterifying catalysts used, and for a given set of finishing conditions, NaH₂PO₂ · H₂O proved to be the most effective one, and the following order of effectiveness may be drawn: NaH₂PO₂ · H₂O > K₂HPO₄ > Na₃–citrate > Na₂–tartrate. Inclusion of silicone softener in the finishing formulation brought about an improvement in softeness degree, WRA, %N, DP, TS as well as K/S values along with a decrease in carboxyl content, SRR, and WI values of the treated fabric samples, regardless of the used silicone softener.The performance properties of the finished fabric samples were determined by the type and nature of the substrate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2243–2253, 2002     

Two-step durable press treatment of cotton fabric

In this paper cotton fabrics were treated by two different methods with polycarboxylic acids (citric acid and butanetetracarboxylic acid) for durable press performance. The first was a two-step method in which the fabric was initially treated with citric acid and then treated by butanetetracarboxylic acid. The other was a mixed method in which the fabric was treated with a solution containing the two mixed polycarboxylic acids. Following the treatments, the wrinkle recovery angle, strength and strength retention of the resulting fabric were measured and compared.     

Thermal characteristics of unsaturated dicarboxylic acid durable press finishing systems

Thermoanalytical (TA) studies including differential scanning calorimetric (DSC) and thermogravimetric (TG) analyses were carried out to measure characteristics of dried mixtures based on two unsaturated polycarboxylic acids. Model 9% treatment (pad) solutions of maleic (M) and/or itaconic (I) acid, with and without potassium peroxydisulfate (K) as the free-radical initiator, were prepared with sodium hypophosphite (H) as the catalyst and vacuum oven-dried. DSC thermograms varied with each component; even the presence of a small amount of component K was evident. TG residue production and maximum rates of weight loss were the most useful thermal parameters. Residue/rate factors, used previously as predictors, were calculated. Previous studies indicated that high residues and low rates were indicators of combinations of reactants that resulted in good durable press treatments for fabrics. Residue/rate factors were used to rank the six mixtures that reflect actual fabric treatment combinations: MH, IH, MIH, and those same three with the initiator present. Rankings indicated that the presence of the initiator significantly increased the residue/rate factor for IHK and for MIHK. The presence of the initiator appears more beneficial to itaconic acid than to maleic acid. The rankings by the TA predictor agreed with textile properties measuring appearance and strength. © 1994 John Wiley & Sons, Inc.     

Water‐repellent finishing of cotton fabrics by ultraviolet curing

Cotton fabrics were water‐repellent‐finished by radical ultraviolet curing of silicone and urethane acrylates with different formulations. The fabrics were impregnated with undiluted resins and with toluene solutions or water emulsions. Moreover, cationic ultraviolet‐curable systems were also investigated, such as an epoxy‐functional polysiloxane and mixtures of an epoxy resin with hydroxyl‐containing silicone additives. The gel content and polymerization yield were considered for the ultraviolet‐curing process evaluation. Water‐resistance properties were determined in terms of the contact angle, wettability, moisture adsorption, and water vapor permeability measurements, whereas the morphology and surface composition of treated fabrics were examined with scanning electron microscopy and energy‐dispersive X‐ray analysis. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Flame‐retardant finishing of cotton fabrics using polyamino carboxylic acids and sodium hypophosphite

The purpose of this research was to use polyamino carboxylic acids (PACAs) and their combination with sodium hypophosphite (NaH₂PO₂) as a flame‐retardant finishing system for cotton fabrics. Flammability of cotton fabric was evaluated by 45° flammability test, differential scanning calorimetry and measuring the char yield. The combination of polyamino carboxylic acids and sodium hypophosphite as a phosphorus‐containing catalyst reduces the flammability of cotton. The pyrolysis properties and the results of char yield of the finished cotton show that with increasing amount of catalyst, the flame retardancy increases. Fastness against multiple laundering, whiteness and tensile strength of the cotton finished with PACAs/NaH₂PO₂ to multiple standard laundering have been studied, too. The flame retardancy effect has an acceptable washing fastness. Whiteness and tensile strength of the finished cotton do not change significantly. Copyright © 2012 John Wiley & Sons, Ltd.     

