w******r
发帖数: 43 | 1 I have this blend. I want to get the PB-PEO diblock.
I tried the toluene/methonal system. It did not work.
The old way is using hexane dissolve PB and seperate the diblock
by centrifuge. I donot like this method, because it is time consuming.
Does anybody has any new ideas?
We can discuss it.
Thanks |
|
w********h
发帖数: 12367 | 2 Mesophases of Diblock Copolymers in Solution
Collaborators – Prof. R.A. Register, Chiajen Lai
Funding - National Science Foundation (Princeton Center for Complex
Materials)
Amphiphiles, such as surfactants and block copolymers, spontaneously
self-assemble in order to minimize interactions between their incompatible
components. In the bulk or concentrated solutions highly regular structures
with periodicity in the nanometer range emerge, according to principles that
are reasonably well-defined f |
|
b**s
发帖数: 589 | 3 A novel hydrogel formed from amphiphilic diblock copolypeptides could have
potential uses in biomedical applications. Scientists at the University of
California, Santa Barbara and the University of Delaware found that a small
amount of a diblock copolypeptide amphiphile, when added to water, formed a
network of polymer chains or hydrogel [ Nature (2002) 417, 424].
Amphiphiles have hydrophobic and hydrophilic sections, but most diblock
copolymer amphiphiles assemble into vesicles in water, |
|
b**s
发帖数: 589 | 4 首先要搞清一个概念：你说的是通常意义的multiblock
AAABBBBBAAAAABBBBAAAAAABBBBBBBAAAAAABBBBBBBBBBBBAAAAAAAAA
还是diblock,
AAAAAAAAAAAAAAAAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
还是Triblock
AAAAAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBAAAAAAAAAAAAAAAAAAAAAAA
一般说嵌段都是指先加一种单体，聚一段时间再加另一种单体的这种diblock
，Triblock的结构
不过看来你指的是第一种情况，这很正常，这要涉及“竞聚率”的概念，如还不明白
，请参考复旦版（高分子化学）
你是要什么结构先？
－－－－－－－－－－－－－－
如有用，请wonderlich转到chemistry版
－－－－－－－－－－－－－－ |
|
y****u
发帖数: 50 | 5 I am a little puzzled. what is your question again?
If your concern is about the (number) average molecular weight of PMMA in
PSt-PMMA diblock copolymer: First get wt% of PMMA (by NMR or whatever), then
get Mn of diblock from GPC. |
|
c*****e
发帖数: 238 | 6 For asymmetric diblock copolymer melts, the phase transition point from
mean field approximation is not \chi*N>10.495, but is higher.
The 10.495 limit is only at the critical point which is for symmetric diblock
copolymers. |
|
A********e
发帖数: 354 | 7 【 以下文字转载自 Biology 讨论区 】
发信人: albertsmwk (.)(.), 信区: Biology
标 题: 第一批“青年千人计划”生物类@publication列表@
发信站: BBS 未名空间站 (Thu Aug 18 15:04:16 2011, 美东)
花了一个小时，深深的鄙视一下自己的无聊行径！！
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branche... 阅读全帖 |
|
p*******g
发帖数: 2976 | 8 【 以下文字转载自 Biology 讨论区 】
发信人: albertsmwk (.)(.), 信区: Biology
标 题: 第一批“青年千人计划”生物类@publication列表@
发信站: BBS 未名空间站 (Thu Aug 18 15:04:16 2011, 美东)
花了一个小时，深深的鄙视一下自己的无聊行径！！
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branche... 阅读全帖 |
|
O***n
发帖数: 13127 | 9 【 以下文字转载自 Biology 讨论区 】
发信人: albertsmwk (.)(.), 信区: Biology
标 题: 第一批“青年千人计划”生物类@publication列表@
发信站: BBS 未名空间站 (Thu Aug 18 15:04:16 2011, 美东)
花了一个小时，深深的鄙视一下自己的无聊行径！！
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branche... 阅读全帖 |
|
a********k
发帖数: 2273 | 10 花了一个小时，深深的鄙视一下自己的无聊行径！！
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branches in lamellipodia. Cell. 2008 Sep
5;134(5):828-42. PubMed PMID: 18775315; PubMed Central PMCID: PMC2570342.
Cai L, Makhov AM, Bear JE. F-actin... 阅读全帖 |
|
b**********e
发帖数: 531 | 11 伸绿卡急用，哪位好心人帮帮忙
Cao, W.; Sun, L.; Rong, L.; Hsiao, B.S.; Zhu, L., Chirality effect on
interaction parameters in poly(ethylene-co-1-butene)-b-polylactide diblock
copolymers. PMSE Preprints 2008, 99 378-380.
