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Jetting‐based additive manufacturing processes are gaining attention due to their high speed of operation, accuracy and resolution. Support material plays an important role in the additive manufacturing of parts by using processes that utilise jetting (inkjet) technology. This research aims to present novel support material compositions consisting of methylcellulose (MC) and propylene glycol or butylene glycol. These compositions form gels which are easy to remove and provide the advantage of reusability.

MC was mixed in propylene glycol or butylene glycol in different concentrations and examined for gel formation on heating and subsequent cooling. The viscosity and surface tension of these compositions were measured at temperatures suitable for jetting. Gel strength was characterised using texture analysis.

The viscosity and surface tension values at elevated temperatures (i.e. 800°C) show the suitability of these compositions for jetting‐based additive manufacturing processes. Due to their softness, these gels can be removed easily and their low melting points (i.e. near 500°C) allow their reusability as support materials.

This paper provides a novel approach of using polymer gels as support materials for additive manufacturing processes. These gels are easy to prepare and enhance the sustainability due to their reusability.

Although, MC in water have shown to form gels and these aqueous gels have been used in many applications such as medicine and food industries, the compositions presented in this paper are unique. Such combinations of MC and non‐aqueous solvents (i.e. propylene glycol and butylene glycol) have not been discussed before and provide an early step towards a new application area (i.e. additive manufacturing) for these gels.

The purpose of this article is to evaluate the role of mineralisers on the formation of perovskite structure, optimise the amounts of chromium content, soaking time and finally the ratio of fuel (citric acid) to oxidiser (metal nitrate) and investigation of the physical properties of resulted pigments.

A red pigment based on perovskite structure (YAl_1-yCr_yO₃, y = (0.01-0.1) was synthesised by solution combustion method with various mineralisers, like NaF, MgF₂ and Li₂CO₃. Thermal decomposition of the resulting nitrate-citrate gels and the phase evolution of calcined powders were investigated and the microstructure and colorimetry of the emerging products were characterised.

The most effective mineraliser system for the formation of YAlO₃ perovskite was NaF:MgF₂:Li₂CO₃ (3:2:1 by weight). Furthermore, desirable pigments were obtained by firing the samples at 1,400°C for 4 hours. The highest redness parameter (a*) and reflectance value were obtained when y was 0.03 and 0.01, respectively. Increasing the fuel: oxidiser ratio led to an increase in the a* parameter. Use of the optimum prepared red pigment in the low and high firing temperature glazes gave a high chemical and thermal stability.

Only citric acid was used as fuel. Other fuels and different ratios of fuel to oxidiser could also be studied.

The method developed provided a new approach for preparation to nontoxic, high-temperature, ceramic red pigment compared to the solid-state method.

The methods for synthesis of pigment based on perovskite structure with different chromium contents and for evaluation of thermal stability of pigment in glaze were novel.

The purpose of this paper is to prepare superabsorbent polymers (SAPs) based on acrylic acid, which is considered hygroscopic material to incorporate in rubber formulation, which results in producing moisten rubber that is used as roofing sheets.

SAPs were synthesized via free radical bulk polymerization technique using different content of cross-linker N, N'-methylenebisacrylamide and potassium persulfate. Differential scanning calorimeter, thermal gravimetric analysis, Fourier transform infrared spectroscopy and transmission electron microscopy were used to characterize SAPs and confirmed the formation of cross-linked hydrogel structure. The water absorbency and the gel fraction for sodium polyacrylate (NaPA) were investigated. Then, the influence of obtained NaPA on the swelling behavior of the prepared natural rubber (NR) compound has been discussed.

Absorption characteristics and gel fraction of NaPA were found to depend on the content of the cross-linker in the system. SAPs are used to improve the absorbance behavior and performance of the NR to produce, roofing sheets using in hot weather. The morphology of the obtained rubber compound was well-explained by using a scanning electron microscope.

The research provides a simple way to produce moisten rubber that can be used as a roofing sheet to overcome warm weather.

Moisten rubber roofing sheets provide a low-cost option in many developing countries with hot climates, and thus, help save the environment from global warming.

To prepare of fine particle size magnesium ferrite pigments by sol‐gel method.

Different magnesium ferrite pigments with stoichiometric ratios were prepared by sol‐gel and dispersion methods. The characterisation of magnesium ferrite pigments were based on X‐ray diffraction, transmission electron microscope, particle size distribution, thermal and magnetometric analyses.

The type of polymer and the starting inorganic materials (oxides or salts) have a significant effect on the properties of the magnesium ferrite pigments prepared.

The magnesium ferrite pigments, prepared and used in the work reported here were synthesised from magnesium and iron oxides, oxalates and chlorides. Urea formaldehyde resin and acrylic polymer were used as the dispersing media. Various other materials, e.g. carboxymethyl cellulose, ethoxy methyl cellulose, polyvinylalcohol and 2‐hydroxyethyl methacrylate and polyacrylamide can also be used to achieve similar effect.

The sol‐gel method provided a fine particle size and different particle shapes. Therefore, the method of preparation could be used to produce fibres, films and monoliths.

The magnesium ferrite pigments prepared could be use in numerous paints for steel protection.

Aloe vera gel has nutritional and therapeutic properties due to presence of bioactive components. The aim of this study is to investigate the effect of pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

Aloe vera gel juice (Aloe barbadensis Miller) was pasteurized at 90°C for 1 min and stored up to 30 days at 4 and 25°C. The effect of pasteurization and storage time on glucomannan, vitamin C, DPPH inhibition (percent) and color of the juice was evaluated.

