w********h
发帖数: 12367 | 1 polymer gel是一种什么东东？
and hydrogel? |
C***S
发帖数: 175 | 2 a weak cross linked polymer, if the polymer is hydrophilic, it is hydrogel.
Here I mentioned the weak crosslinked polymer, just to differiente them
from the rubber, which as I think is heavily cross-linker.
Weak cross linked polymer mean the system could have the huge capacity
on absorbing solvent, and can endure large shape change.
【在 w********h 的大作中提到】
: polymer gel是一种什么东东？
: and hydrogel?
|
w********h
发帖数: 12367 | 3 great. 看来偶们的基本训练都是不差的。
偶们老板出一本杂志的专辑，邀请了一人些文章，
因为一个审稿人的意见是rejection，他不好意思拒邀稿，
让偶再看看，靠这人也是蛮出名了，名校教授，
连 gel是什么都没弄清，说什么这个gel是fluid-like。
还用rheometer表征这种"gel"，里面G">G'，
这算什么gel阿。
这是我人生中第一次审稿给rejection or major revision。
【在 C***S 的大作中提到】
: a weak cross linked polymer, if the polymer is hydrophilic, it is hydrogel.
: Here I mentioned the weak crosslinked polymer, just to differiente them
: from the rubber, which as I think is heavily cross-linker.
: Weak cross linked polymer mean the system could have the huge capacity
: on absorbing solvent, and can endure large shape change.
|
b**s
发帖数: 589 | 4 “还用rheometer表征这种"gel"，里面G">G'”
这句话没问题呀
我现在做实验的时候也把G">G'作为gel point
表明高分子成为了percolated stress-bearing network
gel和rubber 的区别在於associate和disassociate是不是可逆的
gel 是semi-solid or semi-fluid,
说它fluid-like也没错呀
hydrogel.
【在 w********h 的大作中提到】
: great. 看来偶们的基本训练都是不差的。
: 偶们老板出一本杂志的专辑，邀请了一人些文章，
: 因为一个审稿人的意见是rejection，他不好意思拒邀稿，
: 让偶再看看，靠这人也是蛮出名了，名校教授，
: 连 gel是什么都没弄清，说什么这个gel是fluid-like。
: 还用rheometer表征这种"gel"，里面G">G'，
: 这算什么gel阿。
: 这是我人生中第一次审稿给rejection or major revision。
|
w********h
发帖数: 12367 | 5 hehe, try your gels to see if G" is always larger than G' or not.
【在 b**s 的大作中提到】
: “还用rheometer表征这种"gel"，里面G">G'”
: 这句话没问题呀
: 我现在做实验的时候也把G">G'作为gel point
: 表明高分子成为了percolated stress-bearing network
: gel和rubber 的区别在於associate和disassociate是不是可逆的
: gel 是semi-solid or semi-fluid,
: 说它fluid-like也没错呀
:
: hydrogel.
|
C***S
发帖数: 175 | 6 I guess semi-fluid is quite different from fluid-like.
【在 b**s 的大作中提到】
: “还用rheometer表征这种"gel"，里面G">G'”
: 这句话没问题呀
: 我现在做实验的时候也把G">G'作为gel point
: 表明高分子成为了percolated stress-bearing network
: gel和rubber 的区别在於associate和disassociate是不是可逆的
: gel 是semi-solid or semi-fluid,
: 说它fluid-like也没错呀
:
: hydrogel.
|
r******0
发帖数: 2753 | 7 I think the author was right. Gel could be solid and fluid like; and G">G' is
one
of the widely used criteria for gel point. Wond, if you have any doubt, you
may double check it with Wang, SQ. I belive it was him told me that. hehe...
them
【在 w********h 的大作中提到】
: hehe, try your gels to see if G" is always larger than G' or not.
|
w********h
发帖数: 12367 | 8 the sol--->gel point is from G">G' to G'>G"...
sol gel
there are three regions for ordinary entangled polymers in G',G"---w:
(w is frequency, G'G" storage and loss moduli)
(1) flow region, G"-w^1, G'-w^2, G">G';
(2) plateau region or rubbery region, G"
(3) glassy region or Rouse region. theoretically G'=G"=w^0.5
How a gel only behaves like a fluid in the whole frequency range
in that paper?
gel can be moved by shear-induced collapse
bu
【在 r******0 的大作中提到】
: I think the author was right. Gel could be solid and fluid like; and G">G' is
: one
: of the widely used criteria for gel point. Wond, if you have any doubt, you
: may double check it with Wang, SQ. I belive it was him told me that. hehe...
:
: them
|
w********h
发帖数: 12367 | 9 也许我前面表述不清，gel在一些情况下是可以转换成sol的，
但它在gel的状态的时候如何证明它是gel呢？告诉我是不是G'>G"?
is
capacity
【在 r******0 的大作中提到】
: I think the author was right. Gel could be solid and fluid like; and G">G' is
: one
: of the widely used criteria for gel point. Wond, if you have any doubt, you
: may double check it with Wang, SQ. I belive it was him told me that. hehe...
:
: them
|
z**h
发帖数: 224 | 10 if G''/G' is independent of frequency, that is the gelation point.
you
hehe...
【在 w********h 的大作中提到】
: 也许我前面表述不清，gel在一些情况下是可以转换成sol的，
: 但它在gel的状态的时候如何证明它是gel呢？告诉我是不是G'>G"?
