Solid State Polymerization Of Diacetylenes Research Articles

Synthesis and Solid-State Polymerization of Diacetylene with Tetrathiafulvalene and the Electronic Properties

We synthesized a new diacetylene monomer with urethane groups in the middle of the substituents and tetrathiafulvalene (TTF) moieties at both ends (BT). BT was found to form the CT complex with tetrafluorotetracyanoquinodimethane (F4TCNQ) to be (BT)(F4TCNQ)2. BT could be polymerized in the solid state to give irregular conjugated structure by UV irradiation although the solid-state polymerization of the CT complex was not confirmed. Morphology of their cast films was observed by AFM. The films of (BT)(F4TCNQ)2 before and after UV irradiation showed semiconducting temperature dependence with activation energies of 0.19 and 0.16 eV, respectively, and the electrical conductivities at room temperature were found to be more than 10−5 Scm−1.

Solid State Polymerization of Diacetylenes with Amide Groups

Two diacetylene derivatives (1, 2) carrying amide groups were prepared in order to control their packing arrangements by intermolecular hydrogen bonds. 1, 6-Bis(4-acetamidomethylphenoxy)-2,4-hexadiyne 1 is a symmetric diamide, which showed no changes by annealing. p-N-acetyl(6-hydroxy-2,4-hexadiynenyloxy)benzylamine 2 with amide and alcohol groups showed photo and thermal reactivity. Compound 2 crystallized in the monoclinic P21/c space group with a = 17.9162(3) A˚, b = 4.8646(2) A˚, c = 16.106(3) A˚, β = 105.19(1)°. The molecules stacked one-dimensionally along the b axis and the intermolecular hydrogen bonds of the amide groups ran along the stacking axis. The hydroxyl group in the other end of the structure of 2 was also involved in polymeric hydrogen bonds, which also appear to play an important role in the molecular arrangement.

Monte-Carlo simulations of chemical reactions in molecular crystals

Chemical reactions in molecular crystals, yielding new entities (dimers, trimers,…, polymers) in the original structure, are simulated for the first time by stochastic Monte Carlo methods. The results are compared with those obtained by deterministic methods. They show that numerical simulation is a tool for understanding the evolution of these mixed systems. They are in kinetic and not in thermodynamic control. Reactive site distributions, x-ray diffuse scattering, and chain length distributions can be simulated. Comparisons are made with deterministic models and experimental results obtained in the case of the solid state dimerization of cinnamic acid in the beta phase and in the case of the solid state polymerization of diacetylenes.

Polydiacetylenes Having Quinolyl Sidegroups for Third-order Nonlinear Optical Materials

The solid-state polymerization of diacetylenes (DAs) [1, 2] to polydiacetylenes (PDAs) has long been investigated to obtain materials for photonics. PDA, being a quasi-one-dimensional ð-conjugated system, shows non-linear optical (NLO) properties as well as important chromic properties arising due to conjugated systems [3±5]. However, due to our limited knowledge of the physics and chemistry of DA polymerization and the relationship of polymer structure with the NLO properties, it is not easy to design a perfect DA, which on polymerization should yield PDA with all the expected properties. In our laboratory, we have been preparing DAs with an aim to get good third-order NLO materials [6]. One class of DAs, which we have been investigating, consists of heteroaryl moieties directly bound to the DA stem [7]. Here, we report a series of quinoline-containing novel DAs that topochemically polymerize to give PDAs, 1.

Theoretical Investigation on the Topochemical Polymerization of Diacetylenes

Abstract The solid-state polymerization of diacetylenes (MDA-PBT-PDA) is studied with a concerted reaction model and the calculation method of EHMO-ASED and EHCO-ASED, where MDA = crystalline molecular diacetylenes, PBT = polybutatrienes, and PDA = polydiacetylenes. As the reaction goes on, the symmetry of frontier orbitals inverts at state PBT, HOCO from C 2-antisymmetry to C 2-symmetry and LUCO from C 2-symmetry to C 2-antisymmetry, which means completion of the 1,4-addition. Two necessary conditions must be satisfied for the reaction to take place: 1) the geometric parameters must undergo a series of concerted changes to make the conformation suitable for the intermolecular 1,4-addition, which should overcome an energy barrier Eb ; 2) the symmetry match between the frontier crystal orbitals of the reactant and the product must be satisfied-electrons of the reactant should be excited from HOCO (C 2-antisymmetry) into LUCO (C 2-symmetry), which faces an energy gap E g. At state MDA, there is E g(MDA) ≈ 5...

