A simplified procedure of anionic polymerization of styrene and dienes using 4,5-methylenephenanthrene as an indicator

Sänger, Jörg; Tefehne, C.; Lay, R.; Gronski, W.

doi:10.1007/bf00296003

Cited by 12 publications

(12 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As block segments, poly(1,2-butadiene) (PB, later the photoaddressable block) and polystyrene (amorphous matrix) were chosen, owing to the well-established living anionic polymerization of the two monomers. [8] The polystyrene-block-poly(1,2-butadiene) block copolymers were synthesized according to the procedure described by Bates et al, [9] Sänger et al, [10] and Böker et al [11] The double bonds in the poly(1,2-butadiene) segment were converted into hydroxy functions via a polymer-analogous hydroboration reaction using 9-borabicyclo[3.3.1]nonane according to the procedure described by Böker et al [11] and Chung et al [12] Finally, the azo and mesogenic units were covalently attached to the polyalcohol via a polymer-analogous esterification using a mixture of the corresponding acid chlorides.…”

Section: Materials Synthesis and Characterizationmentioning

confidence: 99%

Holographic Gratings in Diblock Copolymers with Azobenzene and Mesogenic Side Groups in the Photoaddressable Dispersed Phase

Häckel

Kador

Kropp

et al. 2005

Adv Funct Materials

View full text Add to dashboard Cite

Diblock copolymers, consisting of a photoaddressable mesogen‐containing dispersed phase and a polystyrene matrix, have been synthesized and characterized as holographic data storage materials. The photoaddressable phase contains p‐methoxy‐substituted azobenzene side groups and benzoylbiphenyl mesogenic side groups in a statistical distribution. Three‐ring mesogenic groups in combination with photoaddressable azobenzene side groups have been introduced for the first time in block copolymers in order to increase the local refractive‐index difference between illuminated and non‐illuminated volume elements, as well as to improve the stability of the orientation, while, at the same time, decreasing the optical density. To this end, a series of block copolymers with different azobenzene/mesogen ratios have been synthesized. The light‐induced reorientation dynamics of the chromophores and mesogens and the long‐term stability of the orientation have been studied with volume holographic measurements. A remarkable increase in stability of the holographic gratings has been achieved.

show abstract

Section: Materials Synthesis and Characterizationmentioning

confidence: 99%

Holographic Gratings in Diblock Copolymers with Azobenzene and Mesogenic Side Groups in the Photoaddressable Dispersed Phase

Häckel

Kador

Kropp

et al. 2005

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…The macroinitiator consisting of a linear polystyrene (PS) block and a linear hydroxylated polybutadiene (PB‐OH) block that was prepared as described by Gronski et al19,20…”

Section: Experimental Partmentioning

confidence: 99%

Linear‐Hyperbranched Amphiphilic AB Diblock Copolymers Based on Polystyrene and Hyperbranched Polyglycerol

Barriau

Marcos

Kautz

et al. 2005

Macromol. Rapid Commun.

View full text Add to dashboard Cite

Summary: A convenient three‐step strategy has been developed for the preparation of well‐defined amphiphilic, linear‐hyperbranched block copolymers by hypergrafting. The synthetic procedure is based on a combination of carbanionic polymerization with the alkoxide‐based, controlled ring‐opening multibranching polymerization of glycidol. A linear AB diblock copolymer polystyrene‐block‐polybutadiene (PS‐b‐PB) with narrow polydispersity was obtained by anionic copolymerization. Subsequent hydroxylation by hydroboration led to PS508‐b‐(PB‐OH)56, used as macroinitiator for the polymerization of glycidol under slow monomer addition conditions.Structure of the linear‐hyperbranched amphiphilic AB diblock copolymer PS508‐b‐(PB56‐hg‐PGx) and an AFM micrograph of its micellar core–shell structure observed after solution casting.magnified imageStructure of the linear‐hyperbranched amphiphilic AB diblock copolymer PS508‐b‐(PB56‐hg‐PGx) and an AFM micrograph of its micellar core–shell structure observed after solution casting.

show abstract

“…Sänger et al synthesized block copolymers containing 1,2-butadiene repeating units to modify the double bonds in further reaction steps for the first time. [24] With cyclohexane as solvent and sec-butyllithium as initiator they achieved an 1,2-content up to 100 mol-%.…”

Section: Synthesis and Characterization Of The Block Copolymersmentioning

confidence: 99%

“…Poly(1,2-butadiene)-block-polystyrene block copolymers were synthesized according to a procedure described by Sänger [24] and Bates. [25] The polymerization was started with the stereospecific polymerization of 1,3-butadiene in cyclohexane as solvent, using DIPIP as complexation agent.…”

Section: Synthesis and Characterization Of The Block Copolymersmentioning

confidence: 99%

See 1 more Smart Citation

Diblock Copolymers with Azobenzene Side‐Groups and Polystyrene Matrix: Synthesis, Characterization and Photoaddressing

Frenz

Fuchs

Schmidt

et al. 2004

Macro Chemistry & Physics

View full text Add to dashboard Cite

Summary: Diblock copolymers with a photoaddressable dispersed phase containing p‐methoxy substituted azobenzene side groups and a polystyrene matrix were synthesized and characterized. The block copolymers were prepared by a sequential living anionic polymerization of butadiene and styrene. The poly(1,2‐butadiene) segment was hydroborated and the hydroxy‐functions converted by a polymeranalogous reaction with the azo chromophore as side groups. The block copolymers were synthesized with different compositions by varying the length of the polystyrene segment and the length of the functionalized segment in order to obtain different morphologies. In this paper, for the first time a comparison of the cis‐trans photo‐isomerization behavior and photoaddressing with respect to different morphologies of the block copolymers is presented. To complete the comparison, the corresponding homopolymer and a statistical copolymer were also synthesized and investigated. A different photoaddressing behavior between homopolymer, statistical copolymer and the block copolymers was observed. One principal difference and advantage for photo addressable block copolymers is the lack of a formation of surface gratings which occurs in homopolymers and statistical copolymers.TEM of a poly(1,2‐butadiene)‐block‐polystyrene copolymer containing azobenzene side‐groups.magnified imageTEM of a poly(1,2‐butadiene)‐block‐polystyrene copolymer containing azobenzene side‐groups.

show abstract

A simplified procedure of anionic polymerization of styrene and dienes using 4,5-methylenephenanthrene as an indicator

Cited by 12 publications

References 5 publications

Holographic Gratings in Diblock Copolymers with Azobenzene and Mesogenic Side Groups in the Photoaddressable Dispersed Phase

Holographic Gratings in Diblock Copolymers with Azobenzene and Mesogenic Side Groups in the Photoaddressable Dispersed Phase

Linear‐Hyperbranched Amphiphilic AB Diblock Copolymers Based on Polystyrene and Hyperbranched Polyglycerol

Diblock Copolymers with Azobenzene Side‐Groups and Polystyrene Matrix: Synthesis, Characterization and Photoaddressing

Contact Info

Product

Resources

About