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1 – 10 of 481N.N. Messiha, M.M. Abd El‐Malek and M.M.H. Ayoub
Three copolymer and three terpolymer systems involving tributyltin methacrylate, methyl methacrylate and acrylonitrile were prepared with variable tin content of 7, 15 and 22%…
Abstract
Three copolymer and three terpolymer systems involving tributyltin methacrylate, methyl methacrylate and acrylonitrile were prepared with variable tin content of 7, 15 and 22%. The structure of the organotin polymers was investigated by the elemental analysis of tin and nitrogen and by infrared spectroscopy. Long‐term leaching rate determinations of tin from the organotin polymer films were studied and were in the range of 0.033–0.045 ?g Sn/cm2/day. The antifouling performance of the prepared polymer varnishes was tested at Ismailia and at Alexandria. Tributyltin methacrylate‐methyl methacrylate copolymer with tin content of 22% exhibited the highest antifouling potential for more than 18 months.
Acrylic resins are formulated into protective coatings in several ways. Most important volumewise are waterborne formulations based either on pure acrylics or on acrylic‐vinyl…
Abstract
Acrylic resins are formulated into protective coatings in several ways. Most important volumewise are waterborne formulations based either on pure acrylics or on acrylic‐vinyl copolymers. Second most important are solvent‐based enamels and lacquers widely used for product finishes particularly in the automotive and appliance industries. An innovation of a decade or so ago is proving popular in this area, namely two component coatings based on hydroxyl‐containing acrylics and di‐ or polyisocyanates. These combine many of the good features of acrylics and urethanes and provide hard thermoset coatings. Yet they cure at temperatures as low as ambient.
A.A. Abd El‐Hakim, A.S. Badran and F.M. Helaly
Surface of aluminium oxide was modified using the adsorption of stearic acid molecules from benzene solution. The adsorption isotherm and the sedimentation properties of the…
Abstract
Surface of aluminium oxide was modified using the adsorption of stearic acid molecules from benzene solution. The adsorption isotherm and the sedimentation properties of the aluminium oxide in the organic medium were determined. Commercial unsaturated polyester was cured to a cross‐linked structure using styrene, methyl methacrylate and methyl acrylate monomers as cross‐linking agents, and small amounts of peroxidic initiator to initiate the curing process. Different composite materials of polyester‐modified surface aluminium oxide were prepared, and the physicomechanical properties of the prepared composites were measured for the products in the form of cast laminates and rods.
M.M. Abd‐El‐Malek, N.N. Messiha and M.M.H. Ayoub
To organotin polymer systems were prepared based on the reaction of tri‐n‐butyltin methacrylate with methyl methacrylate ad acrylonitrile. Tin content of the polymers was about…
Abstract
To organotin polymer systems were prepared based on the reaction of tri‐n‐butyltin methacrylate with methyl methacrylate ad acrylonitrile. Tin content of the polymers was about 22% and the physical properties of the organotin polymer films were investigated. The anti‐fouling potential of the prepared polymers was investigated as unpigmented and pigmented coatings at Alexandria and Port‐Said. Compositions containing vinyl copolymer as a co‐resin as well as cuprous oxide as a supporting toxin showed good antifouling performance for more than three years.
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
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.
Originality/value
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.
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D. Behera, H. Satapathy and A.K. Banthia
To evaluate the performance of a reactive diluent, nonylphenyl methacrylate (NPM) for toughness improvement of bisphenol‐a‐glycidyl dimethacrylate (BisGMA) and to optimise the…
Abstract
Purpose
To evaluate the performance of a reactive diluent, nonylphenyl methacrylate (NPM) for toughness improvement of bisphenol‐a‐glycidyl dimethacrylate (BisGMA) and to optimise the results of such a modification.
Design/methodology/approach
To achieve desirable rheological and physico‐mechanical properties of BisGMA/NPM network, various compositions were made by incorporating different concentrations of NPM. The effect of concentration on the impact and the adhesive strengths of the unmodified and modified BisGMA networks were characterised.
Findings
The modification of BisGMA resin using NPM showed significant enhancement of the impact and the adhesive strengths over the unmodified one. The modification caused a chemical linkage between NPM and BisGMA resin, which led not only to a phase separation but also to establishing the intrinsically strong chemical bonds across the NPM phase/resin matrix interphase, which was responsible for the improvement of the impact and adhesive strength. The optimum results were obtained at 10/h (parts per 100 parts of BisGMA resin) of modifier.
Research limitations/implications
The reactive diluent, used in the present context was synthesised from nonyl phenol, methacrylic acid and benzoyl chloride in methyl ethyl ketone using triethylamine as base.
Practical implications
The method of modification developed provides a simple and practical solution for improving the rheological and physico‐mechanical properties of BisGMA network.
Originality/value
The method developed is a novel one for enhancing the rheological and physico‐mechanical properties of BisGMA network diluted with NPM resin and may find numerous applications in surface coating and adhesive.
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Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer…
Abstract
Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer electrolytes. Molten palmitic acid will serve as a solvent in which to polymerise acrylic compounds, and benzyl butyrate has been examined as a solvent in which to polymerise benzyl methacrylate. Ethyl palmitate has been applied to aid the reduction of the carbon tetrachloride content of solutions of chlorinated polyisoprene, when this is removed from the polymer by steam or hot water.
