f*****n 发帖数: 12 | 1 Someone told me that from TGA curves we can get some information about Tg of
a polymer? Do you have any idea about it?
Thank you very much.
fourgen |
S*****n 发帖数: 6055 | 2 no
of
【在 f*****n 的大作中提到】 : Someone told me that from TGA curves we can get some information about Tg of : a polymer? Do you have any idea about it? : Thank you very much. : fourgen
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r******0 发帖数: 2753 | 3 Who told you that? Maybe s/he was talking about DMA or TMA?
of
【在 f*****n 的大作中提到】 : Someone told me that from TGA curves we can get some information about Tg of : a polymer? Do you have any idea about it? : Thank you very much. : fourgen
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f*****n 发帖数: 12 | 4 Sorry for the late reply.
This is required by my boss.
Now, I found a paper on it. A guy really got Tg from TGA test. I feel it is
very questionalbe. Roughly, his idea is that the evaporating rate of solvent
or small molecules in the polymer will abruptly change at Tg, which will be
reflected from the TGA curve. |
p******e 发帖数: 164 | 5 It is quite questionable because small molecules will change Tg greatly.
You will never know where is Tg in TGA.
is
solvent
be
【在 f*****n 的大作中提到】 : Sorry for the late reply. : This is required by my boss. : Now, I found a paper on it. A guy really got Tg from TGA test. I feel it is : very questionalbe. Roughly, his idea is that the evaporating rate of solvent : or small molecules in the polymer will abruptly change at Tg, which will be : reflected from the TGA curve.
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S*****n 发帖数: 6055 | 6 well, even if this method works, your Tg has to be in the range between RT
and boiling point of your solvent......
is
solvent
be
【在 f*****n 的大作中提到】 : Sorry for the late reply. : This is required by my boss. : Now, I found a paper on it. A guy really got Tg from TGA test. I feel it is : very questionalbe. Roughly, his idea is that the evaporating rate of solvent : or small molecules in the polymer will abruptly change at Tg, which will be : reflected from the TGA curve.
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S*****n 发帖数: 6055 | 7 small molecules can change Tg? they even don't have Tg ah......
【在 p******e 的大作中提到】 : It is quite questionable because small molecules will change Tg greatly. : You will never know where is Tg in TGA. : : is : solvent : be
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p******e 发帖数: 164 | 8 ft...they don't have Tg, they can drop Tg.
you forget plasticization effect?
【在 S*****n 的大作中提到】 : small molecules can change Tg? they even don't have Tg ah......
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f*****n 发帖数: 12 | 9 Solvent surly has a very low Tg. However, if the content of the solvent is
very low, maybe the evaporating rate is reflected on the TGA curves.
The problem about this method or the idea lies 1)if the diffusion
mechanisms of solvent changed at Tg of polymer (lots of results show no
effect at least for water); 2) just as saind the plasticization effect.
Thank your all reply. |
r******0 发帖数: 2753 | 10 Haven't seen this paper. Actually, I think the idea makes some sense if
there were data support it.
You can imagine that TGA measurement started below the Tg of the complex(
polymer/plasticizer). And when T reached the Tg of the pure polymer, there
might be something changed in the complex and evaporation rate changed
suddenlly. Anyway, if the plasticization had not been considered, this paper
was joke for sure.
【在 f*****n 的大作中提到】 : Solvent surly has a very low Tg. However, if the content of the solvent is : very low, maybe the evaporating rate is reflected on the TGA curves. : The problem about this method or the idea lies 1)if the diffusion : mechanisms of solvent changed at Tg of polymer (lots of results show no : effect at least for water); 2) just as saind the plasticization effect. : Thank your all reply.
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