大分子自组装研究的进展_江明

1、大分子自组装研究的进展大分子自组装研究的进展Studies on Macromolecular Self-assembly 江江 明明复旦大学高分子科学系复旦大学高分子科学系分子组装是最普遍的物理化学现象，是构建生命体系的基本途径大分子自组装是超分子化学和高分子科学的交大分子自组装是超分子化学和高分子科学的交叉领域叉领域Macromolecular self-assembly - interdisciplinary research field Important Part of Supramolecular Chemistry and polymer science 大分子自组装是创造具有纳

2、米或亚微米尺度的大分子自组装是创造具有纳米或亚微米尺度的结构新物质的简单和清洁的途径结构新物质的简单和清洁的途径Simple and clean ways to create new , structured polymeric materials (soft matters) in nano or sub-micro sizes 美国科学杂志于美国科学杂志于20052005年出版专刊，提出了年出版专刊，提出了2121世纪亟待解决的世纪亟待解决的2525个重大科学问题，个重大科学问题，化学自组装是其中唯一的化学问题化学自组装是其中唯一的化学问题。Robert F. Service Scienc

3、e 2005, 309, 95.Macromolecular Self-assembly :大分子自组装的两重含义：大分子自组装的两重含义：以大分子为组装单元构建组装体以大分子为组装单元构建组装体Macromolecules as building blocks to form structured assemblies以小分子为组装单元构建超分子聚合物以小分子为组装单元构建超分子聚合物Small molecules as building blocks to form Supramolecular Polymers A Ciferri, Macromolecular Rapid Commun

4、ications, 2002, 23, 511ABNNOOOHO4OOHBuilding blocks : small molecules with proton-donating and proton accepting groups NNOOOHO4OOHNNOHOABNOONOOORORNNNNNNButButButButHHHHNOONOOORORNNNNOOOOHHNOONOOORORNNNNNNButButButButHHHHNOONOOORORNNNNOOOOHHNNNNHHNNOONHButButSupramolecular PolymersA Little work in C

5、hina Macromolecules as building blocks to form structured assemblies Micellization of block copolymers in selective solvents Covalent bonds connecting the core and shellselective solvent for red blockselective solvent for blue blockCharacters:Size 10-200nmAmphiphilicity Applications:Encapsulation Dr

6、ug-delivery,Micro-reactor:Nano-metal particles,Nano-semi-conductor particlesCatalysis至至80年代末我国无系统性大分子自组装研究年代末我国无系统性大分子自组装研究先驱性的研究先驱性的研究Pioneer work 90 年代初年代初吉林大学吉林大学 沈家骢沈家骢, 张希等张希等 气气/ /液界面液界面“浮萍浮萍”与与“倒浮萍倒浮萍”膜组装膜组装微相分离微相分离间隔基效应间隔基效应两亲性聚合物两亲性聚合物 聚合物自组织层状结构聚合物自组织层状结构（有序性与稳定性相结合）（有序性与稳定性相结合）界面组装界面组装 提出

7、了类提出了类“浮萍浮萍”与与“倒浮萍倒浮萍”聚合物超薄膜的模型，利用亲、疏水聚合物超薄膜的模型，利用亲、疏水力进行组装，为解决聚合物膜的稳定性与有序度相矛盾的问题提供了新思力进行组装，为解决聚合物膜的稳定性与有序度相矛盾的问题提供了新思路。路。沈家骢、张希等沈家骢、张希等Langmuir, 1994, 10, 2727Thin Solid Films, 1992, 210, 625Macromolecules, 1991, 24, 4986 Macromolecules, 1990, 23, 5158浮萍浮萍倒浮萍倒浮萍airwaterairwater系列学术研讨会系列学术研讨会1991199

8、1年年沈家骢沈家骢 H. Ringsdorf长春夏季化学研讨会：有序功能体系长春夏季化学研讨会：有序功能体系国际香山科学讨论会国际香山科学讨论会- -1994年年 超分子体系1998年年 超分子体系超分子体系: :从分子构筑到功能组装从分子构筑到功能组装20012001年年超分子体系：材料科学与生命科学间的桥梁超分子体系：材料科学与生命科学间的桥梁20042004年年超分子体系：从微米超分子体系：从微米/ /纳米结构研究材料科学和生物技术的方法纳米结构研究材料科学和生物技术的方法 杨柏杨柏, 吉林大学吉林大学张希张希, 清华大学清华大学高长有高长有, 浙江大学浙江大学Supramolecula

