Hyperbranched photo responsive and liquid crystalline azo‐siloxane polymers synthesized by click chemistry

Three new types of hyperbranched photoactive liquid crystalline siloxane polymers containing azo moieties were synthesized using click chemistry methodology. The polymers were soluble in most of the polar solvents like chloroform, tetrahydrofuran, dimethylformamide, dimethyl sulphoxide and dichloromethane. The molecular weights of the polymers were in the range of 9000–12,000 g mol^?1. The trans‐cis photoisomerization of the polymer were studied both under UV radiation and dark. The isomerization rate constants were found to be in the range of 0.7–1.4 × 10^?2 sec^?1 and 7.0 × ?2.5 × 10^?5 sec^?1. The thermotropic behavior of the polymers was studied by using polarizing optical microscopy and differential scanning calorimetry, respectively. The polymers P1 and P2 showed liquid crystalline texture characteristic of nematic phase. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Photo and electrically switchable behavior of azobenzene containing pendant bent‐core liquid crystalline polymers

New class of photo and electrically switchable azobenzene containing pendant bent‐core liquid crystalline monomers ( AZBM 1, 2 , and 3 ) and their polymers ( AZBP 1, 2 , and 3 ) are reported. The synthesized precursors, monomers, and polymers were characterized by FT‐IR, ¹H, and ¹³C NMR spectroscopy. Thermal stability of polymers was examined by thermogravimetric analysis and revealed stable up to 260 °C. The mesophase transition of monomers and polymers are observed through polarized optical microscopy (POM) and further confirmed by differential scanning calorimetry (DSC). The electrically switching property of monomers and their polymers were studied by electro‐optical method. Among the three monomers AZBM 1, 2 , and 3 , AZBM 1 and 2 exhibit antiferroelectric (AF) switching and AZBM 3 exhibits ferroelectric (F) switching behavior. On the other hand, low molecular weight polymers ( AZMP 1, 2 , and 3 ) show weak AF and F switching behavior. The photo‐switching properties of bent‐core azo polymers are investigated using UV‐vis spectroscopy, trans to cis isomerization occurs around 25 s for AZBP‐1 and 30 s for AZBP‐2 and 3 in chloroform, whereas reverse processes take place around 80 and 90 s. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Nonisothermal crystallization kinetics of poly (phenylene sulphide) in composites with a liquid crystalline polymer

The article deals with the melting and nonisothermal crystallization behavior of neat poly (phenylene sulphide) (PPS) and its composites with a thermotropic liquid crystalline polymer (TLCP)—Vectra A950, prepared by melt mixing and probed by differential scanning calorimetry. The various macrokinetic models namely, the Ozawa, the modified Avrami, the Tobin, and the Mo models were applied to describe the crystallization kinetics under nonisothermal conditions. The kinetic crystallizabilty of PPS/TLCP composites calculated using the approach of Ziabicki varies depending on these two composite composition‐induced effects. Similarly Mo model predicts that to obtain a higher degree of crystallizabilty for PPS/TLCP composites, a higher cooling rate should be used. The effective energy barrier based on the differential isoconversional method of Friedman is found to be an increasing function of relative degree of melt conversion. The effect is explained in terms of nucleation theory proposed by Wunderlich to crystallization of polymers. The Lauritzen–Hoffman parameters are estimated using G = 1/t_0.5 effective activation energy equation proposed by Vyazovkin and Sbirrazzuoli. The K_g values estimated from latter equations are more comparable with values obtained using isothermal crystallization data than 1/t_0.5 method. Furthermore, the kinetic analysis using this equation shows a regime transition from regime II to regime III for 100/00, 90/10, 80/20 PPS/TLCP composites, basically attributed to reduced mobility of PPS chains in composites. This regime II to III transition is accompanied by a morphological transition from defective spherulitic sheaf‐like structures to ordered sheaf‐like structures. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1070–1100, 2010     

Synthesis and properties of mesogen‐jacketed liquid crystalline polymers containing bistolane mesogen

