High pressure light scattering

A cross-sectional view of the high-pressure light scattering cell is shown in Figure 1. The cylindrical light scattering cell window was a high-precision sapphire tube with an inside diameter of 1.9 cm and an outside diameter of 3.2 cm. To achieve the... 

Characterisation of kinetics of protein colloidal micellar dissociation has been carried out using high pressure turbidity and high pressure light scattering measurements. [36] Flow and so-called jump methods will be described in more detail below. 

Y. Xiong and E. Kiran, High-pressure light scattering apparatus to study pressure-induced phase separation in polymer solutions. Rev. Sci. Instrum., 69, 1463-1471 (1998). 

High pressure light scattering studies of structural relaxation... 

One of the most important variables which affects the glass transition in addition to temperature is pressure. Light scattering experiments at high pressure are far from routine, but both polystyrene44, and PEA30,52) have now been extensively studied. The shape of the relaxation function for polystyrene was independent of pressure as well as... 

The solid sample is then ground with KBr and is then made into a disc after drying under elevated temperature at high pressures. A blank disc of KBr is prepared which may be put in the path of a reference beam. Discs obtained from a poorly ground mixture scatter more light than they... 

Figure 7.18 Protein-polysaccharide interactions in emulsions subjected to high pressure treatment (HPT). Influence of pH on average effective particle diameter d43 determined by static light scattering (Malvern Mastersizer) in emulsions (20 vol% soybean oil, 0.5 wt% p-lactoglobulin) prepared with untreated protein (open symbols) and high-pressure-treated (800 MPa for 30 min filled symbols) protein in the absence (O, ) and presence (A, ) of 0.5 wt% pectin. Reproduced from Dickinson and James (2000) with permission.

We developed an experimental procedure that can be applied to highly viscous polymer blends. In the DSM micro-extruder [6], polymers are blended in the melt, at the desired temperature and pressure, and injected into a small capillary tube which is immediately sealed with a floating plug. This capillary cell is placed in a small window autoclave and a laser beam enters the capillary cell at the lens-shaped bottom end. The intensity of the light scattered by the polymer system is recorded at two scattering angles (as a function of pressure and temperature). 

The spinodal and the cloud point can be determined as a function of pressure and temperature (up to 150C, 1000 bar) via light-scattering measurements [41]. The intensity of the scattered light of the polymer solution is measured in a high-pressure optical cell during a pressure pulse in the polymer solution. 

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