Cation exchange finishing of nonwoven polyester with polycarboxylic acids and cyclodextrins

We describe a chemical method for the finishing of polyester nonwoven fabrics that aimed to obtain ion exchange textiles. This approach was based on the use of polycarboxylic acids (PCA) and cyclodextrins as carbohydrate compounds and finishing agents, respectively. It was observed that the reaction between these reactants yielded a crosslinked polymer that was physically anchored onto the fibers. This polymer can be considered as a resin issued from the esterification between the COOH groups of the PCA with the OH groups of the carbohydrate. As the esterification reaction was not complete, many free carboxylic groups remained on the surface of the coating polymer. This feature offered the ion exchange properties to the textile support. In this article, we described the pad‐dry‐cure process and showed the influence of the curing parameters (time and temperature), the nature, and the concentration of the components and the pH of the impregnating bath. The grafting rate (in wt %) and the ion exchange capacity (IEC) were observed in parallel. First, it was observed that the best IEC capacity (that could reach 1 mmol/g) was obtained when an ideal compromise was applied between time and temperature of curing. We also evidenced that IEC depended on the nature and on the concentration of the PCA (chosen among citric acid, 1,2,3,4‐butanetetracarboxylic acid, and polyacrylic acid) and on the pH of the impregnating bath. Finally, it was observed that cyclodextrins were more appropriate than starch as finishing coreactants. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3730–3738, 2007     

Influence of pregrafting cotton fabrics on kinetics of DMEU finishing

Cotton fabrics were pregrafted with a mixture of N-methylolacrylamide and methacrylic acid at mixing molar ratio of 4/6. The influence of pregrafting on the kinetics of finishing with 1,3-dimethylolethylene urea was studied. The results shows that pregrafting can increase the rate constants. Values of E_a ΔH^*, ΔS^*, and ΔG^* suggest that the pregrafting of cotton fabric not only affects the reaction action state, but also is beneficial for the reaction between cellulose and the finishing agent. © 1996 John Wiley & Sons, Inc.     

Infrared spectroscopy studies of cyclic anhydrides as intermediates for ester crosslinking of cotton cellulose by polycarboxylic acids. IV. In situ free radical copolymerization of maleic acid and itaconic acid on cotton

Polycarboxylic acids have been used as crosslinking agents for cotton fabrics and paper to replace the traditional formaldehyde‐based reagents. Previously, we found that a polycarboxylic acid esterifies cotton cellulose through the formation of a five‐membered cyclic anhydride intermediate. Both maleic acid (MA) and itaconic acid (ITA) are extremely difficult to polymerize under conditions normally used for free radical polymerization. It has been reported in the literature that treatment of cotton fabric with a mixture of MA and ITA significantly improved wrinkle‐resistance of the fabric. In this research, we investigated the in situ copolymerization of MA and ITA on cotton fabric. Fourier transform‐infrared spectroscopy was used to study the anhydride carbonyl formed on the cotton fabric treated with the mixtures of MA and ITA. A redox titration technique also was applied to determine the quantity of alkene double bonds on the treated fabric. It was found that free radical copolymerization of MA and ITA does not occur on the fabric at elevated temperatures when potassium persulfate is present as an initiator. It does occur, however, when both potassium persulfate and sodium hypophosphite are present on the fabric. The in situ copolymerization on the cotton fabric probably is initiated by a reduction–oxidation system. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 327–336, 2000     

