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It is well-known that asbestos such as asbestosis and mesothelioma is a fiber causing lung diseases. Talc is used for commercial applications for example paints, plastics, papers, ceramics, construction materials, and cosmetics. It is well-known that the cosmetic talc powder is used for preventing diaper rash as a deodorant. The sampling in this work has been done from various commercial products in Thailand. Their microstructure and elemental composition are analyzed using a scanning electron microscope coupled with an energy dispersive X-ray spectrometer (SEM-EDS). A small-angle X-ray scattering (SAXS) and infrared spectroscopy (IR) based on synchrotron radiation are also carried out to determine their phase composition and functional groups. It has been found that fibers with asbestos-like shapes are present in some samples. The main composition of oxygen, silicon, and magnesium in samples are in the form of the functional groups that associate with absorption band in the range of 3600-3700 cm -1 of IR spectra. It is proposed that there are 6 from 17 samples that possibly have asbestos contamination.

This study aims to verify the possibility of replacing a portion of zinc (up to 30 wt.%) with a newly designed micro talc/polyaniline (PANI) core-shell pigment that can be used in the protective primer compositions for metals. Measurements of the electrode potential of painted steel and the electrical capacity of the steel/coating/electrolyte system showed that synthesized pigment bears two functions. Firstly, its presence in the epoxy-amine coatings provides a cathodic protection mechanism for steel with the lower zinc content. Secondly, it allows long-term preservation of the sacrificial metal activity and passive state of the substrate due to the autocatalytic redox cycle based on the reversible conversion of PANI from its emeraldine to leucoemeraldine form. The corresponding mechanism that allows the retaining of sacrificial metal activity and the passive state of the substrate is proposed.

Polypropylene is commonly employed in several industrial applications such as packaging, cable insulation and automotive. Research interest has focused on how to improve its mechanical properties to reduce the effect of low impact toughness of polypropylene. One of the sustainable ways to achieve this is by incorporating graphene nanoplatelets to form a composite. This study investigates the application of a hybrid support vector machine (SVM) and artificial neural networks (ANN) model to predict the effect of incorporating graphene on the mechanical properties of polyproline composites. The effect of parameters such as maleic anhydride grafted polypropylene (MAPP), Talc, and exfoliated graphene nanoplatelets on the tensile strength and modulus of the polypropylene composites was modelled by using ANN. Testing various topologies was accomplished. An optimized ANN structure of 3-7-2 indicating 3 input-layer, 7 hidden layer, and 2 output-layer was tested. Both the SVM and the ANN predict well the mechanical properties of polyproline composites. However, the ANN with R2 of 0.999 offers the best predictions.

Aluminium matrix composites (AMC) strengthened with hard particles has given rise to a potential material particularly for wear resistant and weight basic applications. The effect of heat treatment of aluminium alloys sliding wear nature are observed under varying load and speed. Irrespective of materials heat treatment improves hardness of the material. The particulate reinforcements embedded with Al2218 Aluminium metallic element alloy with 4% constant weight proportion of Talc, Boron Nitride and a variable amount of hard reinforcement particulates. By introducing fly ash as reinforcement satisfies the structural and thermal properties. 5%, 10% & 15% of fly ash added to the composite by metal stir casting technique. The specimens are treated with ASTM T6 standard. Performance of heat-treated matrix composite was investigated with a pin on disc apparatus through a constant load 2 kg and with a desirable rpm. Hardness of the specimen at temperature were measured before and once the heat treatment. Heat treated metal exhibits high hardness and wear resistance. This investigation reveals that 2218 Aluminium matrix composites with high hardness and wear resistance will replace the material employed in Automobiles like brake drum, cylinder block, connecting rod, piston etc for higher performance and longer life.

In this study, epoxy resin blended with graphite/talc micro fillers are used to fabricate the composite bearing balls of uniform diameter of 12.7 mm. These bearing balls were tested in four ball test rig for investigation of friction and wear. The fabricated composite bearing ball of composition graphite (10 wt%) /talc (10 wt%)/epoxy demonstrated a significant reduction by ∼63% in coefficient of friction and a moderate increment by ∼34% in wear resistance as compared to pure epoxy bearing ball under dry condition. Further, the compressive strength and hardness test were carried out on the composite bearing balls which revealed a reduction in compressive strength after adding the fillers but approximately similar compressive strength and a marginal improvement in hardness by ∼5% was exhibited by graphite (10 wt%)/talc (10 wt%) /epoxy composite bearing ball with respect to pure epoxy bearing ball. Hence, the fabricated polymer composite bearing balls can be implemented for low to moderate load bearing application with enough capability to eliminate the bulk lubrication requirements as in case of conventional metallic bearing balls.