On the basis of the concept of mesogen‐jacketed liquid crystalline polymers, a series of new methacrylate monomers, (2,5‐bis[2‐(4′‐alkoxyphenyl) ethynyl] benzyl methacrylate (MACn, n = 4, 6, 8, 10, and 12) and 2,5‐bis[2‐(6′‐decanoxynaphthyl) ethynyl] benzyl methacrylate (MANC10), and their polymers, PMACn (n = 4, 6, 8, 10, and 12) and PMANC10 were synthesized. The bistolane mesogen with large π‐electron conjugation were side‐attached to the polymer backbone via short linkages. Various characterization techniques such as differential scanning calorimetry, wide‐angle X‐ray diffraction, and polarized light microscopy were used to study their mesomorphic phase behavior. The polymer PMACn with shorter flexible substituents (n = 4) forms the columnar nematic (?_N) phase, but other polymers with longer flexible tails (n = 6, 8, 10, and 12) can develop into a smetic A (S_A) phase instead of a ?_N phase. The PMANC10 containing naphthyl can also form a well‐defined S_A phase. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Synthesis and nonlinear optical properties of side chain liquid crystalline polymers containing azobenzene push–pull chromophores

Azobenzene monomeric precursors bearing piperazine as donor moiety with different withdrawing groups and derived side chain polymethacrylates have been prepared and characterized. Monomers having terminal cyano or nitro groups, and the corresponding polymers, exhibited smectic A phases. Linear and nonlinear optical properties of every monomer and thin films of the cyano polymer ( pol‐PZ‐CN ) have been also studied. UV‐vis spectroscopy revealed out‐of‐plane orientation in the as prepared films, as confirmed by waveguide refractive index measurements. Moreover, absorption spectra indicated the presence of azo aggregates in these films. The initial molecular arrangement has been modified by applying thermal annealing within the mesophase range and UV‐blue irradiation. Although thermal annealing resulted in a significant amplification of the out‐of‐plane optical anisotropy due to thermotropic self‐organization of side chain azo moieties, irradiation with 440 nm light induced some disruption of aggregates. The nonlinear optical response of Corona poled films has been studied by second harmonic generation measurements, and the influence of the molecular arrangement on the nonlinear d_ij coefficients has been analyzed. The more efficient poling corresponded to preirradiated films. In any case, a noticeable degree of polar order (70% of the initial d₃₃ value) remained for several months after the poling in films kept at RT. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 232–242, 2010     

Preparation and properties of novel thermotropic liquid crystalline hyperbranched polyesters composed of five‐membered heterocyclic mesogen by A2 + B3 approach

New thermotropic liquid crystalline (LC) hyperbranched (HB) polyesters containing 2,5‐diphenyl‐1,3,4‐thiadiazole (DTD) unit as mesogen in the interiors were prepared at various mole ratios (A₂/B₃) by melt and solution polycondensations of a dioxydiundecanol of DTD (A₂) and 1,2,3‐propanetricarboxylic acid (B₃) via the A₂ + B₃ approach and their LC and optical properties were investigated. FTIR and ¹H‐NMR spectroscopies indicated that all the expected HB polyesters, which show good solubilities in organic solvents, are produced without gelation during the polymerization. Among them, the HB polymer prepared in the mole ratio of A₂/B₃ = 3/2 by the solution polycondensation had the highest inherent viscositiy. DSC measurents, polarizing microscope observations of optical textures, and X‐ray analyses suggested that the LC properties of HB polymers depend on the polymerization methods and the feed mole ratios. In the HB polymers prepared using the melt polycondensation, only the polymer prepared in the mole ratio of A₂/B₃ = 3/1 formed a highly‐ordered, tilted, crystal‐like smectic phase, but all the polymers prepared by the solution polycondensation formed highly‐ordered, tilted, smectic phases. Solution and solid‐state UV‐vis and photoluminescent (PL) spectra indicated that the HB polymers show maximum absorbances and blue‐light emission on the basis of the DTD unit, where the Stokes‐shifts were observed, probably because of intermolecular aggregation effects © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2998–3008, 2007     

Synthesis and characterization of Y‐type polymers for second‐order nonlinear optical applications