The results showed that pasteurization reduced vitamin C content and antioxidant activity 16% and 57%, respectively. During storage at 4 and 25°C, vitamin C and glucomannan contents reduced from 84.47 to 54.96 and 46.82 mg vitamin C/100 g dm and from 2.11 to 1.77 and 1.71 g/L, respectively. DPPH inhibition (percent) and Browning index (BI) increased significantly at both storage temperatures, which was more intensive at 25 than 4°C.

This paper is believed to be the only one which investigates the effect of thermal pasteurization and storage time at different temperatures on some bioactive components of Aloe vera gel juice.

The purpose of this paper is to examine the preparation of adhesive by incorporation of kraft lignin as an agricultural waste into phenol formaldehyde (PF) resin structure and to evaluate the mechanical properties of lignin phenol formaldehyde (LPF) as wood adhesive.

PF resin (resole) was prepared using sodium hydroxide as a catalyst. Different concentrations of lignin were incorporated into PF resin structure. The effect of lignin concentration, formaldehyde to phenol molar ratio, catalyst concentration, temperature and time upon solid content, adhesive strength and gel time was studied. The kraft lignin, PF and LPF resins were characterised using FT‐IR and thermal analysis.

The incorporation of lignin into PF resin (resole) increases adhesive strength and decreases gel time. The highest adhesive strength and the lowest gel time were achieved at 90 per cent of kraft lignin, formaldehyde to phenol molar ratio, 7.2 and 10 per cent of catalyst, after 4 h and at 80°C.

The effect of different concentrations of kraft lignin, formaldehyde/phenol molar ratio, catalyst concentration, temperatures and time upon solid content, gel time and adhesive strength was studied.

Incorporation of kraft lignin into resole leads to adhesive with improved mechanical properties.

It was found that LPF resin is better than PF resin from the economical point of view and has the better mechanical properties.

The purpose of this paper is to develop and test the thermal interface materials (TIM) for application in assembly of semiconductor chips to package. Good adhesion properties (>5 MPa shear strength) and low thermal interface resistance (better than for SAC solders) are the goal of this research.

Mechanical and thermal properties of TIM joints between gold plated contacts of chip and substrate were investigated. Sintering technique based on Ag pastes was applied for purpose of this study. Performance properties were assessed by shear force tests and thermal measurements. Scanning electron microscopy was used for microstructural observations of cross-section of formed joints.

It was concluded that the best properties are achieved for pastes containing spherical Ag particles of dozens of micrometer size with flake shaped Ag particles of few micrometers size. Sintering temperature at 230°C and application of 1 MPa force on the chip during sintering gave the higher adhesion and the lowest thermal interface resistance.

The new material based on Ag paste containing mixtures of Ag particles of different size (form nanometer to dozens of microns) and shape (spherical, flake) suspended in resin was proposed. Joints prepared using sintering technique and Ag pastes at 230°C with applied pressure shows better mechanical and thermal than other TIM materials such as thermal grease, thermal gel or thermally conductive adhesive. Those material could enable electronic device operation at temperatures above 200°C, currently unavailable for Si-based power electronics.

The purpose of this study was to prepare colour pigments for use as spectrally selective coatings for solar absorbers.

Nano-particles cobalt and nickel oxides were prepared by sol–gel techniques. These oxides were prepared with its molar ratios and annealed at 200, 400, 600 and 800°C. The structure of the pigments was characterized by infrared spectrometer, differential scanning calorimetry analysis, X-ray diffraction, transmission electron microscope and scanning electron microscope.

Encapsulated cobalt and nickel oxides were completely formed at 800 and 600°C, and its colour was black and dark green, respectively. The results confirmed that black and green pigments combined selectivity with colour. Optical properties such as absorption and reflection were affected by the firing temperatures on cobalt and nickel oxides–gel polymers. All synthesized pigments consisted of nano-particles.

The prepared samples used in the present work were synthesized from cobalt chloride and nickel acetate. The salts were dispersed in polyacrylamide as a precursor.

The prepared metal oxides had good solar properties.

Colour becomes more important for thermal solar collectors, and it has attracted interest. This might be related to a generally growing attention towards architectural integration of solar energy systems into building. Architects would prefer different colours besides black, even if lower efficiency would have to be accepted.

The purpose of the work reported in this paper is to prepare hybrid pigments fabricated by depositing pigment yellow 12 (PY12) on the surface of silica gel to improve the application performance of the resulting pigments. The particle size distribution, optical properties, thermal stability, water dispersibility and flowability of the pigments with and without silica gel modification were studied.

The hybrid pigments were synthesised with different amount of silica gel. The modified pigments were characterised by Fourier transforms infrared spectroscopy, X-ray diffraction, thermal analysis, scanning electron microscopy and transmission electron microscopy.

The particle size distribution of the modified pigments was found to have been altered significantly. This can be explained by the interaction between pigments and silica gel, which prevented self-aggregation of pigment particles and hence improved the properties of pigments.

Only silica supports and pigment yellow 12 were evaluated. Other pigments could also be studied.

Modification of pigment particles with smaller particle size can increase the efficiency of the modified pigment, in terms of colour shade and tinting strength, due to better particle size distribution.

The paper demonstrates that inorganic core can prevent self-aggregation of pigment particles, and the application properties of such pigment depend on the resulting degree of dispersion of pigment particles.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.