F.A. Abdel‐Mohdy, A. Waly, A. Higazy and A. Hebeish
Perfluoroheptyl methacrylate was copolymerized with acrylamide using different ratios of these monomers. The copolymers so obtained were methylolated with formaldehyde. The…
Abstract
Perfluoroheptyl methacrylate was copolymerized with acrylamide using different ratios of these monomers. The copolymers so obtained were methylolated with formaldehyde. The methylolated copolymers were used as multi‐purpose finishing agents for cotton. They impart oil and water repellence. Attachment of the methylolated copolymer to cotton is presumed to involve chemical bonds via reaction of the methylol groups of the copolymer and the hydroxy groups of cotton cellulose. This was evidenced by the wash‐fastness properties; no significant differences were noted in the oil/water repellence of cotton fabric treated with the copolymers in question.
The behaviour of chemically modified cellulose towards dyeing is an interesting subject. Cellulose undergoes substantial changes in its chemical and physical properties by…
Abstract
The behaviour of chemically modified cellulose towards dyeing is an interesting subject. Cellulose undergoes substantial changes in its chemical and physical properties by chemical modification. Some investigations were carried out to study the effect of these changes on dyeing and dyeing properties of cellulose. Previous reports have disclosed that the dyeability of chemically modified cellulose differs significantly when compared with the unmodified cellulose. Among the modified cellulose studied were partially acetylated cellulose, cyanoethylated cellulose, carboxymethylated cellulose, cellulose tiaocarbonate and cellulose copolymerized with various vinyl monomers.
A. Hebeish, A. Waly, F.A. Abdel‐Mohdy and A.S. Aly
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…
Abstract
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.
S.A. Abdel‐Hafiz, F.F. El‐Sisi, M. Helmy and A. Hebeish
Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting agent. The…
Abstract
Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting agent. The samples were then washed and treated using solutions containing methacrylic acid, wetting agent and acid or basic dye along with citric acid of different concentrations at different temperatures for different times. The critical properties of the fabric such as graft yield (expressed as carboxyl content m.eq/100g cellulose), colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend on the concentrations of KMnO4, citric acid and methacrylic acid as well as duration of the treatment. Based on the results obtained, treating formulations consisting of KMnO4 (0.1g/l), citric acid (0.1g/l), methacrylic acid (50 per cent), dye (1 per cent) and wetting agent (2g/l) was considered appropriate for concurrent grafting and dyeing of the said fabrics provided that the treatment was carried out at 90°C for 60 minutes.
Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone, brick, metal…
Abstract
Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone, brick, metal and plastic are all derived from exhaustible mineral sources.
Starch/carboxymethylstarch‐poly (acrylonitrile, acrylamide, vinyl acetate) composites have been successfully prepared through polymerization of acrylonitrile, acrylamide or vinyl…
Abstract
Starch/carboxymethylstarch‐poly (acrylonitrile, acrylamide, vinyl acetate) composites have been successfully prepared through polymerization of acrylonitrile, acrylamide or vinyl acetate with starch or carboxymethyl starch (CMS) using ceric‐ion type CeIV catalyst. The obtained composites were saponified using alcoholic KOH solution. Regardless of the composite used, results obtained led to the following: (a) enhancement of solubility percent as compared with starch and CMS; (b) the size removal reaches 100 percent for a given set of desizing condition used; (c) the tensile strength and elongation at break increase with sizing, while crease recovery decreases; (d) sizing treatment in the presence of the prepared composites gives positive influence on the abrasion resistance; and (e) incorporation of CMS in composite form in the sizing formulation exerts a considerable positive influence on the performance properties of the sized fabrics as compared with other sizing agents under investigation.
