Polystyrene pellets

Conveying capacity expressed as vol % of solids in the stream usually is well under 5 vol %. From Table 5.1, for example, it is about 1.5% for alumina and 6.0% for polystyrene pellets, figured at atmospheric pressure at 12psig these percentages will be roughly doubled, and at subatmospheric pressures they will be lower. 

Results. Figures 3-5 and Table Vm display the results for the SFE and Soxhlet extraction of polywax 1000 and mekon waxes from polystyrene pellets. 

Figure 11.2. Rates of desorption of gases from polystyrene pellets and granules. Samples of solid polystyrene were saturated with gas at high pressure prior to measurement. The sample weights are measured continuously as gas desorbs from the sample at room temperature and atmospheric pressure. The label pellets refers to the 1/8 in x 1/8 in diameter polystyrene pellets received from the manufacturer, while granules refers to pellets ground to approximately 14 mesh size. Data from Kwag (1998).

Foamed polystyrene sheet and fUm are manufactured by a tubular fUm-extrusion process using conventional methods with specially treated expandable-polystyrene pellets, or by injecting a propellant directly into a section of the extruder barrel with standard polystyrene resins and additives. In both techniques the extrudate passes through an annular tubing die and is expanded, either by blowing air inside the tube, or by drawing the tube over an internal sizing mandrel (6). 

Polystyrene pellets can be impregnated with isopentane at room temperature and modest pressure. When the pellets are heated, they can be made to fuse together at the same time that the isopentane evaporates, foaming the polystyrene and cooling the assembly at the same time. Usually the pellets are prefoamed to some extent before being put into a mold to form a cup or some form of rigid packaging. 

Figure 4 The apparent heat capacity at 20K/min. of compressed polystyrene pellets (M = 110,000) as a function of the room temperature aging time.

Purpose Raw materials storage Removal of impurities Polymerisation of styrene Recoyery of umeacted styrene and solvent Formation of polystyrene pellets Storage of bulk PS Packaging of PS pellets... 

The particles used in this ejqjeriment is spherical polystyrene pellets of which mean diameter is 1.65 mm and material density is 1034 k m. The terminal settling velocity in a room air is calculated as 6.5 m/s and the saltation velocity by Zenz [14] is 3.0 m/s. Thus, the particle is said to be coeirse. 

Figure 13.11 (a) ATR spectrum of a polystyrene pellet and (b) transmission spectrum of a... 

Polystyrene pellets have been nitrated using similar procedure and then aminated ... 

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