Ultraviolet resistant/antiwrinkle finishing of cotton fabrics by sol‐gel method

Nano titanium dioxide (TiO₂) sols were prepared by sol‐gel method with tetrabutyl orthotitanate (TBOT) as precursors, citric acid (CA) as inhibitors. Ultraviolet resistant capacity of finished cotton fabrics are greatly improved with good wrinkle‐resistance, whiteness and tensile strength as well. The optimum molar ratio for preparing nano‐TiO₂ sols in this study is n[C₂H₅OH] : n[H₂O] : n[CA] : n[HCl] : n[TOBT] = 20 : 6 : 1.2 : 0.025 : 1, at ambient temperature. Particle size distribution analysis of the sol reveals that the curve is right tailed with an average diameter of 72.8 nm. Factors affecting the performance of finished cotton fabrics by TiO₂ sols, such as concentration of sodium hypophosphite (SHP), triethanolamine (TEA) in finishing bath, curing temperatures and time lengths were investigated by orthogonal experiments. The optimum finishing results can be obtained with 3% SHP, 3% TEA, curing at 165°C for 3 min. Aggregated nano‐TiO₂ particles on surfaces of finished cotton fibers both washed and unwashed were investigated by high resolution cold field emission scanning electron microscope and energy dispersive X‐ray spectrometer. Esterification crosslinking between CA and cotton fibers were also demonstrated through infrared spectra. After a five‐time's wash, ultraviolet protection factor of finished cotton fabrics with nano‐TiO₂ sols is up to 117.42 and dry crease recovery angles increase by 30.2° with slightly improved whiteness, while the breaking strength decreases by 18.8%. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Infrared spectroscopic studies of thermotropic polyamides

Summary Poly (3,3, 5,5-tetraethyldiphenylmethane-1, 18-octadecanedi carboxamide) (poly(TEDPM-ODDA)) and poly(diphenylmethane-1, 18-octadecanedicarboxamide) (poly(DPM-ODDA)) are newly synthesized and found mesomorphic phase between 493 and 502 K for the former and no mesomorphic phase for the latter by use of DSC measurements and polarizing microscope observation. In the IR spectra of enantiotropic mesomorphic poly(TEDPM-ODDA), the stepwise high frequency shift of the hydrogen-bonded N-H stretching vibration in crystalline-mesomorphic and mesomorphic-isotropic liquid phase transition suggest formation of the mesomorphic state due to balancing interchain hydrogen bonding and other interchain forces. On the contrary, nonmesomorphic poly(DPM-ODDA) the N-H bands shifts to higher frequency at melting to isotropic liquid at a stretch.     

水性聚氨酯棉织物抗皱整理工艺探讨

针对纯棉织物急、缓弹回复角、断强保留率、白度和增重率几项指标,对合成的封闭型水性聚氨酯进行了抗皱整理工艺的研究。通过单因素和正交实验探讨了水性聚氨酯种类及用量、催化剂种类及用量、焙烘温度和时间对抗皱效果的影响,确定了水性聚氨酯抗皱整理最佳工艺条件。     

新型整理剂的合成

以环氧氯丙烷、八氟戊醇为原料,利用八氟戊氧基对环氧氯丙烷进行取代,合成了一种新型的拒水整理剂。配制了该拒水整理剂的水乳液,并应用于棉织物的拒水整理。研究了拒水整理剂的用量、焙烘温度对拒水整理效果的影响。优化了拒水整理工艺：拒水整理剂25％（对浴比的百分比,简称owb）,乳化剂25％（质量分数,简称owm）,160℃焙烘。结果表明,用于棉织物整理时防水效果可达70分。     

Effect of MAA/MAM pregrafting on DMEU finishing of cotton fabrics

Cotton fabrics were pregrafted with mixed monomer of methacrylic acid (MAA) and N-methylolacrylamide (MAM) before undergoing finishing with 1,3-dimethylolethylene urea. Experiments show that when the molar ratio of MAA and MAM is 4 : 6 the finished fabric has the maximum nitrogen content (N%) and crosslinking density. The pregrafting can improve the wet crease recovery angle and the moisture regain, can reduce the tensile strength retention, and has little effect on the dry crease recovery angle. In addition, at a pregrafting ratio of 4 : 6, the finished fabric has the highest crease recovery angle and moisture regain. © 1995 John Wiley & Sons, Inc.