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chenluyi0502

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5楼: Originally posted by aircraftvip at 2013-01-13 20:08:40
灯的功率应该已经足够了,但高压汞灯一般会产生大量的热,并因此会导致你体系中水分的大量蒸发。如果有点光源的话建议用点光源,如Omnicure S2000.

总体来说,你需要考虑:
1, 聚合效率:足够的引发剂浓度+足 ...

引发剂浓度是按照龚教授的研究中给出的定量的
光强也是我正在考虑的问题,请问有什么比较方便的方法可以测定光强度吗?
尽量减少样品与空气的接触这点我也有考虑,是不是需要用一个容器把样品装起来里面用惰性气体保护住比较好?除了石英玻璃器皿还有没其他比较廉价的选择呢?
您提到的尽量薄的样品厚度,这个,怎么说呢,龚教授的聚合方法是两步法,也就是第一网络的凝胶在第二网络中溶胀,那么第一网络做的薄,但是溶胀了以后也会变得很厚,这个该怎么办?您说两面都照是指先照第一面,再照第二面这样?

然后,您说减少紫外灯放热导致的水分蒸发,这个也是我一开始就在纠结的问题,是这样的,我这边没人做紫外光固化,所以一开始我不知道该如何判断这个光照反应什么时候算聚合完全,所以我一开始就试反应时间,而我把模具中凝胶表面无水分作为固化完全的标准,这样是不是错的?应该把什么作为固化完全的标准?

至于a-酮戊二酸……我所能查到的都是用作生物化学试剂,或者是食品添加剂,有些地方有说这个酮戊二酸可以作为有机合成中间体,应该是指作为引发剂吧,龚教授的论文中写到的就是initiator,2-oxoglutaric acid,至于它的引发机理我也不是很懂。

请您帮帮我,您在这方面应该比较有见解,学弟我不胜感激!
11楼2013-01-14 00:34:22
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chenluyi0502

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6楼: Originally posted by hummerrr at 2013-01-13 21:14:04
加油

谢谢~
12楼2013-01-14 00:34:52
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aircraftvip

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11楼: Originally posted by chenluyi0502 at 2013-01-14 00:34:22
引发剂浓度是按照龚教授的研究中给出的定量的
光强也是我正在考虑的问题,请问有什么比较方便的方法可以测定光强度吗?
尽量减少样品与空气的接触这点我也有考虑,是不是需要用一个容器把样品装起来里面用惰性气 ...

你能把你参照的原文献的链接发过来吗
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13楼2013-01-14 04:49:32
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红舟流星

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黄酮: 金币+1, 欢迎来生物材料回帖交流 2013-01-15 09:33:33
引用回帖:
11楼: Originally posted by chenluyi0502 at 2013-01-14 00:34:22
引发剂浓度是按照龚教授的研究中给出的定量的
光强也是我正在考虑的问题,请问有什么比较方便的方法可以测定光强度吗?
尽量减少样品与空气的接触这点我也有考虑,是不是需要用一个容器把样品装起来里面用惰性气 ...

有专门测光强的测量器的,放置于样品同一高度。
反应动力学可以通过实时红外或者P-DSC来做。
红楼一梦终难寻扁舟载酒且慢行落花流水依惜别月伴明星照前路
14楼2013-01-14 10:32:29
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chenluyi0502

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13楼: Originally posted by aircraftvip at 2013-01-14 04:49:32
你能把你参照的原文献的链接发过来吗...

呃~源链接我找不到了~因为是已经下载了的~我发在华为网盘上~这是外链:http://dl.vmall.com/c0wbddba69
你看看能不能下载~
15楼2013-01-14 14:13:55
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aircraftvip

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chenluyi0502: 金币+10, ★★★很有帮助 2013-01-14 23:37:37
黄酮: 金币+1, 欢迎来生物材料回帖交流 2013-01-15 09:35:13
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14楼: Originally posted by 红舟流星 at 2013-01-14 10:32:29
有专门测光强的测量器的,放置于样品同一高度。
反应动力学可以通过实时红外或者P-DSC来做。...

Unfortunately, real time-FTIR or Photo-DSC are only applicable to samples that do not contain water.

To monitor the curing-kinetics of hydrogels, in-situ photo-rhelogy is the most promising technique in which the principle is gel's elastic modulus depends on the crosslinking density.  Photo-rheometry enables the real-time measurement of both G' and G'' (storage and loss modulus) of the sample. From the curve, you could see when the gel reaches a G' plateau, thus you know whether the curing is done.  In addition, gel point could be easily induced  from the plotted curves.  

Since hydrogels' mechanical properties largely depends on the water content, you'd better not dry your hydrogel out and use this as a sign for full-conversion.

To get general approaches on how to measure hydrogels' mechanical properties, here is a very good review:   
Kloxin, A. M.; Kloxin, C. J.; Bowman, C. N.; Anseth, K. S., Mechanical Properties of Cellularly Responsive Hydrogels and Their Experimental Determination. Advanced Materials 2010, 22, (31), 3484-3494.
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16楼2013-01-14 20:20:42
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aircraftvip

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15楼: Originally posted by chenluyi0502 at 2013-01-14 14:13:55
呃~源链接我找不到了~因为是已经下载了的~我发在华为网盘上~这是外链:http://dl.vmall.com/c0wbddba69
你看看能不能下载~...

O.K.
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17楼2013-01-14 20:25:56
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aircraftvip

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红舟流星: 金币+2, 应助指数+1, 专家考核, 欢迎来到生物功能材料板块积极应助交流 2013-01-15 00:20:51
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17楼: Originally posted by aircraftvip at 2013-01-14 20:25:56
O.K....

The original article is this one where detailed information included:
Gong, J. P.; Kurokawa, T.; Narita, T.; Kagata, G.; Osada, Y.; Nishimura, G.; Kinjo, M., Synthesis of hydrogels with extremely low surface friction. J Am Chem Soc 2001, 123, (23), 5582-3.
......The poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) gel was synthesized by the radical polymerization. An aqueous solution of 1.0 M 2-acrylamido-2-methyl-1-propanesulfonic
acid (AMPS), 5.0 mol % cross-linking agent, N,N¢-methylenebisacrylamide(MBAA), and 0.1 mol % initiator, 2-oxoglutaric acid, in the reaction cell was purged with nitrogen gas for 30-45 min and was irradiated with UV light Sample Text. The reaction was carried out between a pair of polystyrene substrates or glass substrates, separated with a spacer 2 mm thick. After polymerization, the gel was immersed in a large amount of water for 1 week to equilibrate and to wash away the residual chemicals. ......

Without UV wavelength specification, the irradiation time was 5 h long in this paper, which seems unusual.
But in your case, you could try to increase the time to 30 min, for each side (top and bottom of the sample)
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18楼2013-01-14 22:37:27
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aircraftvip

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红舟流星: 编辑内容 2013-01-14 23:13
重复发帖,已编辑

[ Last edited by 红舟流星 on 2013-1-14 at 23:13 ]
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19楼2013-01-14 22:38:23
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aircraftvip

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黄酮: 金币+1, 专家考核,欢迎来生物材料应助 2013-01-15 09:36:09
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19楼: Originally posted by aircraftvip at 2013-01-14 22:38:23
The original article is this one where detailed information included:

Gong, J. P.; Kurokawa, T.; Narita, T.; Kagata, G.; Osada, Y.; Nishimura, G.; Kinjo, M., Synthesis of hydrogels with extremel ...

Sample Text = for 5 h at 25 °C

Sample Text= You could try to increase your exposure time to 30 min at least, for both sides (top and bottom)
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20楼2013-01-14 22:40:58
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