[majortom_thecat]

Hello! 

I'm new here.  I'm trying to make a soft fabric out of HDPE grocery bags.  I used a hot iron to fuse four layers together and ended up with a material that is pretty much the same thing as Tyvek.  It's very stiff.  I put it in a pillow case with a dryer ball and let it hang out in the dryer for several loads but it didn't soften up much.  I got better results crumpling it in my hands, but that much crumpling was getting tedious and time consuming. 

I thought about using lye to try to soften it, but a google search revealed that HDPE is actually recommended for storing lye. 

I folded the sheet and put it into a peanut butter jar, filled the jar with acetone, and left it to soak for 12 hours.  It seems maybe a little more flexible, but it still has  long way to go.

I think it must be possible to soften this stuff because I have a HDPE shower curtain and it is very, very soft.

Doe anyone have any other ideas I could try?

Thanks so much!

[typhoon2028]

Hi

HDPE is stiff by nature.  Stiffness does not always equate to a "feel of softness."  Search haptics.  I work for a company that manufactures polyolefin foams.  We come across the stiffness/softness issue frequently.

Your shower curtain maybe processed in a way to make feel soft to the touch.  Also make sure the shower curtain is 100% HDPE.

What were you trying to do with the acetone?  You could try to partially dissolve the HDPE with hot toluene or naptha.