:
: is
: capacity
|
|
|
w********h
发帖数: 12367 | 11 个人感觉这个条件既不充分，也不必要。
倒象是block copolymer disorder to order transition在terminal regime的转折
点。
我们看一个东东是不是gel，首先要看这种weak association是不是足够强壮到出现
G'>G"的plateau regime. 如果作者根本就没有有强有力的证据说明这个gelation，
比如(1) 粘度是不是随温度etc有个sharp的增加？(2) 在某些 frequency region
G'>G". 如果这两个证据都没给，反而告诉我这个gel是fluid-like，我不能接受。
G">G'
】
is
differiente
【在 z**h 的大作中提到】
: if G''/G' is independent of frequency, that is the gelation point.
:
: you
: hehe...
|
c*s
发帖数: 2145 | 12 what journal is this manuscript for?
doubt,
【在 w********h 的大作中提到】
: 个人感觉这个条件既不充分，也不必要。
: 倒象是block copolymer disorder to order transition在terminal regime的转折
: 点。
: 我们看一个东东是不是gel，首先要看这种weak association是不是足够强壮到出现
: G'>G"的plateau regime. 如果作者根本就没有有强有力的证据说明这个gelation，
: 比如(1) 粘度是不是随温度etc有个sharp的增加？(2) 在某些 frequency region
: G'>G". 如果这两个证据都没给，反而告诉我这个gel是fluid-like，我不能接受。
:
: G">G'
: 】
|
w********h
发帖数: 12367 | 13 xixi, this is confidential...
if the major part in a manuscript is wrong,
it is dead for any journals...let alone another part is not systematic, as
another referee comments...
这个故事告诉我们：
（1）约稿应该把自己最好的或比较好的东西拿出来；
（2）约稿也有可能被拒，而且双方更尴尬；
（3）不要以为referee里面没有你suppose不应该出现的expert...
【在 c*s 的大作中提到】
: what journal is this manuscript for?
:
: doubt,
|
c*****e
发帖数: 238 | 14 There is little doubt, if any at all, about the definition of chemical gel,
like rubber.
As for physical gel, no one understands what on earth it is.
Experimentalists tend to use the characteristic dynamic response as an
identification of gelation. This is not quite different from naked eye observation
of the gel phase in the solution.
Generally gel is believed to be an elastic liquid, with solid like behavior at
short time scales, but liquid like in nature. So far there is little satisfactory
d
【在 w********h 的大作中提到】
: polymer gel是一种什么东东？
: and hydrogel?
|
c*****e
发帖数: 238 | 15
This should be correct, otherwise ...
fluid-like is very confusing. there are lots of different fluids, maybe
liquid-like is more common
【在 w********h 的大作中提到】
: the sol--->gel point is from G">G' to G'>G"...
: sol gel
: there are three regions for ordinary entangled polymers in G',G"---w:
: (w is frequency, G'G" storage and loss moduli)
: (1) flow region, G"-w^1, G'-w^2, G">G';
: (2) plateau region or rubbery region, G": (3) glassy region or Rouse region. theoretically G'=G"=w^0.5
: How a gel only behaves like a fluid in the whole frequency range
: in that paper?
: gel can be moved by shear-induced collapse
|
c*****e
发帖数: 238 | 16 I doubt it, both moduli depend on the frequency, and in the gel phase
the dependences are both nontrivial and different: one goes to constant at
large frequency and vanishes at small frequency, the other gradually decreases
at large frequency but remains finite at small frequency.
How can their ratio become independent of frequency?
I am referring to physical gels.
【在 z**h 的大作中提到】
: if G''/G' is independent of frequency, that is the gelation point.
:
: you
: hehe...
|
z**h
发帖数: 224 | 17 at the gelation point, the G' and G" have the same dependence of frequency,
so the ratio is independent of frequency. P344, Polymer physics, Ralph,Colby.
decreases
【在 c*****e 的大作中提到】
: I doubt it, both moduli depend on the frequency, and in the gel phase
: the dependences are both nontrivial and different: one goes to constant at
: large frequency and vanishes at small frequency, the other gradually decreases
: at large frequency but remains finite at small frequency.
: How can their ratio become independent of frequency?
: I am referring to physical gels.
|
w********h
发帖数: 12367 | 18 that one is for unentangled branched polyesters.
I think it is quite different from polymer gel, which is defined very well on
Pages 199-206 in the same book.
That one is Rouse behavior which can be observed in any polymers in Glassy (or
Rouse) regime.
Ralph,Colby.
【在 z**h 的大作中提到】
: at the gelation point, the G' and G" have the same dependence of frequency,
: so the ratio is independent of frequency. P344, Polymer physics, Ralph,Colby.
:
: decreases
|
b**s
发帖数: 589 | 19 Find two definition of gel
1. A gel is a colloidal system with a finite, usually rather small, yield
stress. Materials such as silica gel which have passed a gel stage during
preparation, are improperly called gels.
2. Rheologically, a sample is said to form a gel when it acquires a nonzero
shear modulus
on
(or
frequency,
at
【在 w********h 的大作中提到】
: that one is for unentangled branched polyesters.
: I think it is quite different from polymer gel, which is defined very well on
: Pages 199-206 in the same book.
: That one is Rouse behavior which can be observed in any polymers in Glassy (or
: Rouse) regime.
:
: Ralph,Colby.
|
