How safe is vinyl for other plastics? - Page 1
Forum section: electronics / general

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 03, 2021, 07:41:38 pm
content: I bought a bunch of resealable pouches and when I got them they smelled of vinyl. I didn't think vinyl was still used these days.Storing old junk like 30 year old disk drives, etc, often I notice burn marks on the plastic cases which turn out to be caused by a chemical reaction between whatever plastic cables are made from and whatever the case is made from.I guess cases are usually made from ABS.Is storing stuff inside vinyl bags safe long-term?I also plan to keep other junk organized in pouches.What is a better material for storing things long term?

author: jpanhalt
author_rank: Super Contributor
timestamp: October 03, 2021, 08:21:43 pm
content: Do you mean PVC?https://en.wikipedia.org/wiki/Vinyl_groupYes, I would be concerned about "vinyl" goo transferring to anything valuable.

author: rdl
author_rank: Super Contributor
timestamp: October 04, 2021, 01:38:51 am
content: It's called plasticizer migration. It's a fairly complex phenomenon. To be completely safe you'd have to avoid bags made with any kind of plasticizer.

author: james_s
author_rank: Super Contributor
timestamp: October 04, 2021, 01:44:23 am
content: I've run into that a few times with power cords wrapped around thing. I also had it happen when I left rolls of two different types of tape stacked on a shelf. I don't remember what one of them was but the one that melted was that thin yellow tape often used to cover transformer windings. The spots where the other tape rested on it fused together into sticky yellow blobs. It's a really annoying phenomenon and I've never seen a list of material compatibility.

author: amyk
author_rank: Super Contributor
timestamp: October 04, 2021, 02:37:23 am
content: Quote from: rdl on October 04, 2021, 01:38:51 amI believe only polyethylene doesn't have plasticisers; fortunately, regular plastic bags are polyethylene.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 04, 2021, 03:22:03 am
content: That's what I was afraid of. Oh well it's unavoidable. They sellhemplinen bags with drawstrings on alix but they are too small.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 04, 2021, 05:12:35 am
content: Current plastic bad are polyethylene, and without plasticisers. PVC bags were more a thing of the 1970s.Most new plastic parts are marked and many boxes are now more PP or PE which are no problem.PVC is mainly found with cable isolation, but even there newer alternatives are coming up. However these can also include plasticisers.

author: rdl
author_rank: Super Contributor
timestamp: October 04, 2021, 01:45:23 pm
content: As others have said, just buy some PE (polyethylene) type bags. Polyethylene does not require plasticizer. Polypropylene (PP) would be okay also, though I don't think it's commonly used for bags. Another alternative might be those silvery metallized type anti-static bags. Pretty sure most of those are some kind of Mylar/polyester which also needs no plasticizer.

author: tooki
author_rank: Super Contributor
timestamp: October 04, 2021, 04:42:07 pm
content: Quote from: amyk on October 04, 2021, 02:37:23 amBoth polyethylene and PET don’t use plasticizers, typically.Though I did stumble across this book chapter that dives deep into the compatibility of particular plasticizers with particular polymers, attached for whoever’s curious.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 05, 2021, 12:19:54 am
content: Quote from: tooki on October 04, 2021, 04:42:07 pmclick -> save asthanks!