9、r Layered Structure Multi-layer membreneNano-pattering of surface Hollow micro-encapsulesNNNNUV Vis01234567801234ln(A0-Aeq)/(At-Aeq)Time (min)01234560.070.090.110.130.15Abs at 320 nmNumber of cycles基于高分子胶束的层状组装：偶氮苯分子的包覆与光基于高分子胶束的层状组装：偶氮苯分子的包覆与光致异构化速率的提高致异构化速率的提高 一般偶氮苯在固态膜中的光致异构化一般偶氮苯在固态膜中的光致异构化速率和效率

10、常常比其在溶液中低。我们巧速率和效率常常比其在溶液中低。我们巧妙的利用高分子胶束结构所提供的微环境，妙的利用高分子胶束结构所提供的微环境，使偶氮苯光致异构化的速率在固态膜中比使偶氮苯光致异构化的速率在固态膜中比其在溶液中还快一倍。其在溶液中还快一倍。 LbL 薄膜薄膜甲苯溶液甲苯溶液张希张希 等等 et al. Langmuir, 2006, 22, 39064.0710-3 9.0310-3 1.1410-2 复旦大学复旦大学 Fudan UniversityMing Jiang （江明）（江明）Daoyong Chen （陈道勇）（陈道勇）Ping Yao （姚萍）（姚萍）90年代初，年代

11、初， 研究兴趣在高分子研究兴趣在高分子氢键相互作用和相容性问题氢键相互作用和相容性问题C CF3F3COHCH CH2CH CH2nmCH2CO=COCH3CH3nPS(OH)-X X 8mol% PMMAABsegment pairing interpolymer complex 大分子络合物大分子络合物 驱动力：氢键驱动力：氢键 自发过程自发过程 分子组装？分子组装？Each A chain interacts with many B chains and vice versa 无规则的聚集体无规则的聚集体separated coils +common solvent我们反复思考的问题是：

12、能否通过高分子间的络合作用实现能否通过高分子间的络合作用实现规则组装规则组装？我们提出并成功地实现了我们提出并成功地实现了 “高分高分子胶束化的非嵌段共聚物路线子胶束化的非嵌段共聚物路线”“Block-copolymer-free routes for polymeric micellization via interpolymer complexation ”Interaction groups将质子给体基限于链的端将质子给体基限于链的端基上基上Restricting the reaction groups within certain positions along the chainOn

13、e of Approacheshydrogen bonding leads to graftcopolymers and then 非共价键合胶束非共价键合胶束(NCCM)Proton donor endsProton acceptorNCCMInobverse and reverse NCCM of CPB/ PVPyPVPyCPBnitromethaneIn chloroformObverse NCCMNCCMReverse NCCMNCCMhexaneNpolybutadiene with carboxyl groups at ends1001011021030123 f(Dh)Dh (

14、nm)PVPy-(CPB)(PVPy)-CPBHydrodynamic Diameter (Dh) Distribution多种途径实现“非嵌段共聚物胶束化”均聚物，离聚物，齐聚物，接枝共聚物等均可用为组装单元这是具有普遍意义的路线：这是具有普遍意义的路线：Polyimide / PVPy-containing polymersJACS ,123, 12097, 2001; J Phys Chem B, 108, 550, 2004; 108, 5225, 2004Carboxyl-end polybutadiene (CPB) / Poly(vinyl alcohol)(PVA) - Mac

15、romolecules ,37, 1537, 2004Poly(carprolactone)(PCL) / Poly(acrylic Acid) (PAA) , Langmuir 21, 1531 , 2005Poly(styrene-co-MAA) / Poly(vinlpyrollidone)Langmuir ,17,6122, 2001PCL/ PMAA-g-PCLAngew Chem Intl Edi, 41, 2950, 2002利用核利用核-壳壳“非共价非共价”连接，通连接，通过壳交联和核溶解获得空心球过壳交联和核溶解获得空心球Great interest in obtaining

16、polymeric hollow spheres:Liu G, Wooley Kdegradablecrosslinkableblock copolymerselective solventcrosslinkingphoto-degradationchemical-degradationFrom NCCM to Hollow Spheres crosslnking PVPy shell by 1,4 dibromobutane in CH3NO2Cavitation in DMF CH3NO2PS(OH)PVPyDMFTEM Image of Hollow Sphere obtained by

17、 core dissolution from NCCM of (PCL)-PAA环境响应胶束：环境响应胶束：pH, 温度，温度，光，离子强度等光，离子强度等Hydroethyl Cellulose (HEC) g Poly(Acrylic Acid) HEC-g-PAASelf-assembly of Double Hydrophilic Graft CopolymerDou HJ, Jiang M et al. Angew Chem Intl Ed 42, 1516, 2003Ce()/H+CHCH2COOHmPAA graftOHHHOHHOHCH2OCH2CH2OCH2CH2OHHOHH