A series of dicyanomethylene‐substituted polymers having Y‐type molecular architecture were synthesized by Knoevenagel condensation reaction. The polymers were found to be soluble in organic solvents like tetrahydrofuran and chloroform. From gel permeation chromatography, the molecular weights of the polymers were found to be in the range of 15,300–33,800 g/mol. Thermal analysis showed that the polymers were stable up to 350 °C with glass transition temperature (T_g) in the range of 129–212 °C. These polymers were found to form good optical quality films. The order parameter was calculated to be in the range of 0.01–0.48. Atomic force microscopy indicated prominent morphology changes due to alignment of dipoles after poling. By using Nd:YAG laser of 1064 nm, angular dependence and temperature dependence of second‐harmonic generation intensity were investigated. The geometry optimization, shape of polymers, and restricted torsion angle between acceptor and donor substituents (push–pull system) were calculated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Studies on curing kinetics of a novel combined liquid crystalline epoxy containing tetramethylbiphenyl and aromatic ester‐type mesogenic group with diaminodiphenylsulfone

The curing kinetics of a novel liquid crystalline epoxy resin with combining biphenyl and aromatic ester‐type mesogenic unit, diglycidyl ether of 4,4′‐bis(4‐hydroxybenzoyloxy)‐3,3′,5,5′‐tetramethyl biphenyl (DGE‐BHBTMBP), and the curing agent diaminodiphenylsulfone (DDS) was studied using the advanced isoconvensional method (AICM). DGE‐BHBTMBP/DDS curing system was investigated the curing behavior by means of differential scanning calorimetry (DSC) during isothermal and nonisothermal processes. Only one exothermal peak appeared in isothermal DSC curves. A variation of the effective activation energy with the extent of conversion was obtained by AICM. Three different curing stages were confirmed. In the initial curing stage, the value of E_a is dramatically decreased from ～90 to ～20 kJ/mol in the conversion region 0–0.2 for the formation of LC phase. In the middle stage, the value of E_a keeps about ～80 kJ/mol for cooperative effect of reaction mechanism and diffusion control. In the final stage, a significant increase of E_a from 84 to 136 kJ/mol could be caused by the mobility of longer polymer chains. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3922–3928, 2007     

Synthesis and characterization of fluorine-containing cholesteric liquid crystalline polysiloxanes bearing trifluoromethyl-substituted mesogens

A series of side-chain liquid crystal (LC) polysiloxanes were synthesised with Poly(methylhydrogeno)siloxane, 4?-(undec-10-enoyloxy) biphenyl – 4 – yl 4- (trifluoromethyl) benzoate (M_th) and a chiral nematic (N*) LC monomer 1-allyl 10-(cholesteryl)-decanedioate (M_ch). The chemical structures and LC properties of the monomers and polymers were characterised by FTIR, ¹H-NMR, differential scanning calorimetry, thermogravimetric analysis, POM and X-ray diffractometer. M_ch is monotropic N* LC. The homopolymer derived from monomer M_ch is enantiotropic N* LC. Monomer M_th is a smectic A liquid crystal. The copolymers derived from M_ch and M_th are N* LCs. The temperatures at which 5% weight loss occurred are greater than 300°C for all the fluoro-containing polymers, and the residue weights of the samples at 600°C increased slightly as the content of trifluoromethyl mesogens increased in the polymers. The glass transition temperatures of the polymers increased as trifluoromethyl mesogens increased, too. The N*–I phase transition temperatures show a negative deviate from ideal or linear behaviour. The values of the enthalpy changes for the cholesteryl containing polymers are rather low and this is attributed to the biaxiality of cholesteryl moiety which tends to reduce the change in the orientational order at the N*–I transition. Compared to the monomers, the polymers show wider mesophase region.     

