2013高分子光化学ch5

Emanuel Fleige, et al., Advanced Drug Delivery Reviews, 2012, 64(9): 866–884
3. 表征聚合物本体的通透性
主要针对多孔材料，考察小分子在材料中的渗透迁移速率。 将具有光漂白性的荧光染料均匀混入发泡或多孔聚合物材料， 材料表面因有荧光探针分子，而发射均匀荧光，对表面进行局 部光照漂白，观测表面荧光的恢复状况，内部荧光分子迁移至 表面的速率的即可测得，
TNT, meet graphene: Explosive sensor
AgNP enhanced the Raman spectroscopy of graphene, but quenched by TNT
Minmin Liu and Wei Chen of the State Key Laboratory of Electroanalytical Chemistry at Changchun Institute of Applied Chemistry, Biosens Bioelectron 2013, 46, 68-73: "Graphene nanosheets-supported Ag nanoparticles for ultrasensitive detection of TNT by surface-enhanced Raman spectroscopy"
（适于溶液聚合、本体聚合、分散聚合。乳液聚合情况复杂。）
RAFIK. O. LOUTFY, et al., Journal of Polymer Science: Polymer Physics Edition, Vol. 20,825-835 (1982)
2. 表征分子链形态变化
芘作为探针分子，不溶于水，可溶于酸性聚甲基丙烯酸水溶液 中，分子链类似胶束将芘包裹，发出较强荧光。中和后，聚合 物失去对芘的助溶能力，芘析出，荧光消失。说明聚合物链由 卷曲线团转变为伸展状。
其他常见荧光探针分子
b) 探针分子受溶剂或环境极性的影响
探针分子激发态处于电荷转移状态，极性增加，容易受溶剂和 环境影响，有不同程度的溶剂化，影响其荧光发射。
极性增加，发射峰红移
溶剂极性增加，溶剂化倾向越大，位能差越小，发射峰红移；
荧光跟踪聚合过程
探针分子加到聚合体系中，随聚合进行，体系极性降低，探针分 子荧光峰将蓝移，且随粘度增加，探针分子热运动受到抑制，激 发态热耗散减弱，荧光发射增强，伴随自加速。
Macromonomer for hydrogel
光交联质酸
Photoscissile Poly(ethylene glycol)-Based Hydrogel
长短波辐照－光控开光：
Fotios M. Andreopoulos
Photoscissable HG Synthesis via Photopolymerization of PEGBased Polymers without Photoinitiators J. Am. Chem. Soc. 1996, 118, 6235-6240
传统的生化检验 生物芯片技术：集成检验、集成合成
微通道同时充当毛细色谱柱，起分离作用
Process flow diagram of a typical fabrication sequence for silicon, glass, or quartz microfluidic devices
4. 活性自由基聚合 光活性的iniferter:
水凝胶，药物输送测试
4. 荧光聚合物探头
Structures of some important landmine chemical signature compounds
Why Using Fluorescent Polymer?
小分子荧光体 与 大分子荧光体之间的 荧光猝灭差异：
一种多米诺形式的荧光猝灭原理。
Ch 5. 聚合物光化学的应用
从前沿基础研究到工业应用 一种材料制造的新技术、新手段
从一般性工业技术到高技术制造 一项新型的朝阳产业
Application Field of Polymer Photochemistry
1. 2. As an analysis tool for polymer morphology and microphase; Employed for synthesis of polymers;
2. 液晶单体光聚合
UV curable liquid crystalline monomers.
