This simple technqie was found discriminate sucessfully plastic particle sizes, less than 1mm, 1.5mm and above 1.5mm.With the use of less volatile solvents
, the choice of the most suitable evaporating area and some caliberation, the method is expected to be useful to discriminate effectively plastic grain sizes.
Thirty-eight percent of Aboriginal users were found to inhale volatile solvents
on a daily basis, as compared with 23% of non-Aboriginal users.
The act of bagging may result in asphyxia, as the partial pressure of the volatile solvent
displaces oxygen at a critical level (Linden, 1990).
With the Unicarb technology, supercritical [CO.sub.2] is used to replace the volatile solvent
fraction in coating formulations that is needed to obtain low spray viscosity.
The choice of volatile solvent
is very limited because most of known volatile solvents
for polymers are not miscible with water.
This is achieved using a special holder for vials that allows a selection of baffles to be placed on top of the vial to slow the evaporation rate of the volatile solvents
. Size and number of baffles are selected to be most restrictive for the most volatile solvents
, and least restrictive for the less volatile solvents
(a) NO = Nitrous Oxide; VS = Volatile Solvents
. (b) AB = Lifetime Users of NO and VS Inhalants vs.
Witco has a new liquid Ba/Zn, Mark 4794, which contains no volatile solvents
. It's aimed at general-purpose flexibles where VOC requirements are critical.
Although blow down evaporation is relatively fast for volatile solvents
, it can be slow for solvents with high boiling points or those that are difficult to evaporate, such as water.
Highly volatile solvents
(large [[p.sub.1].sup.o]) evaporate quickly, giving thicker films (also somewhat rougher) and smaller values for [[t.sup.*].sub.p] than less volatile solvents
for similar [[x.sub.1].sup.0] values.