Star polymers with POSS via azide–alkyne click reaction

Azidopropyl‐heptaisobutyl‐substituted polyhedral oligomeric silsesquioxane (POSS‐N₃) was reacted with 1,1,1‐tris[4‐(2‐propynyloxy)phenyl]‐ethane ( 1 ) and poly(ethylene glycol) (PEG)‐b‐poly(methyl methacrylate) (PMMA) copolymer with alkyne at its center (PEG‐PMMA‐alkyne) affording the first time synthesis of 3‐arm star POSS and PEG‐PMMA‐POSS 3‐miktoarm star terpolymer, respectively, in the presence of CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalyst and N,N‐dimethylformamide/tetrahydrofuran as solvent at room temperature. The precursors and the target star polymers were characterized comprehensively by ¹H NMR, GPC, and DSC. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5947–5953, 2009     

Synthesis and photoresponsive behavior of azobenzene‐containing side‐chain liquid crystalline diblock polymers with polypeptide block

Well‐defined azobenzene‐containing side‐chain liquid crystalline diblock copolymers composed of poly[6‐(4‐methoxy‐azobenzene‐4′‐oxy) hexyl methacrylate] (PMMAZO) and poly(γ‐benzyl‐L ‐glutamate) (PBLG) were synthesized by click reaction from alkyne‐ and azide‐functionalized homopolymers. The alkyne‐terminated PMMAZO homopolymers were synthesized by copper‐mediated atom transfer radical polymerization with a bromine‐containing alkyne bifunctional initiator, and the azido‐terminated PBLG homopolymers were synthesized by ring‐opening polymerization of γ‐benzyl‐L ‐glutamate‐N‐carboxyanhydride in DMF at room temperature using an amine‐containing azide initiator. The thermotropic phase behavior of PMMAZO‐b‐PBLG diblock copolymers in bulk were investigated using differential scanning calorimetry and polarized light microscopy. The PMMAZO‐b‐PBLG diblock copolymers exhibited a smectic phase and a nematic phase when the weight fraction of PMMAZO block was more than 50%. Photoisomerization behavior of PMMAZO‐b‐PBLG diblock copolymers and the corresponding PMMAZO homopolymers in solid film and in solution were investigated using UV–vis. In solution, trans–cis isomerization of diblock copolymers was slower than that of the corresponding PMMAZO homopolymers. These results may provide guidelines for the design of effective photoresponsive anisotropic materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Thermal and ionic‐conductive behaviors of liquid crystalline polymers with alkali metal salt

In order to investigate the relationship between ionic conductivity and liquid crystallinity, we prepared the main‐chain type polyester having 1,4‐bisstyrylbenzene units and ethyleneoxide chain in the repeating unit. The main‐chain type polyester with lithium salt at the ratio of 0.04 per polymer repeating unit exhibited a smectic phase. However, the polyester with lithium salt (0.11) showed a nematic phase. The ionic conductivity of the polyester with lithium salt increased with increasing lithium salt concentration. The trans‐type polyester exhibited a liquid crystalline phase, while the cis‐type polyester did not show any mesophase. We found that the ionic conductivity of the trans‐type polyester with lithium salt (0.11) was larger than that of the cis‐type polyester with lithium salt (0.11). However, a liquid crystalline phase was found in the side‐chain type polyether with alkoxy chain length of below 12. A smectic phase was induced for the non‐mesomorphic polyethers with lithium salt. The layer spacing of the smectic A phase for the non‐mesomorphic polyether with lithium salt decreased from 55 to 41 Å with increasing temperature. The ionic conductivity of the polyether with lithium salt increased with decreasing the layer spacing. Copyright © 2001 John Wiley & Sons, Ltd.     

Thermotropic liquid‐crystalline polymers containing five‐membered heterocyclic groups. X. Relationships between structures of semirigid polyesters based on three disubstituted 2,5‐diphenyl‐1,3,4‐thiadiazoles and thermotropic liquid‐crystalline and optical properties

