scholarly journals Assessment of Influence and Threshold Ratios of Titanium Dioxide and Calcium Carbonate as Pigments on the Physico-Mechanical Properties of Emulsion Paint

Author(s):  
A.A Raheem ◽  
O.A Olowu ◽  
A.E. Aladeloba ◽  
A.A Hungbo ◽  
A.Y Akinsanya

Titanium dioxide (TiO2) also known as Titanium White, is an inorganic, synthetic pigment used in paint to protect the substrate from harmful effects of ultraviolet light when lead pigments are regarded as toxic. However, its use is being limited since it causes flu-like symptoms, respiratory problem and skin irritation. Calcium carbonate (CaCO3) is a chemical commonly used as an extender pigment in cement to provide bulkiness at relatively low cost. Because of the problem associated with TiO2, it is of importance to regulate and optimize the use of TiO2 relative to CaCO3 and their influence on the physico-mechanical properties of emulsion paints. Nine paint specimens were formulated using 0 – 80 grams per litre of TiO2 and 120 – 200 grams of CaCO3, respectively at 10 gram interval. The following tests were performed on them: specific gravity, viscosity, pH, surface drying time, hard drying time, wash-ability/adhesion and opacity tests, in accordance to Nigerian Industrial Standard (NIS) 278: 1990. The result shows that all samples met specifications of 10 poise maximum, 5%, 7.5-9.0, 20 minutes, 2 hours, and 201 minimum, for viscosity, specific gravity, pH, surface drying time, hard drying time and wash-ability/adhesion properties, respectively. However, six sample specimens only met the requirement of NIS 278:1990 of 2coats for good opacity. In conclusion, TiO2 has no negative effect on the other physio-mechanical properties except the opacity of the paint and so specimens 7, 8 and 9, and ratio 30:170 is considered the threshold values for the paint production.

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Jong Sung Won ◽  
Ji Eun Lee ◽  
Da Young Jin ◽  
Seung Goo Lee

The effective utilization of original natural fibers as indispensable components in natural resins for developing novel, low-cost, eco-friendly biocomposites is one of the most rapidly emerging fields of research in fiber-reinforced composite. The objective of this study is to investigate the interfacial adhesion properties, water absorption, biodegradation properties, and mechanical properties of the kenaf/soy protein isolate- (SPI-) PVA composite. Experimental results showed that 20 wt% poly (vinyl alcohol) (PVA) and 8 wt% glutaraldehyde (GA) created optimum conditions for the consolidation of the composite. The increase of interfacial shear strength enhanced the composites flexural and tensile strength of the kenaf/SPI-PVA composite. The kenaf/SPI-PVA mechanical properties of the composite also increased with the content of cross-linking agent. Results of the biodegradation test indicated that the degradation time of the composite could be controlled by the cross-linking agent. The degradation rate of the kenaf/SPI-PVA composite with the cross-linking agent was lower than that of the composite without the cross-linking agent.


2018 ◽  
Vol 930 ◽  
pp. 270-275 ◽  
Author(s):  
Victor Rafael Leal Oliveira ◽  
M.K.S. Monteiro ◽  
F.K.G. Santos ◽  
R.H.L. Leite ◽  
E.M.M. Aroucha

Coating technologies with biopolymeric films of low cost and high efficiency are effective in maintaining the chemical and sensory characteristics and shelf-life extension of several fruits.Films of cassava starch/glycerol were synthesized at different temperature and time conditions (25oC / 60h, 40oC / 5h, 60oC / 3h and 80oC / 2h) in order to decrease the drying time of the filmogenic solutions.SEM analysis (scanning electron microscopy), WVP (water vapor permeability), wettability and mechanical properties were evaluated in order to identify morphological and structural changes in the polymeric matrix in different conditions.Changes in temperature and drying time significantly reduced the roughness and affected the barrier characteristics, effectively improving tensile strength. A reduction of more than 90% in the drying time was identified.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
O. J. Gbadeyan ◽  
S. Adali ◽  
G. Bright ◽  
B. Sithole ◽  
S. Onwubu

