Liquid‐crystalline polysulfones, 1. Copolymers of 1‐alkenes with sulfur dioxide

Braun, D.; Herr, Rolf‐Peter; Arnold, Norbert

doi:10.1002/marc.1987.030080708

Cited by 24 publications

(5 citation statements)

References 7 publications

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“…4-((Benzyloxycarbonyl)oxy)benzoic acid (7) was synthesized according to the literature. 18 1-Chloro-6-(vinyloxy)hexane (6). A mixture of 29.9 g (219 mmol) of 4, 157.0 g (1580 mmol) of 5, and 11.7 g (37.0 mmol) of mercuric acetate was refluxed under stirring for 6 h, and then 15 g of dry potassium carbonate was added.…”

Section: Methodsmentioning

confidence: 99%

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Laus¹,

Bignozzi²,

Fagnani³

et al. 1996

Macromolecules

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A series of liquid crystalline (LC) poly(vinyl ether)s 1 was prepared by living cationic polymerization of a mesogenic vinyl ether monomer, 4-butoxyphenyl 4-((6-vinylhexyl)oxy)benzoate (11), in the presence of the HI/I2 (1/1 mol/mol) initiating system. The number average molar mass of polymers 1 increased linearly with the initial monomer to initiator molar ratio (M n = 3000−15 000 g mol-1, DPn ≈ 5−50), according to the living character of the polymerization, and their molar mass distribution was rather narrow (M w/M n = 1.10−1.15). Furthermore, two sets of AB diblock copoly(vinyl ether)s 2 and 3 were prepared by sequential polymerization of vinyl ether 11 and isobutyl vinyl ether (12) and chiral (S)-2-methylbutyl vinyl ether (13) respectively, by using the same HI/I2 system. While the average degree of polymerization of the LC block was kept constant (DPn ≈ 10), the length of the non-LC block was varied (DPn ≈ 2−25), according to the chosen feed conditions. An X-ray investigation proved that polymers 1 gave rise to a sequence of ordered smectic (F or I), smectic C, and nematic mesophases with increasing temperature. Their transition temperatures and entropies followed slightly different molar mass dependences, but each of them reached a saturation value at M n ≈ 6000 g mol-1. The same basic mesophase polymorphism was also observed for the LC block copolymers 2 and 3, thus suggesting that the chemically different blocks were microphase separated within the solid and LC phases.

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Section: Methodsmentioning

confidence: 99%

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Laus¹,

Bignozzi²,

Fagnani³

et al. 1996

Macromolecules

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“…Yield: 19,3 g (64%) hygroscopic colourless powder, mp = 132°C C,,jH,,NO,S 319,51 Calc. C 60,15 H 1441 N4,38 S 10.04 Found C 60,16 H 7,95 N 4,42 S 10,30 'H NMR (400 MHz, CDCI,): 6 (in ppm) = 1,2-1,4 (m; 14H, -(CHd7-), 1,67 (m; 2H, -CH2-C-N+-), 2,Ol (m; 2H, C=C-CH,-), 2.18 (m; 2H, -N+-C-CH2-C-S03), 2,86 (t; 2H, -CH,-SO,), 3,16 (s;6H,2), 3,24 (m; 2H, -CH2-N+), 3,64 (m; 2H, -N+-CH,-C-C-SO,), 4,50 (m;2H,5,78 (m;1 H,. N-methyl-N-(10-undecenoy1)piperazine: 4 g (0,04 mol) of 1-methylpiperazine and 7,l g (0,039 mol) of 10-undecenoic acid are refluxed in 100 mL of toluene for 3 days.…”

Section: Methodsmentioning

confidence: 99%

Polysoaps via alternating olefin/SO₂ copolymers

Anton

Laschewsky

1991

Makromol. Chem., Rapid Commun.

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“…In this investigation we report the self-ordering properties of thin films of several poly(olefin sulfone)s, polymers that are readily prepared by the free radical polymerization of alkenes and sulfur dioxide and have an alternating structure −(CH 2 −CHR−SO 2 ) n − . Liquid crystallinity has been found not only in those polysulfones that bear a conventional calamitic mesogenic group in the side chain − but also in those with merely a long paraffinic side chain. , In the latter case the ordering structure is the backbone itself, which despite being atactic as made by the free radical copolymerization of SO 2 with an olefin , adopts a helical configuration. Strong electrostatic interaction between each pair of sulfone dipoles ,− locks the intervening three backbone bonds into a rather stable configuration.…”

Section: Introductionmentioning

confidence: 99%

Self-Ordering within Thin Films of Poly(olefin sulfone)s

et al. 1998

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A study has been performed of the manner in which two structural features of poly(olefin sulfone)s, helical backbones and calamitic side chains, create order in films. For this purpose copolymers were prepared with one (polymer I) or two (polymer III) cyanobiphenyls per residue, and terpolymers were prepared with both such residues diluted to below the 5% level within an otherwise poly(eicosene sulfone) chain (respectively, polymers II and IV). The polymers all have ordered phases according to X-ray powder diffraction studies on samples cooled from the melt, a layer spacing of about 45 Å being detected in the films as in the bulk. Those polymers with mainly eicosene sulfone residues had crystalline phases with large domains, the layers deriving from the helical backbones alone, the smectic A phases of the parent poly(eicosene sulfone) being either suppressed or reduced in extent by the presence of the aromatic moieties, which were almost randomly orientated. Those with one or two cyanobiphenyls per residue were liquid crystalline. In the latter the layer spacing derives from both backbone and side chains and is reduced when the residues bear a second mesogen as a consequence of a constraining effect from the stiff backbone, as a novel model predicts. The spacers give rise to a glass transition and segregate the planes in which the stiff backbones are assembled from the regions in which the aromatic groups aggregate on account of the strong pi-pi interactions. Amorphous and optically isotropic spun cast films of these polymers became ordered on cooling from the melt or just on annealing, with the order, as determined by studies on the optical properties, being homeotropic for the aromatics and being planar for the backbones in a monodomain. For this arrangement we introduce the term homeo-planar smectic. Order parameters as high as 0.63 were measured for polymer I, from a clear film. The cyanobiphenyl chromophores formed H aggregates, with blue shifts in absorption and red shifts in fluoresence, and a little surprisingly these resulted in a circular dichroism, detectable when the films were inspected at an angle of 45 degrees to the normal.

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Liquid‐crystalline polysulfones, 1. Copolymers of 1‐alkenes with sulfur dioxide

Cited by 24 publications

References 7 publications

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Polysoaps via alternating olefin/SO₂ copolymers

Self-Ordering within Thin Films of Poly(olefin sulfone)s

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Liquid‐crystalline polysulfones, 1. Copolymers of 1‐alkenes with sulfur dioxide

Cited by 24 publications

References 7 publications

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Liquid Crystalline Poly(vinyl ether)s and Block Copoly(vinyl ether)s by Living Cationic Polymerization

Polysoaps via alternating olefin/SO2 copolymers

Self-Ordering within Thin Films of Poly(olefin sulfone)s

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Polysoaps via alternating olefin/SO₂ copolymers