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To explore the effect of acrylic acid polymerization and NaOH treatment of nylon‐6 on hemoglobin washability.

The nylon‐6 was chemically grafted with acrylic acid and treated with NaOH for the purpose to improve the washability of hemoglobin as a blood protein soil. The structural change before and after graft polymerization was analyzed by X‐ray photoelectron spectroscopy and scanning electron microscopy. The moisture regain, the contact angle, and the washability were each measured.

Graft polymerization and NaOH treatment of nylon‐6 changed the surface energy and structure of nylon‐6 causing the washability of hemoglobin to improve. Compared to ungrafted nylon‐6, the hydrophilic properties were increased remarkable by graft polymerization and NaOH treatment, which reulted in the improvement of washability.

Hemoglobin is one of the most difficult soils to remove from the fabric. The paper might be of interest to those who would consider purchasing fabrics that are good at both hydrophilic properties and washability.

The study on washability of hemoglobin as a blood protein soil for grafted fabric has not been reported so far. The results of this research may be used in a basic research for the development of new process which is capable of improving of hemoglobin washability.

The purpose of this study is to undertake surface graft copolymerization of viscose fabric via altering its fibrous properties by using acrylic acid (AA) as a carboxyl-containing monomer and peroxydisulfate (PDS) in presence of ferrous sulfate as a novel redox pair for initiating grafting. The latter process acted as an energy-saving process with respect to the reduction in polymerization temperature and maximizing the graft yield %, in addition to rendering the grafted viscose fabrics dye-able with cationic dye (crystal violet), which has frequently no direct affinity to fix on fabric.

To make graft copolymerization more efficient and economic, the optimum conditions for graft copolymerization were established. The graft yield % was determined as a function of initiator, catalyst and monomer concentrations and the material to liquor ratio, in addition to polymerization time and temperatures. Metrological characterizations via Fourier transform infrared spectroscopy and scanning electron microscopy of topographic morphological surface change have also been established in comparison with the ungrafted samples.

The maximum graft yield of 70.6% is obtained at the following optimum conditions: monomer (150 % based on the weight of fabric), PDS (50 m mole), ferrous sulfate (80 m mole) and sulfuric acid (30 m mole) at 40° C for 1.5 h using a liquor ratio of 30. Remarkably, grafting with AA enabled a multifold upsurge in color strength, with improvements in the fastness properties of cationically dyed grafted viscose fabric measured on the blue scale in comparison with untreated viscose fabric.

The novelty addressed here is undertaken with studying the effect of altering the extent of grafting of poly (AA)-viscose graft copolymers expressed as graft yield % in addition to carboxyl contents on cationic dyeing of viscose fabric for the first time in the literature. Moreover, rendering the viscose fabrics after grafting is dye-able with cationic dye with high brilliance of shades, which has regularly no direct affinity to fix on this type of fabrics.

The purpose of this paper is to synthesise carboxymethylcellulose and methyl methacrylate graft copolymers (CMC‐g‐PMMA), which is used as an effective additive, for reinforcing the rice‐hull‐cement composite.

Various CMC‐g‐PMMA copolymers were synthesised at different reaction temperatures, pH values of reaction solution and the dosages of monomer and initiator (potassium persulphate). The copolymers were characterised by Fourier transforms infrared (FT‐IR) spectra, thermal analysis (thermogravimetric and differential scanning calorimeter), X‐ray diffractometry (XRD) and scanning electron microscopy.

An optimal CMC‐g‐PMMA copolymer is obtained. For synthesis of the CMC‐g‐PMMA, the optimal reaction temperature is 80°C and pH value is 9. FT‐IR test of CMC‐g‐PMMA confirmed the existence of a chemical link between carboxymethylcellulose (CMC) and methyl methacrylate (MMA). The content of initiator has little effect on the reaction for synthesising the graft copolymer. Thermal analysis indicates the occurrence of graft reaction in CMC and MMA. XRD test proved that the chains of the graft copolymer can enlarge the proportion of the amorphous regions of CMC. Adding MMA has damage effect on the crystallisation.

Since the results of this paper are obtained from the laboratory experiments, further research should be conducted for evaluating the performances of this copolymer in practical application.

The mechanical test of the rice‐hull‐cement composite proved that CMC‐g‐PMMA is an effective additive for reinforcing the rice‐hull‐cement composite. The synthesis of CMC‐g‐PMMA provides a new alternative for modifying cellulose derivatives.

The CMC‐g‐PMMA obtained in this paper is a new kind of effective agent. It can reinforce the rice‐hull‐cement composite and expands the application of the composite in building industries.