a) 纤维表面原位光聚合， 增强纤维； b) 偏振光聚合，制作LCD retardation film； c) 原位光交联制作LCD反 射式偏光膜；
液晶光聚合动力学
液晶光交联-橡胶硫化
Nanoporous composites of polymerized lyotropic liquid-crystalline monomers, and hydrophobic polymers United States Patent 7090788
一、聚合物及过程的荧光表征手段
1.用于跟踪聚合过程 采用荧光探针技术，监测聚合体系的荧光强度及发射峰波长的 变化，从而定量跟踪聚合反应进程。 a) 荧光探针分子通常具有分子内电荷转移特点，一般具有芳环 和氨基结构，受光激发，能形成分子内电荷转移的激发态。
分子内电荷转移复合物处于激发态，常常释放荧光作为指示 信号。
3. 水凝胶的光合成
具有一定吸水性和较强生物降解活性的聚合物，用作药物和 营养缓释材料、保湿材料等。 常见吸水单体：
NH2 NH2 H N
O O
O O
IPMA
O R
N
N
OH
O
O
PEG O
O
hydrogels formed from acrylate modified poly(vinyl alcohol) macromers
光引发活性聚合机理
S CH2 S C N(Et)2 h S CH2 + S C N(Et)2 X CH2CH2 CH S S C N(Et)2 X S CH2CH2 CH S C N(Et)2 X S CH2 (CH2 CH)n S C N(Et)2
X CH2 + X CH2CH2 CH
监测水凝胶hydrogel体系的相变过程
温敏水凝胶体系，如 N- 异丙基丙烯酰胺的聚合物 PIPAAM ， 在较低温度下分子链成水合状态，即类似水溶液，吸水量较高。 荧光探针分子多为油溶性，此时不溶于该水合体系。升温至其 特有的最低临界溶液温度时（lowest critical solution temperature, LCST），聚合物链与水分子的作用发生突变，聚合物链去水合， 疏水基团聚集成胶束状，将油溶性探针分子包裹于其中，溶解 分散，发射出较强荧光。即从低温到高温经LCST转变时，发射 荧光经历从弱到强的突跃。
currently in use throughout Iraq and Afghanistan
Ultra-low Sensitivity: The exquisite sensitivity of the Fido XT is due to the unique amplifying fluorescent polymer (AFP) technology. AFP provides a detectable response to explosive materials at levels as low as a few femtograms (parts per quadrillion). This makes the unit a thousand times more sensitive than it's nearest competitors, and it's performance is comparable to that of highly trained explosive detection dogs.
Schematic representation of fluorescence recovery after photobleaching (FRAP) assay. A small spot in a hydrogel containing fluorescent probe is photobleached, and the increase of fluorescence in the photobleached area was measured over time (from 1 to 6). - CHAENYUNG CHA, DESIGN OF MULTI-FUNCTIONAL HYDROGEL FOR CELL THERAPIES
3.
4.
Used for modification of polymers;
Manufacture of microfabrication;
5.
6.
Applied in electronics and photo-communication;
UV-curable coating, ink and adhesive.
O HO
N O
荧光探针分子：黄酮类化合物
水凝胶相转变过程 吸水率 与 荧光强度变化
Water swelling %
IF
Temperature
Fluorescent images and schematic illustration of vesicles from PEO-b-PNIPAAM copolymer. The copolymer forms polymersomes at 37 °C, since the PNIPAAM block is hydrophobic above its LCST, while below the LCST (25 °C) the PNIPAAM block is hydrophilic and the vesicles fall apart. The membrane was labeled with PKH 26.
二、聚合物的光合成
1.常规光聚合 常见光聚合基团或单体：
O R O O O R
O R O
R O O
R
R
R'
O
O O
O O
DVE-3 Bisphenol A epoxy resin
O
O
O
O
O O O
cycloaliphatic epoxy resin
O
O O O
oxetane
O O
OHale Waihona Puke Baidu
O
O
New Monomer for cationic photopolymerization
Reversible Surface Properties of Glass Plate and Capillary Tube Grafted by Photopolymerization of N-Isopropylacrylamide
Microfluidic technique－ photoresist
Jason C. Sanchez, et al., J. Mater. Chem., 2008,18, 5134-5141
Fido® XT Explosives Detector
Applications: •Fieldable Trace Explosives Detection •People Screening •Vehicle Screening •IED Detection •Forensics Screening •Cargo Screening
For example,
荧光急剧猝灭
Design of the Photochemosensor
Pix of the Commercial Product
Polymerization of a boronate-functionalized fluorophore by double transesterification: applications to fluorescence detection of hydrogen peroxide vapor