Zhu, L.; Sun, L.; Miao, J.; Hsiao, B. S.; Avila-Orta, C. A.; Sics, I.
Structure and morphology of crystalline polymer/clay nanocomposites.
Proc. NATAS Annu. Conf. Thermal Anal. Appl. 2004, 32nd, 101.10.727/1-
101.10.727/5.
Zhu, L.; Sun, L.; Ge, Q.; Quirk, R. P.; Hsiao, B. S.; Avila-Orta, C |
|
|
x********e
发帖数: 1064 | 13 Polyisobutylene-block-poly(methacrylic acid) Diblock Copolymers: Self-
Assembly in Aqueous Media
Langmuir, 2007, 23 (26), pp 12864–12874
Please sent to t*********[email protected]
Thanks |
|
|
f******n
发帖数: 137 | 15 “Synthesis of Polymethacrylate Derivatives Containing Conducting
Diphenyldithiophene as Pendant Side Chain”Reichmanis, Elsa; Polymer
Preprints, ACS Fall Conference, 2011
Alternating and Diblock Donor–Acceptor Conjugated Polymers Based on
Diindeno[1,2-b:2′,1′-d]thiophene Structure: Synthesis, Characterization,
and Photovoltaic Applications, Volume 5, Issue 12, pages 2483–2492,
December 3, 2010
http://onlinelibrary.wiley.com/doi/10.1002/asia.201000506/abstr |
|
b**s
发帖数: 589 | 16 如果不是diblock or triblock型
C13 NMR 可以很容易看出来 |
|
w*z
发帖数: 35 | 17 the question is how to tell something is a diblock copolymer, or a mixture of
two homoplymers. any characteration methods? |
|
z***x
发帖数: 9 | 18 soxlet extraction may work. |
|
y****u
发帖数: 50 | 19
if you know Mn, you will get the number of repeating units. and vice versa.
true. but nobody is talking about Mw.
we don't need this for a solution.
it seems to be diblock. so only one PMMA segments in a copolymer chain. but
your calculation is right: 7 MMA repeating units (number average) in a
copolymer chain. |
|
y****u
发帖数: 50 | 20 basically the original question was about wt% or mol%. obviously it is wrong
to use mol%.
yes, we can. once we know the Mn of diblock and wt% of MMA, the second monomer
doesn't matter for the answer.
but
My understanding: "segment"="block". |
|
y****u
发帖数: 50 | 21 It is not amphiphilic...and both segments are glassy...just to demonstrate
synthetic skills?
actually I am about to prepare proposal...and I can propose a whole lot of
block copolymers. but I don't have much knowledge of their possible
applications. wish to get some ideas. thanks. |
|
z**h
发帖数: 224 | 22 diblock copolymer phase separation happens when chiN>10.5 from mean filed
theory.
structure
的block的平均长度决定,在这种近似下每一种segment的block的等效长度大概是N^(1/2) |
|
c*****e
发帖数: 238 | 23 Forgot to mention that this criterion is for symmetric diblock copolymers.. |
|
z**h
发帖数: 224 | 24 no, it is not only for symmetric. for symmetric diblock copolymer, lamellae
morphology will form after phase separation. with the change of volume
fraction of two blocks, the morphology will change also.
filed
的block的平均长度决定,在这种近似下每一种segment的block的等效长度大概是N^(1/2) |
|
z**h
发帖数: 224 | 25 yes. for asymmetric it is bigger than 10.495
diblock
lamellae
copolymers..
的block的平均长度决定,在这种近似下每一种segment的block的等效长度大概是N^(1/2) |
|
c****n
发帖数: 134 | 26 not PIP but PIB.
since the diblock copolymer is soluble in DMSO,
I have checked the structural integrity by NMR.
and----the homoPVA prepared in similar way was soluble in water.
is |
|
c***r
发帖数: 4631 | 27 Do you ever think grow polymer-lithium battery from diblock or tri-block
copolymer directly on the IC? Or call it "Nano-battery"?
in
recently
with |
|
w******r
发帖数: 43 | 28 what is your means about phase diagram?
Block copolyme can form different morphologies in dilute solutions.
With increase of concentration, the micelle solution could be BCC, FCC
structure. TPL has some papers about the characterization and kinetic
transition between BCC<>FCC.
