Search results
1 – 10 of over 1000This paper aims to synthesise a novel crosslinker (crosslinker triethylthiosulphate (TETS)) which contains three Bunte groups in its molecule. The crosslinker is able to react…
Abstract
Purpose
This paper aims to synthesise a novel crosslinker (crosslinker triethylthiosulphate (TETS)) which contains three Bunte groups in its molecule. The crosslinker is able to react with the hydroxyl groups in cellulosic fibres and the amino group in protein fibres so that it may find applications in many fields.
Design/methodology/approach
Crosslinker TETS was synthesised under constant reflux. Capillary electrophoresis analysis and Raman analysis were used to follow the synthetic reaction and characterise the product. The crosslinking between TETS and cellulose could be confirmed by infrared analysis and elemental analysis.
Findings
Crosslinker TETS 2,2′,2″‐nitrilo‐TETS was synthesised with a yield of 71.3 per cent. The synthetic reaction follows the mechanism of first, aziridine‐forming and then cyclo‐opening by nucleophiles. A new low‐cost purifying method using ethanol at different temperatures with good yield was proposed.
Research limitations/implications
Practical applications of crosslinker TETS could be studied further.
Practical implications
Crosslinker TETS may find its use in durable‐press finish of cotton fabric, cellulosic fibre modifying to improve dyeing properties and increase fixation of reactive dyes, wet strength improvement of Kraft paper, anti‐fibrillating finish of Lyocell fibre, etc.
Originality/value
A novel polyfunctional crosslinker which belongs to a new Bunte salt was created. The structure, the synthetic reaction, the separation method and the crosslinking reaction of crosslinker TETS have not been reported before.
Details
Keywords
Andrzej Krysztafkiewicz, Teofil Jesionowski and Jacek Walkowiak
The technique is presented for obtaining green pigments in the reaction of precipitation from sodium metasilicate solution and from chromium (III) salts. Sulphates and chlorides…
Abstract
The technique is presented for obtaining green pigments in the reaction of precipitation from sodium metasilicate solution and from chromium (III) salts. Sulphates and chlorides of chromium (III) as well as chromium sulphates from the tanning industry refuses were applied. The studies were directed to obtain pigments of the following composition: xCr2O3 ySiO2 zH2O. Basic conditions of precipitation process, filtration and drying of silicate pigments were established. Moreover, principal physicochemical parameters of the precipitated pigments were evaluated as well as the size and morphology of pigment particles being estimated by electron microscopy. The performed physicochemical studies aimed also at determining suitability of the pigments as fillers and carriers in oil paints.
Details
Keywords
Studies the various contemporary standard brick products that areavailable and examines in detail their inherent properties andclassifications which ensures that British bricks…
Abstract
Studies the various contemporary standard brick products that are available and examines in detail their inherent properties and classifications which ensures that British bricks conform to the requirements of British Standards Specifications. These properties are significant and the engineer and architect must give them due consideration, for it is their responsibility to ensure they specify correctly for particular applications, and in so doing they should bear in mind that all bricks are not necessarily appropriate for all applications. This information will help professionals to make well‐considered judgements on brick selection and application.
Details
Keywords
Provides basic steps and general guidelines for the correct use ofplaster and render. Includes suggestions of several preparationsavailable to aid this process.
Abstract
Provides basic steps and general guidelines for the correct use of plaster and render. Includes suggestions of several preparations available to aid this process.
Details
Keywords
Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of…
Abstract
Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of plastics and metals such as zirconium, titanium and tantalum. Plastics are finding extensive use as lining materials for chemical plant operating at moderate temperatures, but the poor thermal conductivity of most plastics makes them unsuitable for the transfer of heat. The recently developed metals and their alloys are extremely expensive to produce and fabricate and, so far, their use has been confined to certain specialised applications, although full‐scale production of zirconium is being carried out in America, mainly because of the low capacity of the metal for absorbing thermal neutrons. At the moment, however, these metals, because of their high cost, cannot compete commercially on a large scale with the older well‐established corrosion‐resisting alloys such as the high‐silicon iron alloys. The excellent corrosion resistance of the high‐silicon iron alloys, even at high temperatures, and their high thermal conductivity have established them as almost standard alloys for acid concentration and cooling plant construction. The following article outlines their composition and properties.
OXYGEN, HUMIDITY, air pollutants, and dust are the chief causes of atmospheric corrosion in industrial plant and equipment. Oxygen, of course, is always present in air at a…
Abstract
OXYGEN, HUMIDITY, air pollutants, and dust are the chief causes of atmospheric corrosion in industrial plant and equipment. Oxygen, of course, is always present in air at a constant concentration. The chief variables which affect the plant's atmospheric corrosion loss are, therefore, humidity, electrolytes in the air, and dust. These components may be corrosive by themselves or many promote the corrosive effect of oxygen.