Solid state polymerization of diacetylenes

Solid state polymerization of diacetylenes

Solid State polymerization of diacetylenes 4*. Crystal and molecular structure of l,4-bis(1-oxyl-2,2,6,6-tetrainethyl-∆3-dehydropiperidine-4-yl)butadiyne

Solid State polymerization of diacetylenes 4*. Crystal and molecular structure of l,4-bis(1-oxyl-2,2,6,6-tetrainethyl-∆3-dehydropiperidine-4-yl)butadiyne

Solid State polymerization of diacetylenes 3.* Crystal and molecular structure of 1,4-bis( 1 -oxyl-2,2,6,6-tetramethyl-4-hydroxy-piperidine- 4-yl)butadiyne

Solid State polymerization of diacetylenes 3.* Crystal and molecular structure of 1,4-bis( 1 -oxyl-2,2,6,6-tetramethyl-4-hydroxy-piperidine- 4-yl)butadiyne

Solid state polymerization of diacetylenes

An X-ray structural study (R = 0.040 for 1871 reflections) of the title compound has been carried out. Molecules in crystal are pseudocentrosymmetric, the piperidine cycle is in a chair conformation. The N atoms of both paramagnetic centers exhibit, in fact, the same degree of pyramidalization, their displacements from the planes of their bonded atoms being 0.111 and 0.119(2) Å. In crystal the molecules form two sets of infinite ribbons (along the [112] and [[unk]12] directions), which are linked with each other via the O – H … O hydrogen bonds along the [001] direction. Although the packing of diacetylene rod-like groups does not correspond to the conditions of topochemical polymerization of diacetylenes, compound I polymerizes in crystal.

Solid state polymerization of diacetylenes

An X-ray structural study of 1,8-bismethacryloyloxyoctadiyne-3,5 ( I ) ( R = 0.051 for 967 reflections) has been carried out. Infinite ribbons of molecules related by the b = 4.5340(4) Å translation can be distinguished in the crystal. The relative orientation of molecules does not permit their topochemical interaction via either shearing mechanism in ribbons involving the triple bonds or four-center polymerization involving the terminal double bonds.

Solid state polymerization of diacetylenes

An X-ray structural study (R = 0.043 for 2704 reflections) of C24H30N2O4 was carried out. The molecule has a skewed conformation, the piperidine cycles are in a chair conformation. The N atoms of paramagnetic groups exhibit different degrees of pyramidalization, due to crystal packing effects, their displacements from the planes of three bonded atoms being 0.111 and 0.042(2) Å. The H-bonds of the O – H … O type link the molecules into layers parallel to the ac-plane. The molecules do not form characteristic stacking necessary for the topochemical solid state polymerization. This fact is in good agreement with the observed inertness of the crystals with respect to the solid state polymerization.

Topochemistry of the solid-state polymerization of diacetylenes containing unsaturated side groups

The electronic spectra of polymers in the monomer matrix have been investigated for two structurally similar diacetylenes one of which has side substituents containing the allyl bond which is responsible for degradative chain transfer in the case of liquid-phase polymerization. Melting points and phase transition temperatures were determined for the monomers and polymers by the DSC method. A study of the integral absorption of the polymers in the visible portion of the spectrum shows that the photopolymerization rate for the diacetylene containing the allyl double bond is only one-third of that for the diacetylene that is without the allyl bond. This fact is attributed to a high degree of topotacticity of the solid-state polymerization of crystalline diacetylenes.