18、CH2OCH2CH2OCH2CH2OHHOCH2CH2OHHOHHOOnHEC backboneHEC-g-PAAOHHHOHHOHCH2OCH2CH2OCH2CH2OHHOHHCH2OCH2CH2OCH2CH2OHHOCH2CH2OHHOHHOOn+CHCH2COOHPreparation of graft coplymer接枝共聚物分子量的表征接枝共聚物分子量的表征Characteristic data of HEC-g-PAA copolymersSample No.AA:AGU a (molar radio)M10-5(HEC backbone)M10-5 b(PAA grafts)A

19、veragegraft pointFeed compositionPolymer compositionCAA-00.23:10.25:10.9CAA-11.17:11.28:10.90.1751.58CAA-23.50:12.54:10.90.2102.61Cellulase+PAA graftsAGUTable 2-2 LLS Characteristic data of CAA-1 and CAA-2Sample No.Mw10-5 a(HEC-g-PAA)b/ nm/ nm/CAA-11.6753.8401.49CAA-23.3375.659.61.58/=1.50Means rand

20、om coilRadius of Gyration RgHydrodynamic Radius Rh02468101214100200300400500 /nmpH CAA-2 CAA-1The solution at pH range of 2-3 was unstable: the apparent increased with time. The values measured 20 min after the solution preparation were used. Figure 3-2 of HEC-g-PAA copolymers as a function of pH. T

21、he concentration was 1mg/ml. HEC-g-PAAMicellespH 3, molecularly dissolvedpH3)-COOH of PAA at pH3 can complex with HEC and form the “core” of micellesUncomplexed HEC segments form the “shell” of micelles (pH 3, molecularly dissolvedAt low pH, PAA protonated, forming complex with HEC main chain core;

22、HEC without PAA branches formed shell pH-controlled complexation-induced micellization (low grafting density is necessary!)COOH COO- + H+pH pH At low pH, Crosslinking of PAA grafts - to lock the structureDialysis against water, pH 3 7: DLS: size 350nm 650nmTEM: micelles hollow spheresAt pH 7, Hollow

23、 Spheres Form! pH 3-7:pH-dependent micelle-hollow- sphere transition pH1.3交联交联PAApH increaseCore-crosslinked miclle Low crosslinking density is necessary !pH=1.3Stable micelle交联剂：交联剂：2,2-(ethylenedioxy)bis(ethylamine) Dialysis pH=7PAA+HECdecomplexationReversible ?pH 3, protonation,complexation pH7,

24、deprotonation, de-complexation, disintergaration 1234567300350400450500550600650700pH increasepH decrease DialysisDialysisDhpHReversibility of the transition pH 3-7:pH-dependent micelle-hollow- sphere transition TEM observationsTEM observations（CAA2CAA2）pH=1.3pH induced micellespH=7Hollow spherespH=

25、1.3pH-induced micelles after one pH cycle15202530354045200250300350400450 / nmTempeature / oC H10-5, heating H10-5, cooling PNIPAM (Polyisopropyl acrylamide) -based reversible thermo-sensitivityAdv Funct Mat 15, 695 (2005)456789100200300400500dialysisdialysis / nmpH5.88.54.5PAA-based pH 4.5 8.5, vol

26、ume increases by 130 timesLangmuir 21, 1531 (2005)Building block : linear polymersArchitectural effect ?Dendrimer and Dendron as building blocks Preparation of Dendron G3H-Bonding Dendronized Polymers Formation of nanoparticles from G3/PVP in common solvent , ultrasonic treatment Hollow spheres? Col

27、lapsed thin-layer hollow spheres ?Crosslinked hollow spheres - much high strength G3/PVP23Thick wall hollow spheres Self-assembly driven by H-BondingOther driving forces? Inclusion complexation ?- CD- CD- CDNo. of glucose units 678cavity diameter, 5.3 8.3height of torus, 7.9 diameter of outher perip

28、hery, 14.615.4 17.5 approx volume of cavity, 3174 262 427 环糊精环糊精cyclodextrin 7OHOOHOH*O* hydrophilicityhydrophobicityStructures and properties of Adamantane (ADA)d 7 7 V 180 3 262 3Adamantane Complex stable constant 105The -CD cavity apparently has the optimum dimensions for interaction with adamant