A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and…
Abstract
A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and sulphur containing materials, etc.
Kumaran Coopamootoo and Reshma Rughooputh
The cementitious/chemical properties of the untreated CFA are dependent on the coal composition and previous burning conditions. The purpose of this paper is to investigate…
Abstract
Purpose
The cementitious/chemical properties of the untreated CFA are dependent on the coal composition and previous burning conditions. The purpose of this paper is to investigate whether untreated CFA can efficiently reduce cement replacement and does not require further combustion treatment to be a viable cement replacement.
Design/methodology/approach
Two types of mixes: Type I concrete and PCFA (Type I and 30 per cent untreated CFA) concrete were batched and subjected to compressive strength tests and cyclic exposures of 5 per cent sodium sulphate (Na2SO4) and 5 per cent magnesium sulphate (MgSO4), respectively.
Findings
PCFA mix was 41.1 and 35.21 per cent lower in strength compared to Type I at 28 and 56 days correspondingly. Continuous-sulphate-exposure resulted in slow but continued strength development for both mixes. However, the strengths of PCFA cubes exposed to cyclic sulphate and sulphate/magnesium salts continued to increase at a lower rate from their corresponding 28-day strength (rate of 18.7 per cent and strength 27.30 MPa in Na2SO4 and rate of 10.0 per cent and strength 25.30 MPa in MgSO4) while Type I specimens subjected to the same exposure conditions experienced drastic reductions in strength (rate of −15.0 per cent and strength 33.21 MPa in Na2SO4 and rate of −23.4 per cent and strength 29.94 MPa in MgSO4).
Research limitations/implications
Results justify the need for additional tests essentially: at different percentage replacement of untreated CFA, fineness of materials, chloride environment and longer exposures, to address the cementitious properties of untreated CFA as cement replacement.
Originality/value
Treatment methods for fly ashes require undoubtedly additional resources, energy input and cost. This paper paves the way to define whether untreated CFA can be used as cement replacement in concrete.
Details
Keywords
Although cure of paint coatings by radiation is no new phenomenon, there is considerable increased interest in development of industrial processes using radiation curing for a…
Abstract
Although cure of paint coatings by radiation is no new phenomenon, there is considerable increased interest in development of industrial processes using radiation curing for a variety of reasons. Before studying the developments in detail, it is worth noting that radiated energy can basically be divided into two categories. In the first category we have ionising radiation which for our purposes includes electromagnetic radiation of wave lengths less than visible light and also accelerated electrons. In the second category is radiation, which is essentially thermal in its effect ranging from infra red through to microwave and radio frequency. The use of these longer wave length radiations, whose effect is essentially thermal, will not be discussed in detail since all coatings which can be cured in normal high temperature ovens are basically capable of cure with such methods. It is worth noting however, that improvement in the design of infra red lamps with peak radiation in the near infra red at around 1200 nanometers has led to speed up in infra red curing which has been particularly useful in cure of alkyd‐amino finishes on heat sensitive substrates such as wood. There is also developing interest in high frequency long wave length radiation, particularly in the area usually referred to as microwave. Here we have penetrative radiation which produces heat effects by what is sometimes referred to as molecular friction. The conversion of the microwave energy into heat depends on the loss factor of the material in question and so the process is most efficient with polar materials such as water. The most likely use of microwave heating is with water based coatings on substrates which will not themselves heat up rapidly, such as non‐polar plastic films.
Yuting Lu, Wanwan Fu, hao Ren, Shifang Wu, Jiesheng Liu and Hao Peng
The purpose of this paper is to develop a high-performance composite emulsion cement waterproof coating. The coating has excellent durability and is effective in protecting cement…
Abstract
Purpose
The purpose of this paper is to develop a high-performance composite emulsion cement waterproof coating. The coating has excellent durability and is effective in protecting cement mortar substrates from harmful ions.
Design/methodology/approach
The polymer cement waterproof coatings with different emulsion compounding ratios were tested for mechanical properties and water resistance after alkali immersion, water immersion, thermal aging and UV aging, and the coatings were analyzed by infrared spectroscopy after aging to evaluate its durability. Meanwhile, the coating that presents favorable durability was applied to cement mortar test blocks. The protective effect of the coating on the test blocks was tested by immersion method, and X-ray diffraction analysis was performed on the eroded test blocks.
Findings
The coating with neoprene latex/acrylate latex weight ratio of 90/10 presents favorable durability and has superior overall performance. Besides, when it is applied to cement mortar blocks, the coatings effectively reduced the erosive effect of harmful ions on cement mortar blocks, resulting in much lower mass change ratios and less internal structural damage of the blocks significantly.
Originality/value
The obtained coating will be of great application potential for use in building waterproofing construction. Moreover, the coating can practically prevent chloride ions and sulfate ions from penetrating cement-based materials.
Details