z***x
发帖数: 9 | 1 I have made a polyethylene. GPC shows two different peaks, each peak has the
PDI of around 1.1. and the first peak shows about two times molecular weight
of the second peak.
Is there any simple way to separate these two polymers.
Thanks a lot |
t*****y
发帖数: 30 | 2 use fractionation?
【在 z***x 的大作中提到】
: I have made a polyethylene. GPC shows two different peaks, each peak has the
: PDI of around 1.1. and the first peak shows about two times molecular weight
: of the second peak.
: Is there any simple way to separate these two polymers.
: Thanks a lot
|
z***x
发帖数: 9 | 3 how to do it?
Thanks!
the
weight
【在 t*****y 的大作中提到】
: use fractionation?
|
w********h
发帖数: 12367 | 4 似乎是合成里面的基本方法吧，估计搞合成的人都做过。
以前我们组里也分离纯制一些单分散的聚合物。
【在 z***x 的大作中提到】
: how to do it?
: Thanks!
:
: the
: weight
|
d***l
发帖数: 48 | 5 soxlet extraction?
【在 z***x 的大作中提到】
: I have made a polyethylene. GPC shows two different peaks, each peak has the
: PDI of around 1.1. and the first peak shows about two times molecular weight
: of the second peak.
: Is there any simple way to separate these two polymers.
: Thanks a lot
|
b********t
发帖数: 992 | 6 你是要怎么分离，是POLYMER还是只是GPC上分，如果是GPC，操作很简单，当高分子量的
峰出来时候，这一分子量的分子链实际上已经从某一根COLUMN中出来了，而小分子量在CO
LUMN中停留的时间比较长，还不会出来，截取这一段的回收液重新做GPC就只会有第一个
峰。
如果是分离不同组份的POLYMER，你要找到合适的溶剂来溶解某一组份而保证其他的不溶
才行，溶剂的选择恐怕要考虑溶解度参数，来寻找合适的溶剂或者混合溶剂
【在 z***x 的大作中提到】
: I have made a polyethylene. GPC shows two different peaks, each peak has the
: PDI of around 1.1. and the first peak shows about two times molecular weight
: of the second peak.
: Is there any simple way to separate these two polymers.
: Thanks a lot
|
w********h
发帖数: 12367 | 7 用GPC分离得多少时间啊？
的
CO
个
溶
the
weight
【在 b********t 的大作中提到】
: 你是要怎么分离，是POLYMER还是只是GPC上分，如果是GPC，操作很简单，当高分子量的
: 峰出来时候，这一分子量的分子链实际上已经从某一根COLUMN中出来了，而小分子量在CO
: LUMN中停留的时间比较长，还不会出来，截取这一段的回收液重新做GPC就只会有第一个
: 峰。
: 如果是分离不同组份的POLYMER，你要找到合适的溶剂来溶解某一组份而保证其他的不溶
: 才行，溶剂的选择恐怕要考虑溶解度参数，来寻找合适的溶剂或者混合溶剂
|
z***x
发帖数: 9 | 8 I need the polymer for NMR analysis.
and we don't have recycle GPC in my lab. //sigh.
and the polyethylene I made is perfect linear and very low molecule weight.
one is around 600(Mn), the other is around 2000 (Mn).
I think the fractionation by suitable solvent will be the easist way to carry
out. then the problem will be what kind of solvent and temperature. I wonder
if anyone can give me some hints.
Thanks
的
CO
个
溶
the
weight
【在 b********t 的大作中提到】
: 你是要怎么分离，是POLYMER还是只是GPC上分，如果是GPC，操作很简单，当高分子量的
: 峰出来时候，这一分子量的分子链实际上已经从某一根COLUMN中出来了，而小分子量在CO
: LUMN中停留的时间比较长，还不会出来，截取这一段的回收液重新做GPC就只会有第一个
: 峰。
: 如果是分离不同组份的POLYMER，你要找到合适的溶剂来溶解某一组份而保证其他的不溶
: 才行，溶剂的选择恐怕要考虑溶解度参数，来寻找合适的溶剂或者混合溶剂
|
d***l
发帖数: 48 | 9 by polarity.
lower MW, more polar. For example, MeOH, Hexane, CHCl3..........
carry
量
在
一
不
【在 z***x 的大作中提到】
: I need the polymer for NMR analysis.
: and we don't have recycle GPC in my lab. //sigh.
: and the polyethylene I made is perfect linear and very low molecule weight.
: one is around 600(Mn), the other is around 2000 (Mn).
: I think the fractionation by suitable solvent will be the easist way to carry
: out. then the problem will be what kind of solvent and temperature. I wonder
: if anyone can give me some hints.
: Thanks
:
: 的
|
b********t
发帖数: 992 | 10
u need to do it yourself,just to collect the solvent from the
column and then inject it again.
the Mn is too low,maybe u need to find some weak slovent which wont dissolve
your sample at room temperature, hopefully, when heating a little bit, it will
dissolve the 600
carry
量
在
一
不
【在 z***x 的大作中提到】
: I need the polymer for NMR analysis.
: and we don't have recycle GPC in my lab. //sigh.
: and the polyethylene I made is perfect linear and very low molecule weight.
: one is around 600(Mn), the other is around 2000 (Mn).
: I think the fractionation by suitable solvent will be the easist way to carry
: out. then the problem will be what kind of solvent and temperature. I wonder
: if anyone can give me some hints.
: Thanks
:
: 的
|