Thermotropic liquid‐crystalline (LC) semirigid polyesters based on three terphenyl analogues of 1,3,4‐thiadiazole (2,5‐diphenyl‐1,3,4‐thiadiazole)s (DPTD) linking undecamethyleneoxy chain at different substituted positions were synthesized from three disubstituted (4,4′‐, 3,4′‐, and 3,3′‐) dioxydiundecanols of DPTD and four diesters, and the relationships between polymer structures and LC and optical properties were investigated. DSC measurements, texture observations, and wide‐angle X‐ray analyses revealed that the polymers composed of DPTD moiety having a more linear molecular structure and 1,4‐phenylene unit or short aliphatic chain tend to exhibit LC smectic C and/or A phases. The following observations were made: (1) the emergence of smectic C and/or A phases in all the polymers on the basis of 4,4′‐disubstituted DPTD, (2) formation of enantiotropic smectic C and/or A phases in the polymers containing a 1,4‐phenylene unit in the main chain, (3) formation of a more stable smectic C phase in the polymers having a short aliphatic [(CH₂)₄] chain, and (4) a decrease of the mesomorphic property of the polyesters in the order of 4,4′‐DPTD > 3,4′‐DPTD > 3,3′‐DPTD. Solution and solid‐state ultraviolet–visible and photoluminescent spectra indicated that all the polyesters display maximum absorbances and blue emissions arising from the DPTD moiety, whose peak maxima were shifted to lower wavelengths in the order of 4,4′‐DPTD > 3,4′‐DPTD > 3,3′‐DPTD as well as the aforementioned LC property. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2676–2687, 2003     

Liquid‐crystalline organic–inorganic hybrid polymers with functionalized silsesquioxanes

Liquid‐crystalline (LC) hybrid polymers with functionalized silsesquioxanes with various proportions of LC monomer were synthesized by the reaction of polyhedral oligomeric silsesquioxane (POSS) macromonomer with methacrylate monomer having an LC moiety under common free‐radical conditions. The obtained LC hybrid polymers were soluble in common solvents such as tetrahydrofuran, toluene, and chloroform, and their structures were characterized with Fourier transform infrared, ¹H NMR, and ²⁹Si NMR. The thermal stability of the hybrid polymers was increased with an increasing ratio of POSS moieties as the inorganic part. Because of the steric hindrance caused by the bulkiness of the POSS macromonomer, the number‐average molecular weight of the hybrid polymers gradually decreased as the molar percentage of POSS in the feed increased. Their liquid crystallinities were very dependent on the POSS segments of the hybrid polymers behaving as hard, compact components. The hybrid polymer with 90 mol % LC moiety (Cube‐LC90) showed liquid crystallinity, larger glass‐transition temperatures, and better stability with respect to the LC homopolymer. The results of differential scanning calorimetry and optical polarizing microscopy showed that Cube‐LC90 had a smectic‐mesophase‐like fine‐grained texture. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4035–4043, 2001     

Synthesis and characterization of poly(ethylene glycol) polymers functionalized by terminal tributyltin carboxylate moieties

Novel polymeric derivatives of various average molecular weights bearing tributyltin carboxylate moieties as terminal groups have been prepared by esterification with bis(tributyltin) oxide of the corresponding poly(ethylene glycol)s functionalized with dimethylenecarboxylic end groups. Low‐molecular‐weight compounds have also been synthesized, with the aim of investigating the influence of the polymeric chain on tin properties. As investigated by Sn NMR and Fourier transform infrared, the metal center appears to be completely tetracoordinated in chloroform solution at room temperature, whereas at low temperature, the tin atom undergoes a fast exchange between intramolecular pentacoordination with the ethereal oxygen atoms and the unassociated form. In the solid state, even at room temperature, all the polymeric products exhibit both tetracoordination and pentacoordination at tin, the latter achieved by interaction with both ethereal and carbonyl oxygens. The thermal behavior of the series of compounds indicates the presence of crystalline domains in the material, which can be ascribed either to intermolecular interactions at tin, giving rise to organometal aggregates, or to the formation of an ordered phase induced by the presence of the macromolecular chain, depending on the more or less elevated relative concentration of the organotin moieties in the sample. These findings are also confirmed by the X‐ray diffractions patterns of the investigated products. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3091–3104, 2005     

Photoresponsive poly(methyl methacrylate)‐b‐azodendron block copolymers prepared by ATRP and click chemistry