29、ane derivate.7 Adamantane CD环糊精环糊精 是研究的最多的作用主体是研究的最多的作用主体在高分子方面主要是用于多聚轮烷在高分子方面主要是用于多聚轮烷-CD / PEO-CD / PEO如何将环糊精的包结络合用于构建高分如何将环糊精的包结络合用于构建高分子胶束？子胶束？ 通过通过inclusion complexation 构建高分子胶束构建高分子胶束基本思路：基本思路： 合成分别带合成分别带CD和和ADA的亲水和疏水高分子，的亲水和疏水高分子， 在水中形成通过在水中形成通过inclusion interaction 连接的核连接的核壳胶束（壳胶束（NCCM） ATRP

30、Mn =1.67 x 104Mw/Mn =1.21Mn =1.87 x 104Mw/Mn =1.28CD-containing monomer GMA-CDPGMA-CD MW 10,400Characters:Double-scale hydrophobic regions : 100nm and 0.7nmCavities available for surface modification NH2-COOHnegatively chargedpositively chargedMicelle surface modification Hollow sphere of crosslinke

31、d PGMA-CDDouble Scale Cavities 环糊精的包结络合在大分子组装研究中有很大的发展空间环糊精的包结络合在大分子组装研究中有很大的发展空间:表面活性剂表面活性剂; 纳米金属粒子纳米金属粒子; 光响应有机分子光响应有机分子; 催化催化陈道勇等：陈道勇等： 聚合反应聚合反应/组装同步法组装同步法合成合成纳米纳米结构结构Macromolecules 2005, 38 , 3550 Most-Accessed Articles: 20051.Nanoporous Polystyrene Containing Hydrophilic Pores from an ABC Tribl

32、ock Copolymer PrecursorRzayev, J.; Hillmyer, M. A.Macromolecules 2005, 38(1), pp 3-5. 2.A One-Pot Approach to the Preparation of Organic Core-Shell Nanoobjects with Different MorphologiesPeng, H.; Chen, D.; Jiang, M.Macromolecules 2005, 38(9), pp 3550-3553. 3.Synthesis and Direct Visualization of Bl

33、ock Copolymers Composed of Different Macromolecular ArchitecturesPyun, J.; Tang, C.; Kowalewski, T.; Frechet, J. M. J.; Hawker, C. J.Macromolecules 2005, 38(7), pp 2674-2685. 4.Deep-Red Electroluminescent Polymers: 4.Synthesis and Characterization of New Low-Band-Gap Conjugated Copolymers for Light-

34、Emitting Diodes and Photovoltaic DevicesYang, R.; Tian, R.; Yan, J.; Zhang, Y.; Yang, J.; Hou, Q.; Yang, W.; Zhang, C.; Cao, Y.Macromolecules 2005, 38(2), pp 244-253. 2005 据2005 全年第二陈道勇，陈道勇， 江明江明 Account of Chemical Research , 38, 494, 2005Strategies for Constructing Polymeric Micelles and Hollow Sp

35、heres in Solution via SpecificIntermolecular Interactions新挑战：从合成高分子到天然大分子Target Materials : Micelles or Nano core-shell hydrogel made of proteins and polysacchrids biocompatible, biodegradable, non-toxic and even eatable （可食用性）（可食用性）Ping Yao (姚萍）， Fudan UniversityOvalbumin(白蛋白） and Lysozyme（溶菌酶）Oval

36、bumin: 385 aa, Mw 47000 DaIsoelectric Point 4.7, 7 nm 4.5 nm 5 nmLysozyme: 129 aa, Mw 14351 Da Isoelectric Point 10.7, 3.8 nm 2.4 nm 2.2 nm5.34.710.7已寻求到合适途径获得核壳纳米微凝胶已寻求到合适途径获得核壳纳米微凝胶Mixing at pH 5.3, weak interaction Adjust pH 10.3, Lys aggregates, Oval Protection Heat denatured具有普遍意义的途径具有普遍意义的途径 G

37、lobular + Globular:Ovalbumin and LysozymeBovine Serum Albumin and LysozymeOvalbumin and Overtransferrin Linear + Globular:as-Casein + Overtransferrin(as,beta,kappa-)Casein + Lysozyme Globular proteins + PolysaccharideOvalbumin + ChitosanYao et al: Langmuir 22, 2754, 2006 Biopolymers 81, 29, 2006 J Collois Interface Sci., in press Biopolymers in press 其他研究小组的成果其他研究小组的成果传统的嵌段共聚物在选择性溶剂中的传统的嵌段共聚物在选择性溶剂中的自组装的研究已很少自组装的研究已很少兴趣集中于新的组装单元，新组装途兴趣集中于新的组装单元，新组装途径，新驱动力，聚电解质等径，新驱动力，聚电解质等颜德岳等颜德岳等上海交