Lijun Chen, Wen Li and Wei Jiang
The purpose of this paper was to prepare a fluorinated acrylate resin, which would be synthesised via solution polymerisation of fluorinated monomer, acrylate monomers and other…
Abstract
Purpose
The purpose of this paper was to prepare a fluorinated acrylate resin, which would be synthesised via solution polymerisation of fluorinated monomer, acrylate monomers and other functional monomers. Relevant characterisation and application studies were also carried out. Fluorinated polymers are expected to be adopted in specific coatings to afford outstanding advantages, such as high chemical and photochemical resistance, low surface tension and low refractive index. At present, fluorinated cathodic electrodeposition (CED) coatings are attracting the attention that they deserve and seldom reported.
Design/methodology/approach
Cationic fluorinated acrylic resin was successfully prepared by solution polymerisation of dodecafluoroheptyl methacrylate, butyl acrylate, methyl methacrylate, dimethylaminoethyl methacrylate and methacrylic acid initiated by 2,2,-azo-bis-iso-butyronitrile in a solvent of butyl cellosolve. The resultant resin was neutralised with acetic acid. The CED coatings are prepared when moderate amounts of blocked isocyanate and distilled water were added into the resultant resin.
Findings
The hydrophobicity of the film is improved when the fluorinated monomer is introduced to co-polymerise with other monomers. The optimum conditions of preparing the resin are as follows: the amount of azodiisobutyronitrile is controlled with the range of 3.0 and 4.0 per cent; the amine value of the resin is 70 mg KOH/g; the hydroxyl value of resin and mole ratio of hydroxyl to isocyanate is 60 mg KOH/g and 1.0/1.0, respectively; the degree of neutralisation of the resin is within the range of 35 and 40 per cent.
Practical implications
The cationic fluorinated acrylic resin can be used to be the binder of CED coatings, which can be applied to electrodeposition finishing for high demand of exterior decorative and weather resistance, such as hardware, accessories, office furniture and so on.
Originality/value
The cationic fluorinated acrylic resin was successfully prepared by solution polymerisation. The hydrophobicity of the film is improved.
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Mostafa Abdel-Hamied, Ahmed A.M. Abdelhafez and Gomaa Abdel-Maksoud
This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.
Abstract
Purpose
This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.
Design/methodology/approach
For each material, chemical structure, chemical composition, molecular formula, solubility, advantages, disadvantages and its role in treatment process are presented.
Findings
This study concluded that carboxy methyl cellulose, hydroxy propyl cellulose, methyl cellulose, cellulose acetate, nanocrystalline cellulose, funori, sturgeon glue, poly vinyl alcohol, chitosan, chitosan nanoparticles (NPs), gelatin, aquazol, paraloid B72 and hydroxyapatite NPs were the most common and important materials used for the consolidation of illuminated paper manuscripts. For the leather bindings, hydroxy propyl cellulose, polyethylene glycol, oligomeric melamine-formaldehyde resin, acrylic wax SC6000, pliantex, paraloid B67 and B72, silicone oil and collagen NPs are the most consolidants used.
Originality/value
Illuminated paper manuscripts with leather binding are considered one of the most important objects in libraries, museums and storehouses. The uncontrolled conditions and other deterioration factors inside the libraries and storehouses lead to degradation of these artifacts. The brittleness, fragility and weakness are considered the most common deterioration aspects of illuminated paper manuscripts and leather binding. Therefore, the consolidation process became vital and important to solve this problem. This study presents the main materials used for consolidation process of illuminated paper manuscripts and leather bindings.
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The purpose of this paper is to modify the surface property of polyacrylate latex films using only small amounts of fluorinated acrylate and to optimise the results of such a…
Abstract
Purpose
The purpose of this paper is to modify the surface property of polyacrylate latex films using only small amounts of fluorinated acrylate and to optimise the results of such a modification.
Design/methodology/approach
The core‐shell particles with polyacrylate rich in core and containing fluorinated polymer rich in shell are prepared by a two‐stage semi‐continuous emulsion polymerisation under kinetically controlled conditions. The surface properties of the latex films produced from the core‐shell particles are investigated by optical goniometer measurement as well as contact angle method.
Findings
The latex films produced from the core‐shell particles exhibited surface energy of around 10 mN/m. The angle resolved X‐ray photoelectron spectrum measurements showed an increased average fluorine concentration in a surface layer thickness of a few nanometres, when compared to the fluorine concentration in the bulk.
Research limitations/implications
Methyl methacrylate, butyl acrylate and N‐methylol acrylamide monomers are used as co‐monomer to form the shell with fluoroalkyl methacrylate. By preparing core‐shell emulsion with a fluoropolymer in the shell phase, the surface property of polyacrylate latex films is efficiently modified by using only small amounts of fluorinated acrylate monomer.
Practical implications
The method developed provided a simple and practical solution to improving the surface property of polyacrylate latex films.
Originality/value
The method for enhancing surface property of polyacrylate latex films is novel and can find numerous applications in surface coating.
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