New photoresponsive (meth)acrylate (co)polymers containing azobenzene pendant sidegroups with carboxylic and dimethylamino substituents—II. Synthesis and characterization of polymers and copolymers

Haitjema, Hj; Buruma, R.; Ekenstein, G.O.R. Alberda van; Tan, Y.Y.; Challa, G.

doi:10.1016/s0014-3057(97)80004-3

Cited by 15 publications

(15 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Most side chain azo polymers were synthesized via free radical polymerization but with the disadvantage of uncontrolled molecular weights and relative high polydispersity index values (PDIs) 14–25. In view of these drawbacks, Solaro and coworkers26 and Aoshima and coworkers27 reported the synthesis of copolymers with azobenzene side groups via living anionic and cationic polymerization, respectively.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of azobenzene‐containing polymers via RAFT polymerization and investigation on intense fluorescence from aggregates of azobenzene‐containing amphiphilic diblock copolymers

Zhang

Zhou

et al. 2008

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

The well-defined azobenzene-containing homopolymers, poly{6-(4-phenylazophenoxy)hexyl methacrylate (AHMA)} (PAHMA), were synthesized via reversible addition fragmentation chain transfer polymerization (RAFT) in anisole solution using 2-cyanoprop-2-yl 1-dithionaphthalate (CPDN) as the RAFT agent and 2,2 0 -azobisisobutyronitrile (AIBN) as the initiator. The first-order kinetic plot of the polymerization and the linear dependence of molecular weights of the homopolymers with the relatively low polydispersity index values (PDIs 1.25) on the monomer conversions were observed. Furthermore, the amphiphilic diblock copolymer, poly{6-(4-phenylazophenoxy)hexyl methacrylate (AHMA)}-b-poly{2-(dimethylamino)ethyl methacrylate (DMAEMA)} (PAHMA-b-PDMAEMA), was prepared with the obtained PAHMA as the macro-RAFT agent. The structures and properties of the polymers were characterized by 1 H NMR and GPC, respectively. Interestingly, the amphiphilic diblock copolymers in chloroform (CHCl 3 ) solution (PAHMA 23 -b-PDMAEMA 97 (4 3 10 À5 M, M n(GPC) ¼ 18,400 g/mol, PDI ¼ 1.48) and PAHMA 28 -b-PDMAEMA 117 (6 3 10 À5 M, M n(GPC) ¼ 19,300 g/mol, PDI ¼ 1.51) exhibited the intense fluorescence emission at ambient temperature. Moreover, the fluorescent intensity of PAHMA-b-PDMAEMA in CHCl 3 was sensitive to the ultraviolet irradiation at 365 nm, which increased within the first 10 min and later decreased when irradiation time was prolonged to 30 min or longer. The well distributed, self-assembled micelles composed of azobenzene-containing amphiphilic diblock copolymers, (PAHMA-b-QPDMAEMA)s (QPDMAEMA is quaternized PDMAEMA), in the mixed N,N-dimethyl formamide (DMF)/H 2 O solutions were prepared. Their fluorescent intensities decreased with the increasing amount of water. V V C 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: [5652][5653][5654][5655][5656][5657][5658][5659][5660][5661][5662] 2008

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis of azobenzene‐containing polymers via RAFT polymerization and investigation on intense fluorescence from aggregates of azobenzene‐containing amphiphilic diblock copolymers

Zhang

Zhou

et al. 2008

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…The result indicates that Azo-M is difficult to polymerize [38] and need much time to form perfect core-shell structure due to the steric effect. As shown in Figure 1(c) and (d), decreasing the amount of acetonitrile solvent to 80 mL (i.e.…”

Section: Resultsmentioning

confidence: 99%

Synthesis and photo-responsive behaviors of hollow polyazobenzene micro-spheres

Wang

Yang

et al. 2010

Chin. Sci. Bull.

