Effect of Water Glass Modification on Its Viscosity and Wettability of Quartz Grains

Abstract

The aim of the present study was to develop a modifier for water glass. The method of thermal generation of metal oxide nanoparticles was adapted and used in the research. Nanoparticles of ZnO from the thermal decomposition of basic zinc carbonate were used. A method for the modifier introduction was developed, and the effect of modifier content and organic solvent type on the physico-chemical properties of binder (viscosity) and quartz wettability was determined. Binder viscosity was examined from the flow curves plotted with the help of a RHEOTEST 2 rotational rheometer equipped with proper software. Quartz wettability was determined examining timerelated changes in the value of the contact angle in a quartz-binder system, until full stabilisation of the angle value has been achieved. Binder modification was carried out on sodium water glass designated as R"145". The water glass modifiers were suspensions of ZnO nanoparticles in propanol and methanol at a fixed concentration of c = 0.3 M and with the size of nanoparticles comprised in a range of <61 - 981 nm>. Water glass modification with the suspensions of ZnO nanoparticles in methanol and propanol showed the effect of modifier on the water glass viscosity and quartz wettability. This effect depends on the type of alcohol used. The ZnO suspension in propanol (alcohol with a longer hydrocarbon chain) affects more strongly the viscosity of binder and quartz wettability than the methanol suspension

Experimental Study of Inorganic Foundry Sand Binders for Mold and Cast Quality

“…2 The introduction of nanoparticles creates new systems known as nanocomposites, which modifies the properties of the binder in the interface layers, improving mechanical and thermal properties of the binder. 17 Tensile strength, flowability, and collapsibility behavior of sodium silicate bonded core was shown to be improved through the addition of potassium hydroxide, sodium hexametaphosphate, and white sugar modifiers in. 18 Commercial brands of heat-hardened sodium silicate binders also exist that come in the form of a modified sodium silicate binder and a solid promoter as second component of the binder.…”

“…Surface roughness can be visually inspected and compared; differences evident in Figures 15,16,and 17. Differences can also be seen in 3D scan results of the castings when the differences are relatively large.…”

Archives of Foundry Engineering

“…One such example is hydrated sodium silicate; cheap, easily accessible and non-toxic. However, the unfavorable feature of the hydrated sodium silicate moulding sands is their fragility, poor knock-out properties and low ability to mechanical regeneration [1,5]. Previous studies have focused on the development of methods to improve the knock-out properties of these moulding mixtures and the quality of their reclaim.…”

“…Literature [7][8][9][10] shows that biodegradable materials can be used as additives in petroleum based binders to cause biodegradation of the ingredients from the petrochemical industry. One of the examples is polycaprolactone (PCL), which is compatible with many other polymers [5]. Studies on the biodegradability of PCL blends with other polymers have been presented in the work of Iwamoto and Tokiwa [11].…”

Effect of Sand Wetting on Physically Hardened Moulding Sands Containing a Selected Inorganic Binder. Part 1

“…Apart from viscosity, spreading of the binder depends on many other factors, like temperature of binder, temperature of base [8], morphology of base grain surfaces [9], way of stirring and sequence of introducing liquid components of the sandmix [9], and grade of water-glass [7,10]. Moreover, it was shown in [11,12] that modification of water-glass influences wettability and viscosity of the binder. Of particular importance for quality of the manufactured sandmixes containing water-glass are also special additives [13 -16 ] intentionally introduced at the stirring stage in order to improve their knocking-out properties.…”