Surprisingly, we found that the solutions with a higher viscosity than water had either less or the same surface tension as water, and we suspect this is due to the unchanged intermolecular bonding of water molecules hydrogen bonding causing surface tension as viscosity increased.
A possible explanation is that the viscosity of a fluid is influenced more by the friction caused by the interactions between large molecules with a lot of polar atoms, causing attraction between them. After that, things start to get murky.
Let us start with surface tension. This ever-present property is caused by unbalanced forces on surface molecules that pull toward the main part of the liquid. This is caused by the friction between molecules. Compared to viscosity, surface tension is a simpler phenomenon. It is basically stable, changed mostly by temperature and chemicals that modify the bonding characteristics of the molecules.
As temperature decreases , surface tensio n increases. The effects of adding an unrelated substance is illustrated by the example of putting soap a surfactant in water to reduce the surface tension, which allows the dirt on your hands to more easily mix with the water. Regarding viscosity , knowing the type of liquid is essential. After drying, the gum was powdered and passed through sieve.
Dried gum was stored at room temperature in air tight containers [8]. The intrinsic viscosity is a measure of the hydrodynamic volume which is occupied by the macromolecule related closely to the confirmation and size of chains of macromolecule in its specific solvent system. It facilitates measurement of size as well as confirmation of chains of macromolecules [9].
Then expression can be represented as Huggins equation [10]. Graphical relationship between ln relative viscosity and concentration estimated on extrapolation of line to zero concentration [11]. It gives ln intrinsic viscosity, determined through the following equation-. Other viscosities can also be estimated such as the relative viscosity; the specific viscosity; the inherent viscosity; and the reduced viscosity.
The relative viscosity is the ratio of the viscosity of a solution to the viscosity of solvent used. It can be determined by using the eqn 4. Figure 2a shows the. Specific viscosity can be expressed as the ratio of absolute viscosity of fluid that of a reference. It can also be determined by:. The inherent viscosity is the ratio of the natural logarithm of the relative viscosity to the mass concentration of gum.
The reduced viscosity is equal to the ratio of relative viscosity increment to the mass concentration of gum. It provides information regarding polysaccharide confirmation [10]. The molecular conformation and the coil overlap can be estimated via the power law model equation shown in the following equation has greater utility in studying molecular interactions are in the solution of polymer and its confirmation.
The surface tension is another important parameter to be considered during formulation of better products. The chemistry which deals with surface properties, interface mechanism between two phases.
The chemistry deals with chemical processes at the interface between two phases [12]. The surface tension of gum solution determined using a Stalagmometer and formula:.
Equation Rheology involves Concentration -dependent viscosity determination. It serves as main tool to establish rheological behavior of products [9]. Viscometers are used to determine viscosity. Viscosity is determined through Ostwald viscometer. It has been shown in following figure 1a that increase in relative viscosity of gum is observed, as we increase the concentration of the gum.
It is due to increment at internal resistance flow of gum and an exertion of intermolecular friction between fluids layers which are slide over one another. Observed values gives direct relationship between viscosity with concentration while inverse relationship between concentration and the surface tension.
The intrinsic viscosity can be estimated from intercept Figure 1a and was found to be 0. The value of Huggins constant is 0.
Kraemer constant estimated from equation-3 shown in figure 1b. The value observed is about 0. The intrinsic viscosity can also be determined from the Kraemer equation, gives the line between ln relative viscosity and concentration and fitting to kraemer equation. This equation provides the information regarding molecular association between gum molecules [14].
The intrinsic viscosity can also be estimated from intercept. The intercept from figure 1a is found to be 0.
The KH value can be calculated from equation The value of k H observed is 0. TL;DR Too Long; Didn't Read As the temperature rises, liquids lose viscosity and decrease their surface tension — essentially, becoming more "runny" than they would be at cooler temps. HDPE Vs. What Determines the Viscosity of a Fluid?
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