The possibility of obtaining calcium carbonate nanoparticles from Achatina fulica shell through mechanochemical synthesis to be used as a modifying filler for polymer materials has been studied. The process of obtaining calcium carbonate nanopowders includes two stages: dry and wet milling processes. At the first stage, the collected shell was dry milled and undergone mechanical sieving to ≤50 μm. The shell particles were wet milled afterward with four different solvents (water, methanol, ethylene glycol, and ethanol) and washed using the decantation method. The particle size and shape were investigated on transmission electron microscopy, and twenty-three particle counts were examined using an iTEM image analyzer. Significantly, nanoparticle sizes ranging from 11.56 to 180.06 nm of calcium carbonate was achieved after the dry and wet milling processes. The size particles collected vary with the different solvents used, and calcium carbonate synthesis with ethanol offered the smallest organic particle size with the average size ranging within 13.48-42.90 nm. The effect of the solvent on the chemical characteristics such as the functional group, elemental composition, and carbonate ion of calcium carbonate nanopowders obtained from Achatina fulica shell was investigated. The chemical characterization was analyzed using Fourier transform infrared (FTIR) and a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscope (EDX). The effect of milling procedures on the mechanical properties such as tensile strength, stiffness, and hardness of prepared nanocomposites was also determined. This technique has shown that calcium carbonate nanoparticles can be produced at low cost, with low agglomeration, uniformity of crystal morphology, and structure from Achatina fulica shell. It also proved that the solvents used for milling have no adverse effect on the chemical properties of the nano-CaCO3 produced. The loading of calcium carbonate nanoparticles, wet milled with different solvents, exhibited different mechanical properties, and nanocomposites filled with methanol-milled nano-CaCO3 offered superior mechanical properties.


2018 ◽  
Vol 47 (6) ◽  
pp. 478-484 ◽  
Author(s):  
Norshahirah Mohamad Saidi ◽  
Ammar Shafaamri Shafaamri ◽  
Iling Aema Wonnie Ma ◽  
Ramesh Kasi ◽  
Vengadaesvaran Balakrishnan ◽  
...  

Purpose The purpose of this study is to develop anti-corrosion coating systems using disposable waste materials. The dissolved polyethylene terephthalate (PET) has been blended with epoxy resin and stoichiometrically cured with a polyamide resin. Design/methodology/approach Glycolysis process was found to be the most optimum candidate to dissolve PET. The developed coating systems were characterized by Fourier transform infrared spectroscopy for confirmation of the molecular bonding structures. The mechanical properties were characterized by performing pull-off test and cross hatch test for mechanical properties on the coated panel. Also, the glossiness test was used by reflecting light on the coated surface. The corrosion protection performance of the coated mild steel panels was examined using electrochemical impedance spectroscopy. Furthermore, the wettability of the developed coating systems was evaluated by using water contact angle technique. Findings It was observed that the coating system which contains 10 per cent of dissolved PET (S2) showed the highest adhesion and corrosion protection properties. Originality/value Recyclable PET bottles have outstanding chemical properties, adhesion properties, low cost, low permeability to gases and solvents making it suitable as a coating with superior barrier properties.


TAPPI Journal ◽  
2014 ◽  
Vol 13 (2) ◽  
pp. 17-25
Author(s):  
JUNMING SHU ◽  
ARTHAS YANG ◽  
PEKKA SALMINEN ◽  
HENRI VAITTINEN

The Ji’an PM No. 3 is the first linerboard machine in China to use multilayer curtain coating technology. Since successful startup at the end of 2011, further development has been carried out to optimize running conditions, coating formulations, and the base paper to provide a product with satisfactory quality and lower cost to manufacture. The key challenges include designing the base board structure for the desired mechanical strength, designing the surface properties for subsequent coating operations, optimizing the high-speed running of the curtain coater to enhance production efficiency, minimizing the amount of titanium dioxide in the coating color, and balancing the coated board properties to make them suitable for both offset and flexographic printing. The pilot and mill scale results show that curtain coating has a major positive impact on brightness, while smoothness is improved mainly by the blade coating and calendering conditions. Optimization of base board properties and the blade + curtain + blade concept has resulted in the successful use of 100% recycled fiber to produce base board. The optical, mechanical, and printability properties of the final coated board meet market requirements for both offset and flexographic printing. Machine runnability is excellent at the current speed of 1000 m/min, and titanium dioxide has been eliminated in the coating formulations without affecting the coating coverage. A significant improvement in the total cost of coated white liner production has been achieved, compared to the conventional concept of using virgin fiber in the top ply. Future development will focus on combining low cost with further quality improvements to make linerboard suitable for a wider range of end-use applications, including frozen-food packaging and folding boxboard.


Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1369
Author(s):  
Sanjeev Kumar ◽  
Lalta Prasad ◽  
Vinay Kumar Patel ◽  
Virendra Kumar ◽  
Anil Kumar ◽  
...  

In recent times, demand for light weight and high strength materials fabricated from natural fibres has increased tremendously. The use of natural fibres has rapidly increased due to their high availability, low density, and renewable capability over synthetic fibre. Natural leaf fibres are easy to extract from the plant (retting process is easy), which offers high stiffness, less energy consumption, less health risk, environment friendly, and better insulation property than the synthetic fibre-based composite. Natural leaf fibre composites have low machining wear with low cost and excellent performance in engineering applications, and hence established as superior reinforcing materials compared to other plant fibres. In this review, the physical and mechanical properties of different natural leaf fibre-based composites are addressed. The influences of fibre loading and fibre length on mechanical properties are discussed for different matrices-based composite materials. The surface modifications of natural fibre also play a crucial role in improving physical and mechanical properties regarding composite materials due to improved fibre/matrix adhesion. Additionally, the present review also deals with the effect of silane-treated leaf fibre-reinforced thermoset composite, which play an important role in enhancing the mechanical and physical properties of the composites.


Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 887
Author(s):  
Chunhua Feng ◽  
Buwen Cui ◽  
Haidong Ge ◽  
Yihong Huang ◽  
Wenyan Zhang ◽  
...  

Recycled aggregate is aggregate prepared from construction waste. With the development of a global economy and people’s attention to sustainable development, recycled aggregate has shown advantages in replacing natural aggregate in the production of concrete due to its environmental friendliness, low energy consumption, and low cost. Recycled aggregate exhibits high water absorption and a multi-interface transition zone, which limits its application scope. Researchers have used various methods to improve the properties of recycled aggregate, such as microbially induced calcium carbonate precipitation (MICP) technology. In this paper, the results of recent studies on the reinforcement of recycled aggregate by MICP technology are synthesized, and the factors affecting the strengthening effect of recycled aggregate are reviewed. Moreover, the strengthening mechanism, advantages and disadvantages of MICP technology are summarized. After the modified treatment, the aggregate performance is significantly improved. Regardless of whether the aggregate was used in mortar or concrete, the mechanical properties of the specimens were clearly improved. However, there are some issues regarding the application of MICP technology, such as the use of an expensive culture medium, a long modification cycle, and untargeted mineralization deposition. These difficulties need to be overcome in the future for the industrialization of regenerated aggregate materials via MICP technology.


2016 ◽  
Vol 29 (1) ◽  
pp. 26-35 ◽  
Author(s):  
Yunwu Yu ◽  
Wenhao Pan ◽  
Xiaoman Guo ◽  
Lili Gao ◽  
Yaxin Gu ◽  
...  

Poly(arylene ether sulfone) (PES)–titanium dioxide (TiO2) hybrid membranes were prepared via solution blending method using TiO2 nanoparticles as inorganic filler. The chemical structure and thermal stability of the matrix polymer were characterized by proton nuclear magnetic resonance, Fourier transform infrared, differential scanning calorimetry, and thermogravimetric analysis. The crystal structure, morphology, mechanical properties, and gas separation performance of hybrid membranes were characterized in detail. As shown in scanning electron microscopic images, TiO2 nanoparticles dispersed homogeneously in the matrix. Although the mechanical properties of hybrid membranes decreased certainly compared to the pure PES membranes, they are strong enough for gas separation in this study. All gas permeability coefficients of PES-TiO2 hybrid membranes were higher than pure PES membranes, attributed to the nanogap caused by TiO2 nanoparticles, for instance, oxygen and nitrogen permeability coefficients of Hybrid-3 (consists of PES with 4-amino-phenyl pendant group and hexafluoroisopropyl (Am-PES)-20 and TiO2 nanoparticles, 5 wt%) increased from 2.57 and 0.33 to 5.88 and 0.63, respectively. In addition, the separation factor increased at the same time attributed to the stimulative transfer effect caused by the interaction of hydroxyl groups on the TiO2 nanoparticle and polar carbon dioxide molecules.


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