Bates reported various micelle morphlogoies formed
from PBD-PEO diblock copolymers. They did a lot of cryoTEM and got very nice
images.
(1) Jain, S.; Bates, F. S. Science 2003, 300, 460.
(2) Won, Y.-Y.; Brannan, A. K.; Dav |
|
z**h
发帖数: 224 | 29 polymers.
any connection between spinodal decompostion and nanophase seperation of
diblock copolymers? |
|
c*s
发帖数: 2145 | 30 diagram of diblock copolymer? saw it tens of times, when I need this, I can
not find it, ft |
|
h***s
发帖数: 111 | 31 I just made SBS triblock by coupling of S-x and y-B-y. How can I prove that it
is a triblock insted of SB diblock? PB has a PDI of 2. It is hard to tell by
GPC.
Thanks! |
|
D***e
发帖数: 435 | 32 为什么要研究morphology?有什么重要意义
有什么paper 可以推荐吗？ 关于diblock copolymer morphology的意义
在在做这个drug delivery的应用。
是是新手。
请教大家。 |
|
D***e
发帖数: 435 | 33 要把diblock copolymer PB-PEO的PB block cross link, K2S2O8做 initiator
看到文献上说用argon protection.请问可以换做nitrogen protection吗？
实验室没有argon，也不知道该怎么买？是不是跟氮气一样买？
问题比较外行。从来没搞过polymer 的反应，没有经验
请大家指教，谢谢了。 |
|
z**h
发帖数: 224 | 34 为什么在AB diblock copolymer phase diagram 上没有这么一个 disordered
microphase separated regime, 而只有 disorder-order line?
microphase |
|
|
S*****n
发帖数: 6055 | 36 如果认为TGA的两个平台是由于A－A和B－B解离能不同造成的
那么diblock和triblock的平台应该在相同的温度出现，呵呵 |
|
y***e
发帖数: 6082 | 37 没啥意思啊，搞来搞去最多macro，大牛们都喜欢diblock或者triblock然后自组装成千奇
百怪的东西，ibm现在搞得太火了
做block copolymer的那些组，大多数都做阴离子的吧，不过不怎么单独发合成的文章，
呵呵。 |
|
l***i
发帖数: 34 | 38 Volume 71, 2006
Jun-Hua Wan, Jia-Chun Feng, Gui-An Wen, Wei Wei,
Qu-Li Fan, Chuan-Ming Wang, Hong-Yu Wang, Rui Zhu,
Xiang-Dong Yuan, Chun-Hui Huang, and Wei Huang.* Effective
Tuning of HOMO and LUMO Energy Levels by p-n Diblock and
Triblock Oligomer Approaches.
Pages 2565-2571. This manuscript was withdrawn from
publication by The Journal of Organic Chemistry (JOC) Editorin-
Chief. The basis for the withdrawal was a violation of the
Ethical Guidelines to Publication of Chemical Research of the
A |
|
s****e
发帖数: 2934 | 39 质量很差，比如diblock copolymer里面有很多homopolymer等等，大家有好一点的地方
推荐吗？ |
|
s****e
发帖数: 2934 | 40 ☆─────────────────────────────────────☆
cds (红毛呼呼猪) 于 (Sun Oct 1 23:40:38 2006) 提到:
thanks a lot. BUt my case is kinda special. it is PEG-PtBA, as u know, PtBA
can be dissolved in almost all solvents except water. therefore, the
solubility property of the block polymer is quite similar to homopolymer.
