UV‐induced crosslinking of ring opening metathesis block copolymer micelles

Abstract

Statistical and amphiphilic block copolymers bearing cinnamoyl groups were prepared by ring opening metathesis polymerization (ROMP). The UV‐induced [2 + 2] cycloaddition reaction of polymer bound cinnamic acid groups was studied in polymer thin films as well as in block copolymer micelles. In both cases, exposure to UV‐light for 10 min led to a crosslinking conversion of about 60%, as determined by FT‐IR spectroscopy and UV–vis absorption measurements. Time based IR‐spectroscopy revealed a maximum conversion of 78% reached after an irradiation time of about 16 min. For micelles obtained from polymers bearing 5 mol % or more cinnamoyl groups, the crosslinking reaction proceeded smoothly, yielding in crosslinked particles which were stable in a non‐selective solvent (CHCl3). Diameters determined by dynamic light scattering in the selective solvent (MeOH) were similar for both, non‐crosslinked and crosslinked micelles, whereas diameters of crosslinked micelles in the non‐selective solvent (CHCl3) were significantly larger compared to MeOH samples. This strategy of direct self assembly of block‐copolymers in a selective solvent followed by “clean” crosslinking, without the need for additional crosslinking reagents or crosslinking initiators, provides a straight forward approach toward ROMP‐based polymeric nano‐particles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2402–2413, 2008

Dye-functionalized polymers via ring opening metathesis polymerization: principal routes and applications

“…Adapted with permission from [29]. Copyright (2011) American Chemical Society molar ratios so that tailor-made block copolymers can be achieved easily [21,[40][41][42][43][44][45][46][47]. In addition to the tailored design of highly specific materials for bioimaging and visualization of tumor cells, even unspecifically labelled, self-assembled nanoparticles can be applied for e.g.…”

“…[2.2.1]Bicyclohept-5-enederivatives (norbornenes) are the most common monomers in ROMP, as a huge variety of different monomers can be [15][16][17], pentacene [18], tetracene [18] Anthracene [15,17], pyrene [19], benzothienobenzothiophene [20] --Anthracene [74] Fluorene [90] (Hetero)cycles Perylene bisimides [21][22][23][24], hexabenzocoronene [25][26][27], quinolone [26], pyrene [29] Phenanthroimidazole [30,31] perylene bisimides [21], quinizarine [32], phenoxynaphthacene [33] Perylene bisimides [21] Phenanthroimidazole [11], perylene bisimides [8], pyrene [9] Coumarin [79] Benzoxazole [81] Benzoxazole [76,90] a Triphenylmethane dyes (Dichloro)fluorescein [40], eosin [40] Eosin [41] Oregon Green 488 [42], rhodamin B [43], rhodamin [44], fluorescein [44], eosin [45][46][47] Fluorescein [10] Rhodamin, [10,…”

“…A wide range of suitable monomers has been copolymerized comprising (hetero)polyaromatic compounds [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33], and more sophisticated functionalities like conjugated oligomers [34][35][36][37][38][39], triphenylmethane [40][41][42][43][44][45][46][47], azo [48][49][50][51][52], or polymethine [53][54][55][56][57] dyes. Even transition metal coordination compounds of aluminum [58,59], iron [60], zinc [61][62][63], ruthenium [64, 65], europium …”

Phosphonic acid‐based amphiphilic diblock copolymers derived from ROMP

“…3 Ring-opening metathesis polymerization (ROMP) is a versatile technique for the preparation of well-defined block copolymers with narrow distribution of molecular weights. Several amphiphilic block copolymers obtained by the ROMP pathway have been investigated in the literature and were shown to form micelles and nanoparticles, [4][5][6][7][8][9][10][11][12][13][14] and used as drug delivery materials. [15][16][17] Phosphorus-containing polymers have broad application areas; besides their flameretardant properties, 18 they are also used in biomaterials for their adhesive properties to metals, bone, and dentin.…”

Highly ordered nanoporous thin films by blending of PSt‐b‐PMMA block copolymers and PEO additives as structure directing agents

“…envisaged for these materials. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] It is now well established that the structural characteristics of block copolymer thin films can be controlled by manipulation of molecular weight, block volume fraction, and the interaction parameter, v. 1,4,5 In turn the orientation of the block domains in thin films is governed by boundary conditions such as commensurability and interfacial interaction between blocks and substrates. 1,4,5 In controlling the orientation of block copolymers in thin films, several strategies have been employed including surface modification, [17][18][19][20] solvent annealing, 21 electric fields, 22 graphoepitaxy, 23 chemical prepatterning, 24,25 shear, 26 etc.…”