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A. Higazy, M.H. El‐Rafie, M.A. Ramadan and A. Hebeish
Poly (acrylic) starch composites were prepared by polymerizing acrylic acid, acrylamide alone or in admixtures with maize starch using KMnO4/citric acid as redox initiation. The…
Abstract
Poly (acrylic) starch composites were prepared by polymerizing acrylic acid, acrylamide alone or in admixtures with maize starch using KMnO4/citric acid as redox initiation. The cooked composite pastes were used as partial substituent of kerosene oil emulsion in the pigment printing pastes for cotton fabric. Printing was carried out under a variety of conditions including neutralization of the free carboxylic groups of the polyacrylic acid component in the composite or AA/Aam mixtures, composite concentration, and the type of pigment dyes. The effect of storage on the efficiency of the printing paste was also examined. The printed samples were assessed for colour strength (K/S) overall fastness properties. Results obtained indicate that:
Sanaa M. El‐Sawy, Yosreya M. Abu‐Ayana and Fikry A. Abdel‐Mohdy
Chitin was extracted from locally collected shrimp shells. Chitosan was produced by alkali deacetylation of chitin. Poly(DEAEMA)‐chitosan‐graft‐copolymer…
Abstract
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.
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Khaled Mostafa, Mohamed Ramadan and Azza El-Sanabary
This study aims to address a comprehensive and integrated investigations pertaining to the preparation of AgNPs with well-defined nano-sized scale using the aforementioned poly…
Abstract
Purpose
This study aims to address a comprehensive and integrated investigations pertaining to the preparation of AgNPs with well-defined nano-sized scale using the aforementioned poly (meth acrylic acid [MAA])–chitosan graft copolymer, which is cheap, nontoxic, biodegradable and biocompatible agent as a substitute for the traditionally used toxic reducing agents.
Design/methodology/approach
AgNPs are prepared under a range of conditions, containing silver nitrate and poly (MAA)–chitosan graft copolymer concentrations, time, temperature and pH of the preparation medium. To classify AgNPs obtained under the various conditions, ultraviolet–visible spectroscopy spectra and transmission electron microscopy images are used for characterization of AgNPs instrumentally in addition to the visual color change throughout the work. The work was further extended to study the application of the so prepared AgNPs on cotton fabric to see their suitability as antibacterial agent as well as their durability after certain washing cycles.
Findings
According to the current investigation, the optimal conditions for AgNPs formation of nearly 3–15 nm in size are 5 g/l, poly (MAA)–chitosan graft copolymer and 300 ppm AgNO3 in addition to carrying out the reaction at 60°C for 30 min at pH 12. Besides, the application of the so prepared AgNPs on cotton fabric displayed a substantial reduction in antibacterial efficiency against gram-positive and gram-negative bacteria estimated even after 10 washing cycles in comparison with untreated one.
Originality/value
To the best of the authors’ information, no comprehensive study of the synthesis of AgNPs using poly (MAA)–chitosan graft copolymer with a graft yield of 48% has been identified in the literature.
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A. Hebeish, M. H. El-Rafie, M. A. Ramadan and M. E. El-Naggar
Hydroxypropyl starch (HPS) is synthesized by using maize starch and different concentrations of both propylene oxide )PO) and sodium hydroxide (NaOH) with the intent to obtain HPS…
Abstract
Hydroxypropyl starch (HPS) is synthesized by using maize starch and different concentrations of both propylene oxide )PO) and sodium hydroxide (NaOH) with the intent to obtain HPS products which can better serve as a reducing and stabilizing agent during the preparation of silver nanoparticles. Such a preparation is carried out under a variety of conditions which include: pH, temperature, duration of the reaction medium, molar substitution (MS) of HPS, and concentration of both HPS and silver nitrate (AgNO3). The yield of silver nanoparticle colloids is monitored via color and ultraviolet (UV) visible spectral analyses whereas their evaluation is performed by making use of a transmission electron microscopy (TEM) to determine size and size distribution. The results obtained conclude that the optimum conditions for preparation of silver nanoparticle colloids with excellent size and size distribution which range from 6-8 nm could be produced by using 0.9 gm of HPS (MS = .84), 0.425 gm of AgNO3, a pH of 12, and temperature of 70°C for 15 minutes. Furthermore, the silver nanoparticle colloid solution prepared under these conditions is stable and remains without aggregation for more than six months. Thus preparation of a well stabilized silver nanoparticle solution with a concentration of 1608 ppm and a diameter of 9-18 nm can be achieved. A silver nanoparticle solution with these unique characteristics may be suitable for industrial applications.