Link between MW and porosity PE

[lelava]

Hi. Could someone tell me the link between porosity and molecular weight for HDPE and UHMWPE?
Thanks, help is appreciated.

 

[patprimmer]

Porosity and Molecular weight are not related.

density of PE and molecular weight are not related.

Density and porosity are related, if by porosity you mean barrier properties. For a specific polymer type, all other factors being equal, density is directly related to crystallinity, and barrier properties are directly related to crystallinity.

Regards

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[lelava]

Hi. Thanks. With the sample of UHMWPE received to design a porous sparger, they seemed to imply a connection, saying that was why there was a certain amount of porosity, so I wanted to look it up.
Thanks for help.

 

[patprimmer]

They may have been unable to obtain a fully melted and fused moulding due to the high viscosity of the melt restricting flow, which is an indirect effect of high molecular weight.

Sufficient time, pressure and heat should overcome the problem

Regards

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[Pud]

Hi,

It may be sintered form of UHWPE which would imply there may be porosity.

Rgds


Harry

 

[plastx]

I'm familiar with porous PTFE being used as spargers so I believe you are looking for controlled porosity. I haven't used UHMWPE as a sparger but with PTFE there are several methods to obtain the correct porosity by mixing different materials which have different MW to obtain a targeted porous structure.

Mike

 

[lelava]

Hi. Thanks all for your help. We got the first sample in today, so hope all goes well.
Cheers