Plasma polymerization is a very promising technique to produce functional textile materials for any textile end uses as well as for high performance clothing. It can be possible to obtain highly cross‐linked, pinhole free and very thin polymer films up to 1 μm thickness with unique physical and chemical properties. These films can be used as very effective barriers. The purpose of this paper is to investigate the influences of plasma polymerization of hexamethyldisilane (HMDS) and hexamethyldisiloxane (HMDSO) on the surface properties of cotton and polyamide fabrics.

The methodology is based on the surface modification of the cotton and polyamide fabrics by plasma polymerization of HMDS and HMDSO. The fabrics are modified by low pressure low temperature RF (radio frequency −13.56 MHz) plasma polymerization system under different power and time conditions. The changes in surface structure and morphology of the fabrics are investigated by Fourier transform infrared spectroscopy‐attenuated total reflectance (FTIR‐ATR) analysis and atomic force microscopy (AFM).

Water repellency of polyamide fabrics is strongly enhanced after plasma polymerization of both HMDS and HMDSO monomers. In addition to this, the treatments are found to slow down the vertical flame spread in cotton fabrics.

Increased water repellency and decreased vertical flame spread are achieved using plasma polymerization technique in a very short time with very little amount of chemical and without water and auxiliary agent.

The purpose is to focus on improving the water or metal ion uptake of modified cellulose.

Grafting copolymerisation of hydrophilic monomers such as acrylamide or hydrophobic monomers as acrylonitrile onto cotton linters was performed.

The grafting process has two advantages. The first is to replace the hydroxyl group of C₆ of the glucose units in the substrate by carboxyl group that attract the metal ions from the solution. The second is to decrease the number of the hydroxyl groups in the cotton linters so that the hydrogen bonding between the cotton linters strands decreases and so the crystallinity index of substrate decreases by introduction of this hydrophilic group so it becomes more chemically active.

Partial substitution of hydroxyl groups of cellulose by more hydrophilic ones via grafting reaction followed by alkaline hydrolysis was performed. The effects of different conditions such as temperature, time, initiator concentration, monomer concentration and kind of substrate were studied. The polymerisation per cent, grafting per cent, the grafting efficiency and the nitrogen per cent of the grafted samples were determined. The molecular structures of cotton linters, grafted cotton linters with acrylamide and its hydrolysis product were studied using infrared spectroscopy, which indicates the fixation of the monomers on the cotton linters. Sodium binding capacity and the metal ion uptake of some metal ions by the product were determined.

The water or metal ion uptake of the modified cellulose was improved.

Carbamoylethyl starch (CrES) and cyanoethyl starch (CES) were prepared by making use of the concept of the dry process under conditions which were developed to form the bases of environmentally sound (clean) technology. The obtained CrES and CES were saponified using alcoholic NaOH solution. The CrES and CES along with their saponified products were further modified by subjecting them to graft polymerization with Aam/AN mixture. Saponification of the so‐obtained grafted substances was also carried out. Presents the findings of these investigations which are explained in terms of structural changes in the starch, the ‐CN and CONH₂ groups, the Aam/AN polymeric graft and the site of attachment of the latter on the modified starch.

This study aims to prepare an imprinted composite membrane with grafted temperature-sensitive blocks for the efficient adsorption and separation of rhenium(Re) from aqueous solutions.

PVDF resin membrane was used as the substrate, dopamine and chitosan (CS) were used to modify the membrane surface and temperature-sensitive block PDEA was grafted on the membrane surface. Then acrylic acid (AA) and N-methylol acrylamide (N-MAM) were used as the functional monomers, ethyleneglycol dimethacrylate (EGDMA) as the cross-linker and ascorbic acid-hydrogen peroxide (Vc-H₂O₂) as the initiator to obtain the temperature-sensitive ReO4⁻ imprinted composite membranes.

The effect of the preparation process on the performance of CS–Re–TIICM was investigated in detail, and the optimal preparation conditions were as follows: the molar ratios of AA–NH₄ReO₄, N-MAM and EGDMA were 0.13, 0.60 and 1.00, respectively. The optimal temperature and time of the reaction were 40 °C and 24 h. The maximum adsorption capacity of CS–Re–TIICM prepared under optimal conditions was 0.1071 mmol/g, and the separation was 3.90 when MnO4⁻ was used as the interfering ion. The quasi first-order kinetics model and Langmuir model were more suitable to describe the adsorption process.