The foamed wood-polymer composites with polypropylene (PP) and polyolefin elastomer (POE) blends as matrix were prepared by a co-rotating twin-screw extruder and a single-screw extruder foaming system in this paper. To improve the dispersion uniformity of materials in the samples, a cavity transfer mixer was introduced to the single-screw extruder foaming system. Besides, the effects of both the nucleating agent and the coupling agent on the melt flowability, cell morphology and mechanical properties of the samples were investigated. The nanoparticles were also added to study the effect of nano-nucleating agent on the properties of the foamed samples. The experimental results show that the addition of talc and maleic anhydride grafted polypropylene (MAH-g-PP) resulted in the decrease of the melt flow rate and the increase of the Vicat softening temperature. But the addition of nanoparticles improved the melt flowability and reduced the softening temperature of the samples. Compared with talc, the addition of nanoparticles increased the impact strength of the samples by 6%. Moreover, the minimum cell size and the maximum cell density were obtained with the value of 62 μm and 2.8 × 104 cells cm−3, when the content of both talc and MAH-g-PP were 10 phr. Affected by the cell morphology, the maximum impact strength, tensile strength and flexural strength of the samples were also obtained with the value of 6.6 kJ m−2, 8.3 MPa and 22.6 MPa.

Properties of sandwich structures with a core of thermoplastic foam depends on cell size and cell density (cell number). Nucleating agents have a benefit to generate cell nucleation, which affects an increase in the cell density. In this study, sandwich structures composed of a polypropylene (PP) foam core and organic sheet skins in-situ produced by injection moulding process. A chemical blowing agent was employed to generate cellular structure in the core. The influence of the varying nucleating agent content with the same chemical blowing agent content on density, cellular structure and mechanical properties of the sandwich structures were investigated. The talc contents had a slight influence on the density of the sandwich structures. Moreover, flexural modulus and flexural strength of the sandwich structures consisting of the foam core with 4 wt% of talc were higher than the foam core without talc. However, the utilization of these talc contents with PP and the chemical blowing agent had no significant effect on the reduction of the cell size and the increase of the cell density.

Heavy metal pollution in water and soil has been widely concerned by all sides. Heavy Metal passivation agents can change the presence of heavy metals in water and soil, thus reducing mobility, toxicity and bioavailability. In this paper, the application, effect and prospect of using talc to repair heavy metal pollution are introduced, and some problems and prospects of remediation method of heavy metal pollution are prospected.

This work deals with the reactivity of XRD amorphous delaminated and dehydroxylated talc phase (meta-talc), in alkali medium. Talc ore Luzenac H70 was treated in a stirred ball mill (attritor) for 30; 60 and 90 min with subsequent thermal treatment at 700°C; 750°C and 800°C. Reactivity of mechanochemically and thermally treated talc ore in NaOH solution was studied using isothermal calorimetry. An influence of material crystallinity and amount of water coordinated in material structure after milling on its reactivity in alkali medium was studied. Práce se zabývá reaktivitou rentgeno-amorfní delaminované a dehydroxylované mastkové fáze (metamastku) v alkalickém prostředí. Mastková surovina Luzenac H70 byla mechanochemicky aktivována v promíchávaném mlýně (attritoru) po dobu 30, 60 a 90 min a následně byla tepelně upravena při 700 °C, 750 °C a 800 °C. Reaktivita takto připravených vzorků byla v roztoku NaOH byla studována pomocí izotermická kalorimetrie. V rámci práce byl sledován vliv krystalinity připravených vzorků a množství vody ve vzorcích navázané na jejich reaktivitu v alkalickém prostředí.

A golf course with obstacles in the forms of water obstacle and lateral water obstacle marked with the stakes which are called golf course obstacle stake in this study. This study focused on the design and fabrication of the golf course obstacle stake with a solid cylindrical geometry using EFB fiber-reinforced polimeric foam composite materials. To obtain the EFB fiber which is free from fat content and other elements, EFB is soaked in the water with 1% (of the watre total volume) NaOH. The model of the mould designed is permanent mould that can be used for the further refabrication process. The mould was designed based on resin-compound paste materials with talc powder plus E-glass fiber to make the mould strong. The composition of polimeric foam materials comprised unsaturated resin Bqtn-Ex 157 (70%), blowing agent (10%), fiber (10%), and catalyst (10%). The process of casting the polimeric foam composit materials into the mould cavity should be at vertical casting position, accurate interval time of material stirring, and periodical casting. To find out the strength value of the golf course obstacle stake product, a model was made and simulated by using the software of Ansys workbench 14.0, an impact loading was given at the height of 400 mm and 460 mm with the variation of golf ball speed (USGA standard) v = 18 m/s, v = 35 m/s, v = 66.2 m/s, v = 70 m/s, and v = 78.2 m/s. The clarification showed that the biggest dynamic explicit loading impact of Fmax = 142.5 N at the height of 460 mm with the maximum golf ball speed of 78.2 m/s did not experience the hysteresis effect and inertia effect. The largest deformation area occurred at the golf ball speed v = 66.2 mm/s, that is 18.029 mm (time: 2.5514e-004) was only concentrated around the sectional area of contact point of impact, meaning that the golf course obstacle stakes made of EFB fiber-reinforced polymeric foam materials have the geometric functional strength that are able to absorb the energy of golf ball impact.