View full text Add to dashboard Cite

By means of distillation precipitation polymerization, the silica-hybrid particles with polyazobenzene shell (PAzo@SiO 2 ) microspheres were prepared with 6-(4-methoxy-4′-oxy-azobenzene) hexyl methacrylate (Azo-M) as monomer, divinylbenzene (DVB) as cross-linker, and ~250 nm vinylated sol-gel silica particles as template. Hollow polyazobenzene microspheres were further developed after selective removal of the silica cores with HF solution. When the content of DVB related to Azo-M is 20 wt%, the acetonitrile is 200 mL, and the polymerization time is 4.5 h, the hollow PAzo microspheres with about 20 nm shell are successfully fabricated. These hollow PAzo microspheres have excellent reversible photoisomerization, and their first-order rate constant of trans-cis isomerization only decreases 11.8% compared with homopolymer of azobenzene (Homo-PAzo).hollow micro-spheres, azobenzene, photoresponsive behavior Citation:Wang X T, Yang Y K, Yang Z F, et al. Synthesis and photo-responsive behaviors of hollow polyazobenzene micro-spheres.

show abstract

“…Two important trends can be distinguished in the values of the trans absorption maximum (λ max ; π–π*): a polymer composition effect and a substituent effect 56. Azobenzene moieties are capable of the formation of aggregates that strongly influence their electronic properties and thus the UV spectra, being caused by π/π interactions between adjacent azobenzene groups 57.…”

Section: Resultsmentioning

confidence: 99%

“…The effect of the copolymer composition on λ max is not observed for polymers in which the azobenzene side group is separated from the polymer backbone by a flexible spacer. Probably no interaction takes place because the spacer allows the azobenzene groups to move independently of the polymer backbone and one another 56…”

Section: Resultsmentioning

confidence: 99%

Effect of the terminal substituent of azobenzene on the properties of ABA triblock copolymers via atom transfer radical polymerization

Tang

Gao

Fan

et al. 2007

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

The effect of the terminal substituent of azobenzene on the properties of ABA triblock copolymers was investigated. For this study, three kinds of azobenzene-containing monomers with different terminal substituents-6-[4-(4-methoxyphenylazo)phenoxy] hexyl methacrylate, 6-[4-(4-ethoxyphenylazo)phenoxy]hexyl methacrylate, and 6-[4-(4nitrophenylazo)phenoxy]hexyl methacrylate-were used to synthesize ABA triblock copolymers PMMAzo 25 -PEG 13 -PMMAzo 25 /PMMAzo 12 -PEG 13 -PMMAzo 12 , PEMAzo 14 -PEG 13 -PEMAzo 14 , and PNMAzo 14 -PEG 13 -PNMAzo 14 , respectively, by atom transfer radical polymerization (PMMAzo is poly{6-[4-(4-methoxyphenylazo)phenoxy]hexyl meth-acrylate}, PEMAzo is poly{6-[4-(4-ethoxyphenylazo)phenoxy]hexyl methacrylate}, and PNMAzo is poly{6-[4-(4-nitrophenylazo)phenoxy]hexyl methacrylate}). These copolymers were characterized with 1 H NMR spectroscopy and gel permeation chromatography and exhibited controlled molecular weights and narrow molecular weight distributions. Differential scanning calorimetry and polarizing optical microscopy showed that these copolymers had mesophases. PMMAzo 25 -PEG 13 -PMMAzo 25 and PMMAzo 12 -PEG 13 -PMMAzo 12 had a smectic mesophase and a nematic mesophase, whereas both PEMAzo 14 -PEG 13 -PEMAzo 14 and PNMAzo 14 -PEG 13 -PNMAzo 14 had a nematic mesophase. This demonstrated that the liquid-crystalline properties of these copolymers highly depended on the terminal substituent of azobenzene. The photoresponsive behavior of these copolymers was also investigated in tetrahydrofuran solutions, and the influence of the terminal substituents attached to azobenzene was studied. V V C 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5190-5198, 2007

show abstract

New photoresponsive (meth)acrylate (co)polymers containing azobenzene pendant sidegroups with carboxylic and dimethylamino substituents—II. Synthesis and characterization of polymers and copolymers

Cited by 15 publications

References 21 publications

Synthesis of azobenzene‐containing polymers via RAFT polymerization and investigation on intense fluorescence from aggregates of azobenzene‐containing amphiphilic diblock copolymers

Synthesis of azobenzene‐containing polymers via RAFT polymerization and investigation on intense fluorescence from aggregates of azobenzene‐containing amphiphilic diblock copolymers

Synthesis and photo-responsive behaviors of hollow polyazobenzene micro-spheres

Effect of the terminal substituent of azobenzene on the properties of ABA triblock copolymers via atom transfer radical polymerization

Contact Info

Product

Resources

About