what I am trying to do is to precipitate PEG in MeOH using ether, while
keeping the block polymer micelles in MeOH. This looks viable but I am not
sure this is the best combination or not in |
|
s****e
发帖数: 2934 | 41 【 以下文字转载自 NanoST 讨论区 】
发信人: maodouzi (毛豆子), 信区: NanoST
标 题: Advanced materials上最近几篇太阳能电池文章
发信站: BBS 未名空间站 (Wed Jun 6 10:33:41 2007), 转信
１.Amphiphilic Diblock Copolymer Compatibilizers and Their Effect on the
Morphology and Performance of Polythiophene:Fullerene Solar Cells**
２. Design Rules for Donors in Bulk-Heterojunction Solar Cells—Towards 10
% Energy-Conversion Efficiency**
By Markus C. Scharber,* David Mühlbacher, Markus Koppe, Patrick Denk,
Christoph Waldauf,
Alan J. Heeger, and Christo |
|
s*******b
发帖数: 8 | 42 常规的就这两种：
1）disorder structure factor S(q)
fit to Leibler's RPA expression
2）order-disorder transition temperature for symmetric diblock with varying
chain lengths
use \chi_{ODT} N = 10.5 of Leibler's result
两条都参见你前前面帖子问过的 Leibler 的经典文献。实验方面参考 Bates（
Minnesota）和 Balsara
（Berkeley）的相关文献。
评论：没有任何一种测量方法是可靠的。但我更推荐第一种（ODT 对涨落更敏感）。
原因：（1）这两个办法都基于平均场理论，而对有限长链，涨落效应非常大，并且尚
无自恰的理论修正；Helfand
－Fredrickson 的理论有意思，但忽略了重要的因素，不可过于依赖；（2）按照现有
的理论得到chi 的数值对嵌段
共聚物体系和同聚物体系非常不一致，概念上是个漏洞，还没有解释。大家一直在用，
只是因为容 |
|
S*****n
发帖数: 6055 | 43 各位老大，请教个问题
俺想做个PS-PBD的胶束，选择用hexane做溶剂，希望能弄点胶束出来玩。现在尝试了两
种block copolymer，一个diblock，一个SBS，其中PS的含量都在20-25%，但是发现，
polymer都无法溶解，只能溶胀。。。
想请教一下，如何能实现我的目标呢？
现在有两个想法，一个是继续降低PS的含量，不知道有没有可能溶解？hexane应该是PS
的不良溶剂，但是可以溶解PBD
再一个是再找个PS的良溶剂，跟hexane混起来溶解copolymer，然后把另外一种溶剂除
掉，看看能不能得到PS-PBD的胶束。但是这另外一种溶剂选什么合适，还在琢磨。。。
三年来，除了这个版面，没有看过跟polymer有关的任何东西，都快忘光了。。。问题
比较弱，大家多排砖，多谢！ |
|
s****e
发帖数: 2934 | 44 这个PS-PBD的micelle难道没有文献吗？先查文献用什么样的分子量和怎么用溶剂。PBD貌似会交联，注意保存。形成micelle貌似要好多天。还要不停的搅，对了，还有浓度也是个问题，你看到溶胀是不是就是溶质太多了？
Solution Properties of Diblock Copolymers of Polystyrene-block-polybutadiene
这个文章有用吗
dibutyl phthalate是PS的选择性溶剂，把DBP和benzene混起来再把benzene挥发就得到micelle了。
PS |
|
|
b**********e
发帖数: 531 | 46 伸绿卡急用，哪位好心人帮帮忙
Cao, W.; Sun, L.; Rong, L.; Hsiao, B.S.; Zhu, L., Chirality effect on
interaction parameters in poly(ethylene-co-1-butene)-b-polylactide diblock
copolymers. PMSE Preprints 2008, 99 378-380.
Zhu, L.; Sun, L.; Miao, J.; Hsiao, B. S.; Avila-Orta, C. A.; Sics, I.
Structure and morphology of crystalline polymer/clay nanocomposites.
Proc. NATAS Annu. Conf. Thermal Anal. Appl. 2004, 32nd, 101.10.727/1-
101.10.727/5.
Zhu, L.; Sun, L.; Ge, Q.; Quirk, R. P.; Hsiao, B. S.; Avila-Orta, C |
|
l**********g
发帖数: 55 | 47 想买双亲diblock，端基是带胺基或者酸的那种，可以coupling到别的上面去，请问什
么公司有呢？谢谢各位了！ |
|
p******4
发帖数: 38 | 48 I am using AFM to demonstrate self assembly of well-defined diblock
copolymers, but so far haven't got any good images. The block copolymer has
one polar and one nonpolar segments, so it is supposed to show morphology
not so difficult. The copolymer was spin coated on glass slides (which have
been cleaned in Piranha solution). My questions are
1. Do the glass substrates need to be coated with some polymers? In some
references it mentioned that the glass slides were coated with pure
polystyrene t |
|
g***e
发帖数: 584 | 49 来自主题: Macromolecules版 - 求助文献 题目是：SYNTHESIS AND CHARACTERIZATION OF PS-PI AND PS-PBD RANDOM COPOLYMERS
AND
RANDOM-DIBLOCK COPOLYMERS VIA ANIONIC POLYMERIZATIONS
作者：SMITH SD, ASHRAF A, CLARSON SJ
来源出版物: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 卷: 206
页: 387-POLY
子辑: Part 2 出版年: AUG 22 1993
非常感谢！ |
|
h****z
发帖数: 1996 | 50 我做过一个PLA为主的diblock 1000-2000 也没有得到固体过 |
|
