Power cords turning oily.

[MadMan]

Old fashioned plastics breaking down. Ever see an old car with a sticky foggy windshield? First guess is it's driven by a heavy smoker. If not, it's probably the plasticizer evaporating out of the dash board under the hot sunlight. It is what it is, unfortunately. Polymers have come a long way.

[ppppenguin]

Nasty goo or oiliness is usually the plasticisers from PVC. Sometimes green goo forms inside cables and works its way out at the terminals. Presumably a reaction with copper.

Never leave PVC in contact with polystyrene. The PVC will deplasticise and the polystyrene will dissolve. Expanded polystyrene will suffer very badly. Hard polystyrene, such as used in many sets of small drawers, will be marked.

As others have said, PVC cable can also mark other materials, such as some oiled or lacquered surfaces.

It can be a safety hazard where PVC insulated house wiring is in contact with expanded polystyrene thermal insulation.

Old PVC insulation may not be in the same rotten class as old rubber but sometimes it comes close.

[crt89]

Originally Posted by ppppenguin

Nasty goo or oiliness is usually the plasticisers from PVC. Sometimes green goo forms inside cables and works its way out at the terminals. Presumably a reaction with copper.

I've had that green goo appear on the prongs of a plug on an old Hoover vacuum cleaner. Never seen it elsewhere. Clean it off and it comes back later.

I remember reading a manual for an appliance (I forget what, exactly) that stated the cord shouldn't be wrapped around the unit while storing, because it could leave marks. Only time I ever heard of that.

[vortalexfan]

I've worked on many old radios that had the old plastic and or rubber power cords from the 1950s that had green goo leaked out of the prongs of the plug ends and even original cords on some of the old floor lamps from the 1940s.

I also have a mid 1950s Westinghouse Radio that the walnut Bakelite Cabinet and Black Bakelite Chassis and original rubber cord are in mint condition.

But the tuning knob which is supposed to be see through plastic (as the stations you are tuning in are seen through the knob) is all fogged up because of the plastic oxidizing.

The fog on the plastic tuning knob will clean off with regular soap and water, which makes the knob see through again but then about 2 or 3 months later the fog on the tuning knob is back.