The dielectric properties of a MgO and Mg(NO3)2 doped and undoped talc are measured as a function of the frequency range 260 kHz-40 MHz. The ´, tan and ac values are given as a function of the firing temperature for a 5.0 MHz constant frequency. In this study the effects of an impurity and the firing temperature on the dielectric properties are also discussed.

We report experimental and theoretical investigations of a new nanomaterial: monolayer and few-layer talc. We show, through atomic force microscopy (AFM) measurements, that natural talc mineral can be mechanically exfoliated down to monolayer flakes. Our AFM-based mechanical characterization also shows that single- and few-layer talc flakes, of several square-microns, present properties similar to those of graphene, BN and MoS2, including the existence of folds and the recently reported negative dynamic compressibility. From first principles calculations, we also predict the mechanical properties of monolayer talc. We obtain theoretical values of monolayer talc breaking strength that are near graphene’s record values and its 2D elastic modulus. We also predict that the flexural rigidity of monolayer talc should be more than thirty times larger than that of graphene, but that it could still be bent to very small curvatures without fracturing.

Cordierite ceramics (2MgO2Al2O35SiO2) were prepared from cordierite waste from refractory industry. The composition of the mixture composed of 70 wt% cordierite waste powder, 23 wt% talc and 7 wt% alumina mixing with binders, plasticizer, lubricant and water to form ceramic dough. The cordierite samples were sintered at 1250-1350 °C for 2 h. All samples were investigated in terms of phase composition, microstructure, bending strength and thermal expansion coefficient. It was found that the sample sintered at 1300 °C achieved the single phase of cordierite with the bending strength of 21.70 MPa and the lowest thermal expansion coefficient of 2.94×10−6 °C−1 observed in this study.

The terahertz time-domain spectroscopy technique is used to test flour/talc powder mixture samples. It is found that the two samples have obvious absorption peaks and different refractive index. The results provided in this paper will help us to study the THz application to the field of food safety.

Mother earth is giving many materials in the natural form as well as in mineral form. Among them the marbles, granites and other variety of slabs for house hold flooring purposes. The people demand for variety of flooring materials leads to develop various types of ceramic tile. In India ceramic tiles industry is one of the fast growing one. More than two hundred units are manufacturing the ceramic tiles situated around Morbi, Rajkot, Gujarat, India. The basic raw materials required for manufacturing the various types of ceramic tiles are natural minerals. The following are the minerals used to manufacture the ceramic tiles i.e. quartz, feldspar, zircon, china clay, talc, grok, Aluminum oxide etc.

High pressure apparatus for generation of pressure to about 10 kbar at a temperature down to 2K was built. Talc and teflon were used as pressure transmitting media. In order to check the homogeneity and plasticity of these pressure transmitting media, the pressure dependence of the superconducting transition temperature of tin was measured. It was found that the homogeneity of these materials was fairly good, and the generated pressure at the liquid helium temperature is about 70% of the value calculated simply from the ratio of load to piston area.

Coefficients of friction between flat mild steel surfaces loaded at an average intensity of 40 lb/in2 at relative velocities of 0.01 cm/sec and 0.4 cm/sec were determined using talc, vermiculite, flake graphite, paraffin wax and various metallic soaps as lubricants. Only graphite, the metallic soaps and paraffin wax were shown to be effective lubricants and paraffin wax was selected for further study under conditions more in conformity with engineering practice. Results are given of tests in which mild steel treated by tin plating, chromium plating and phosphating was continuously reciprocated against mild steel both unlubricated and lubricated with paraffin wax. A phosphated surface, lubricated with paraffin wax, formed the most satisfactory combination and it is suggested that, under the conditions embraced by the experiments, the porous nature of the surface coupled with the rheological properties of the paraffin wax might be the determining factors in performance.