[Bashir2008]

Hello everyone:

I have a question regarding how to get the bulk and the solid density of some polymers
 
I do have polypropylene and polyethylene pellets and i need to find out the bulk and solid density of these pellets... i know that the easier experiment to do it is to take a certain amount of the pellets and put in a beaker and fill it with a liquid and find out the voulme and the mass of the pellets..,,,etc
 
My question is what is the best liquid to use here as i am looking for something that has a density less  than the pellets..so the pellets wont float
 
Could you please tell me which is the common liquid that i can use ?
 
I tried to use Ethanol but i donot know if the ethanol wont effect the pellets..
Please try to help me
 
Kind regards

[Phlogiston]

Hello everyone:

I have a question regarding how to get the bulk and the solid density of some polymers
 
I do have polypropylene and polyethylene pellets and i need to find out the bulk and solid density of these pellets... i know that the easier experiment to do it is to take a certain amount of the pellets and put in a beaker and fill it with a liquid and find out the voulme and the mass of the pellets..,,,etc
 
My question is what is the best liquid to use here as i am looking for something that has a density less  than the pellets..so the pellets wont float
 
Could you please tell me which is the common liquid that i can use ?
 
I tried to use Ethanol but i donot know if the ethanol wont effect the pellets..
Please try to help me
 
Kind regards

I don't think it'd dissolve in EtOH, but, why not take a pellet, mass it, put it in EtOH for a while, dry it then mass it again?  If the mass changes then some dissolved.  You could let the EtOH evaporate and see if any residue is left, too. 

[marquis]

Bulk density in polymers is different from normal chemical density.  In bulk density, you are after how much material will fit in a specified volume.  So, for example, you might fill a 100 ml tared graduated cylinder with the PE or PP and weigh it. The result is weight per volume (in this case, g of polymer per 100 ml).

Most polymers, such as PE and PP, come in beads, sometimes with air pockets in the center.  A specific gravity or density doesn't do you much good.  Bulk density gives you a quick idea of how much material will fit in your bulk tanks.