A range of block copolymers (BCs) consisting of a linear poly(methyl methacrylate) (PMMA) block linked to an aliphatic polyester dendron functionalized with azobenzene moieties have been synthesized by sequential atom transfer radical polymerization (ATRP) and Click Chemistry. Two alkyne‐functionalized PMMA homopolymers with different molecular weights were obtained by ATRP and coupled to generations 2 to 4 of azodendrons bearing an azide group at the focal points. In the case of the azodendron with the highest generation number, the length of the flexible spacer attaching the cyanoazobenzene units to the dendron has also been modified. The coupling of both blocks and purity of BCs were checked by gel permeation chromatography, nuclear magnetic resonance, and infrared spectroscopy. The thermal transitions and liquid crystalline behavior of the BCs were investigated by differential scanning calorimetry and polarized‐light optical microscopy. A morphological study was carried out by transmission electron microscopy, using samples annealed at 115 °C. Photo‐induced anisotropy was induced in thin films of these materials after annealed at 115 °C. The highest stable birefringence values were obtained for the BCs bearing 8 and 16 azobenzene units in the dendritic block. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1538–1550, 2010     

Synthesis of new Azo‐based liquid crystalline polymers and their selective sensing behaviors to alkali metal ions

We report novel liquid crystalline (LC) polymers containing pendant azobenzene moieties with n‐dodecyl substituents and ethyleneoxy spacers of different lengths and describe their selective detection behaviors to alkali metal ions. The new azopolymers produce homogenous smectic phases with a typical fan‐shaped texture. UV‐Vis and ¹H NMR studies confirm that the azopolymers selectively bind to Li⁺ and Na⁺, but do not complex with K⁺, Ba²⁺, Mg²⁺, or Ca²⁺. Both the ethyleneoxy spacer and azobenzene units participate in binding to Li⁺ and Na⁺ cations in solution. Interestingly, after formation of the complexed structure, the ratio of cis to trans conformer is considerably increased suggesting stronger interactions of the cis conformer with alkali metal ions. Irradiation of the complexed structure with 365 nm UV induces conversion of the uncomplexed trans to the cis. These findings suggest a great potential of the LC azopolymers as selective sensors or separation membranes for alkali metal ions. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1713–1723     

Synthesis and phase behavior of side‐chain liquid‐crystalline polymers containing malachite green lactone groups

New side‐chain liquid‐crystalline polymers containing both cholesteric and thermochromic side groups were synthesized. Their chemical structures were confirmed with elemental analyses and Fourier transform infrared, proton nuclear magnetic resonance, and carbon‐13 nuclear magnetic resonance spectra. The mesogenic properties and phase behavior were investigated with differential scanning calorimetry, thermogravimetric analysis, polarizing optical microscopy, and X‐ray diffraction measurements. The effect of the concentration of dye side groups on the phase behavior of the polymers was examined. The polymers showed smectic or cholesteric phases. Those polymers containing less than 20 mol % dye groups had good solubility, reversible phase transitions, wider mesophase temperature ranges, and higher thermal stability. The experimental results demonstrated that the isotropization temperature and mesophase temperature ranges decreased with an increasing concentration of dye groups. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3870–3878, 2004     

Side chain liquid crystal poly(fumarate)s bearing tolane‐based mesogens

Cyanotolane or fluorotolane mesogens were for the first time introduced into the fumarate monomer under basic conditions. All fumarate monomers undergo radical polymerization in benzene in the presence of dimethyl 2,2′‐azobis(isobutyrate) as an initiator at 60 °C, affording the corresponding poly(fumarate)s with a molecular weight (M_n) of ～ 10⁴ and an exceptionally narrow polydispersity. The phase behaviors of the fumarate monomers and the correspoding poly(fumarate)s were comprehensively investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and X‐ray diffraction (XRD) analysis. For the fumarate monomers, fluorotolane derivatives were prone to form higher‐order liquid crystal phases such as a smectic phase, while cyanotolane derivatives tended to show a wide mesophase temperature range, depending on the alkyl chain spacer length. Very surprisingly, these features dramatically weakened when they were polymerized. The mesophase temperature ranges became narrow and completely disappeared for the poly(fumarate)s with a shorter alkyl chain spacer. A nematic phase representing lower‐order arrangements became a predominant liquid crystal phase for the poly(fumarate) carrying cyanotolane mesogens. Only the poly(fumarate) carrying fluorotolane mesogens with a longer alkyl chain spacer displayed the characteristic XRD patterns of the smectic B phase. The transient photocurrent measurements of the fumarate monomer with cyanotolane mesogens displayed a hole mobility of the order of 10^?4–10^?5 cm² V^?1 s^?1 at room temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5101–5114, 2008