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Linen sheet vs polyester blanket

  1. Jan 1, 2009 #1
    Why is a linen sheet much colder than the polyester blanket (not cold at all) when I return at night? Could it be that the polyester blanket still kept the heat since morning? (Neither was covered.)

    Is polyester "plastic"?
  2. jcsd
  3. Jan 1, 2009 #2


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    The insulation comes from trapping air. Your linen sheet is thin and doesn't trap much air so has a poor insulation or higher conductivity if you prefer. So it allows more heat to escape form your body. The thick polyester blanket traps a lot more air and so is a poorer conductor - the heat stays near your body and it feels warmer.
    It isn't really a property of the polyester, a wool blanket is a good insulator and down is about the best you can get.

    Yes polyester is a plastic
  4. Jan 1, 2009 #3
    So the blanket is not warm because it traps heat since the morning, but that when I lay down at night, it instantly prevents my heat from escaping such that I don't feel cold (as in heat escaping)?

    Ironically, I have a down blanket, but it had a linen cover. When I first touch it at night, the down blanket with cover was what was cold, while the polyester blanket was not cold.
  5. Jan 1, 2009 #4


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    Correct the blanket doesn't store very much heat - it just reduces the rate of heat loss.
    The linen cover of the down blanket will feel cold - but the down will keep you warm.

    It's like touching a piece of metal and plastic outside in winter, they are both at the same temperature but the metal conducts heat away from your body faster and so feels colder.
  6. Jan 2, 2009 #5

    Ranger Mike

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    trivia- a wool blanket is the only material known (IMHO) that will keep you warm, when totally soaked. Cotton, man made fiber..etc..no good.
    if you know of something new on the scene..pls let me know.
  7. May 3, 2009 #6
    I am not very strong physically but between polyester and feather of goose d, in the goose down blanket is much warmer than the ployestere plastic and more environmentally safe.
    I have bought a blanket down in polyester and can say that it really retain heat report a feather of goosehttp://www.down-bedding.us/Feather-bed-king.htm
    see you later
  8. May 3, 2009 #7
  9. May 4, 2009 #8

    Andy Resnick

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    Are they in fact different temperatures, or does one "feel" warmer than the other? The latter is explained due a difference in thermal transfer between your body and the object, while the former may be explained due to a difference in air permeability (if I am understanding the context of the question).

    Polyester is a synthetic polymer and can be considered a plastic derived from petrochemicals.
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