With the increasing demand for Re, the recovery of Re from Re-containing secondary resources becomes important. This study demonstrated a new material that could be separated and recovered Re in a complex environment, which could effectively alleviate the conflict between the supply and demand of Re.

This contribution provided a new material for the selective separation and purification of ReO4⁻, and the adsorption capacity and separation of CS–Re–TIICM were increased with 1.673 times and 1.219 time compared with other Re adsorbents, respectively. In addition, when it was used for the purification of NH₄ReO₄ crude, the purity was increased from 91.950% to 99.999%.

Chitin was extracted from locally collected shrimp shells. Chitosan was produced by alkali deacetylation of chitin. Poly(DEAEMA)‐chitosan‐graft‐copolymer, poly(COOH)‐chitosan‐graft‐copolymer, poly(V‐OH)‐chitosan‐graft‐copolymer, and carboxymethyl‐chitosan were prepared. The extent of the preparation reactions was expressed as nitrogen content, carboxylic content and graft yield. The ability of the prepared compounds to adsorb heavy metals ions and some dyestuffs was studied. The prepared compounds were also tested for corrosion protection when applied in some organic coatings for steel panels. Promising results to use the prepared compounds for corrosion protection and wastewater treatment from heavy metal ions and dyestuffs were obtained.

This paper aims to study previously prepared and fully characterized chitosan nanoparticles (CNPs) as a starting substrate and microwave initiation technique for grafting acrylic acid (AA). This was done to see the influence of both CNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability, biocompatibility and reactivity and microwave initiation technique with respect to reduction in organic solvents, toxic chemical initiator and exposer time on exploiting the graft yield % and enhancing water solubility and antibacterial properties.

For evaluating the best accurate standard metrological method for calculating the graft yield %, the grafting parameters were stated in terms of graft yield percent and measured gravimetrically (based on dry weight method) and titrimetrically (based on carboxyl content). Microwave power, AA and CNPs concentrations and reaction duration were shown to be the most important parameters influencing the grafting process.

The optimum reaction conditions were obtained when CNPs 1.5 g, AA 150 bows, microwave irradiation power 500 W and reaction duration 120 s were used. Various analytical methods were used to characterize CNPs and poly(AA)–CNPs graft copolymers. According to the findings, Fourier transform infrared spectroscopy examination determines the attachment of carboxyl groups to CNPs chains. The thermogravimetric analysis revealed that the copolymers were more thermally stable than CNPs counterparts. Furthermore, the resulting copolymers were shown to have greater water solubility biodegradability resistance and antibacterial properties than CNPs counterpart. Finally, a preliminary mechanism demonstrating all occasions that occur during the polymerization reaction has been proposed.

The advancement addressed here is undertaken using previously prepared and fully characterized CNPs as a green bio-nanocompatible polymer and microwave initiation technique as green and efficient tool with respect to reduction in organic solvents toxic chemical initiator and exposer time for grafting AA.

In this study, fabrication of polymer and cotton fabric exhibiting stimuli-responsive wetting and water vapor permeability features together with antibacterial activity was aimed.

Temperature and pH-responsive poly(N-isopropyl acrylamide-graft-chitosan) (PNIPAM-g-CS) copolymer were produced via the free radical addition polymerization method and fixed to the cotton fabric using butane tetracarboxylic acid (BTCA) cross-linker by double-bath impregnation method. The chemical structure of the graft copolymer was characterized by Fourier-transform infrared spectroscopy (FT-IR) spectroscopy and H-Nuclear magnetic resonance (1H NMR) analyses. Thermo-responsive behavior of the fabric was investigated by wetting time and water uptake tests, contact angle measurement and surface energy calculation. Additionally, antibacterial activity of the fabric treated with copolymer was studied against S. aureus bacterium.

PNIPAM-g-CS graft copolymer was synthesized successfully, which had lower critical solution temperature (LCST) value of 32 °C and exhibited thermo-responsive property. The treated fabrics exhibited hydrophilic character at temperatures below the LCST and hydrophobic character at temperatures above the LCST. It was found that polymer-coated fabric could have regulated the water vapor permeability by the change in its pore size and hydrophilicity depending on the temperature. Additionally, treated fabric displayed a pH-responsive water absorption behavior and strong antibacterial activity against S.aureus bacterium.

In the study, it has been shown that the cotton fabrics can be fabricated which have antibacterial activity and capable of pH and temperature responsive smart moisture/water management by application of copolymer. It is thought that the fabric structures developed in the study will be promising in the production of medical textile structures where antibacterial activity and thermophysiological comfort are important.