The solid state polymerization of diacetylenes

The solid state polymerization of diacetylenes

The solid state polymerization of diacetylenes

An X-ray study of 2,4-hexadiyne-1,6-di(p – n-hexyloxy)benzoate was carried out (R = 0.060 for 3223 reflections). The molecule has a skew conformation with the pseudotorsion angle relative to the linear diacetylene moiety equal to −110.0(9)°. The non-ability to polymerization in solid state of the studied diacetylene is explained on the basis of crystal chemistry criteria. Cell parameters of two nearest homologues of the studied compound are determined (for one of them on a polymeric state).

Solid state polymerization of diacetylenes

Solid state polymerization of diacetylenes

Solid-state polymerization of diacetylenes

Solid-state polymerization of diacetylenes

Quantum yield of solid state polymerization of diacetylenes

Chemical actinometry was used to make the first reliable determination of the quantum yield of the solid state polymerization of two diacetylenes RCCCCR, the first compound being 5,7-dodecadiyn-1,12-bis( n-butoxycarbonylmethylene urethane) (4BCMU) where R  (CH 2) 4-OCONHCH 2COO(CH 2) 3CH 3 and the second being 2,4-hexadiyn-1,6-bis( p-toluenesulfonate) (1 pTS) where ▪. The number of monomer molecules polymerized on irradiation at 254 nm was determined by absorption spectroscopy. A quantum yield of above 50 was observed for 4BCMU while 1 pTS gave the much lower value of 0.06 ± 0.03. The lower quantum yield for 1 pTS is explained by the low molecular weight chains provided by polymerization.

Structure-Reactivity Relationships in the Solid State Polymerization of Diacetylenes

Abstract Many diacetylenes undergo 1,4-addition polymerization in the solid state. In the course of our work we have discovered several examples in which seemingly minor changes in the constitution of highly reactive monomeric diacetylenes have rendered them inert. The subtlety of the effects, revealed by structural studies, illustrates the stringent packing requirements for solid state polymerization.

Solid-state polymerization of diacetylenes

Differences in the solid-state reactivity of two substituted diacetylenes with identical lattice symmetry (P21/c) are described in terms of the molecular rotational and translational motion necessary for 1,4-addition polymerization. The structural relationship between monomer and polymer has been investigated in detail for the solid-state polymerization of 2,4-hexadiynediol. For the thermal, uv, or γ-ray-induced polymerization of this monomer the same crystallographic relationship was found between the polymer chain direction and the monomer lattice. Mutually reacting monomer molecules are related by a unit-cell translation along the a/c diagonal, which is perpendicular to the unique axis of this monoclinic crystal. X-ray diffraction determination of unit-cell parameters for γ-ray-irradiated samples of differing conversion have confirmed that the polymer enters the monomer lattice as a solid solution and verify the mentioned polymerization mechanism. When these irradiated samples were thermally annealed, phase separation occurred, producing discrete monomer and amorphous polymer phases. Despite the instability of the partially polymerized 2,4-hexadiynediol lattice, ir measurements reveal no free hydroxyl hydrogens either before or after phase separation. Neighboring monomer molecules are indirectly hydrogen bonded together in the c-axis direction, but no hydrogen bonding exists between mutually reacting monomer molecules in disagreement with a previously suggested model for lattice-controlled diacetylene polymerizations. During the polymerization of 2,4-hexadiynediol the center-to-center separation of mutually reacting molecules must change by − 0.44 Å and the conjugated molecular rods must rotate by an angle of at least 28°. This large required molecular rotation suggests that the activation energy for rotation contributes significantly to the activation energy for polymerization. The high entropy of fusion (17.0±1.2 eu) measured for this compound is consistent with low solid-state rotational mobility. No solid-state phase transitions were observed calorimetrically for 2,4-hexadiynediol from − 100°C to the melting point (114.5±0.3°C). The low solid-state reactivity observed for diphenyldiacetylene is reasonable in light of the much larger translation and rotation necessary for 1,4-addition polymerization, respectively, − 1.14 Å and 37.5°. No ethanol insoluble polymer was obtained for γ-ray radiation dosages which resulted in high monomer-to-polymer conversions for 2,4-hexadiynediol. No measurable difference was observed in the melting behavior of γ-ray-irradiated and nonirradiated samples of this high entropy of fusion compound (14.1±0.7 eu).