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Structure dependence of electrical properties was investigated for amorphous and epitaxial thin films of chloroaluminumphthalocyanine vacuum deposited on both glass and KCl. The extrinsic conductivity in the dark was improved by elevating substrate temperatures, depending on the morphological change from granular, discontinuous films deposited at a substrate temperature of 25 °C to uniform, continuous ones at 250 °C. The photocurrents under monochromatic light illumination increased in proportion to the amount of adsorbed O2 in the amorphous films on glass. A regular doping form of O2 in the epitaxial film on KCl could enhance photocarrier generation. The granular, discontinuous morphology in the films caused a frequent charge‐carrier recombination at the grain boundaries and defect sites. In the intrinsic region the amorphous films exhibited a higher dark conductivity due to the π‐electron interaction between the randomly arranged molecules and gave a moderate activation energy for conduction. The epitaxial film with a regular orientation exhibited a significantly higher activation energy for intrinsic dark conduction because of a weak molecular interaction between the standing molecular columns.

Dynamic moduli, E′ and E″, and loss tangent tan δ were investigated for thermoplastic elastomers (TPEs), styrene-isoprene-styrene copolymers (SISs), styrene-butadiene-styrene copolymer (SBS), and Hytrel and composites reinforced by poly(ethylene terephthalate) (PET) short fibers. The styrenic TPEs have a typical rubbery behavior and the Hytrel TPE has medial characteristics between rubber and plastic. Both E′ and E″ of the composites depended on the matrix as well as the fiber loading and fiber length. Based on the viewpoint of different extensibility between the fiber and the matrix elastomer, a triblock model was considered for estimating the storage modulus of the short fiber-TPE composites as follows: Ec = αVfEf + β (1 − Vf) Em, where α and β are the effective deformation coefficients for the fiber and the matrix elastomer, respectively. They can be quantitatively represented by modulus ratio M (= Em/Ef) and fiber length L: α = ( Ln + k) M/ ( LnM + k), β = (1 − α Vf)/ (1 − Vf), where the constants n and k are obtained experimentally. When k = 0.022 and n = 0.45, Ec of the TPE composites agreed well with the prediction of the proposed model. The relaxation spectrum of the composites showed a distinct main peak ascribed to the matrix elastomer, but no peak to the PET fiber. The relative damping of main relaxation, (tan δmax)c/(tan δmax)m, decreased monotonously with increasing fiber loading and fiber length and with decreasing modulus of matrix elastomer. Thus, the relative damping may be attributed not only to the volume effect of matrix, but also to the unevenness of the strain distribution in the matrix phase, which depends on the fiber length and the matrix's modulus. The findings prove that the different extensibility between fiber and matrix and the uneven distribution of strain in matrix were important for the short-fiber reinforcement of the TPE composites. © 1993 John Wiley & Sons, Inc.

Presented in this paper is the investigation of the mechanical properties of PET short fiber-polyester thermoplastic elastomer (Hytrel) composites and the discussion of the short fiber reinforcement of the composites. Excellent adhesion of PET fiber to Hytrel elastomer was obtained by treating with isocyanate in toluene solution. The Hytrel composites filled with treated fiber showed a similar tensile behavior, with higher values, to that for the matrix elastomer when fiber loading was less than 5 vol %. The composites loading fibers more than 5 vol % displayed an obvious yield phenomenon, and their yield elongation (between 30–40%) was greater than the fiber's break elongation, which suggested that extensibility of the fiber was quite different from that of the matrix. It is considered that the reinforcement of the short fiber mainly depends on the difference of extensibility between the fiber and the matrix because the difference directly affects the effective transference of the stress from matrix to fiber. The modified parallel model for Young's modulus and yield strength of the composite can be given by the following equations: and respectively, through introducing two effective deformation coefficients, α and β, to represent the extensibility of the fiber and the matrix respectively. The α obtained from the experimental results did not depend on fiber loading but increased with increasing fiber length, and the α for Young's modulus was larger than the one for yield strength, which suggests that α is a function of the strain of the composite and may decrease with increasing the strain, namely, the deformation difference between the fiber and the matrix increases when the strain increases. On the other hand, β is a function of α as: For the Hytrel elastomer, the maximum of each succeeding stress–strain cycle coincided with the original stress–strain curve for elongations under 600%, but for the Hytrel composites such coincidence was limited to elongations under 30%. This may be caused by the reforming of crystallites in the stress-softened Hytrel elastomer phase at high strain. © 1993 John Wiley & Sons, Inc.

We have used scanning probe microscopy and transmission electron microscopy (TEM) to investigate the molecular orientation of cobalt naphthalocyanine (CoNc) vacuum deposited onto a NaCl substrate. Atomic force microscopy observations taken on CoNc deposited at room temperature reveal mostly amorphous grains with only few regions showing columnar structure. For CoNc films deposited at 250 °C, scanning tunneling microscopy and TEM showed domains of columnar structure arranged in various orientation. The periodicity of the columnar structure was determined to be 1.5 and 0.34 nm from x‐ray and electron diffraction and indicates that the molecules are standing with their planes perpendicular to the underlying NaCl substrate surface.

4-(N,N-dimethylamino)-3-acetamidonitrobenzene (DAN) was evaporated onto a glass plate and a cleavage surface of KCl in vacuo. DAN films deposited on the glass plate were composed of randomly oriented laminate crystallites. The DAN film deposited on KCl substrate, on the other hand, was composed of tabular crystallites crossing orthogonally. The (001) plane of the DAN crystal lay parallel to the substrate surface, and its a axis oriented parallel to the 〈110〉 directions of the KCl substrate. The second harmonic (SH) intensities of DAN films were measured. When the film deposited on KCl substrate was rotated around an axis coinciding with the laser beam propagation direction, the SH intensities of the film changed periodically corresponding to the molecular configuration in the film. The biorientational order of DAN crystal observed by electron microscopy on KCl substrate was confirmed on a macroscopic scale by second harmonic generation.

Epitaxial thin films of naphthalocyanines (Nc’s) were prepared on the (001) surface of alkali halide (AX) by a vacuum‐deposition technique. Two types of molecular stacking and orientation were found depending on the molecular structure. Metal‐free Nc(H2Nc) and divalent zinc Nc(ZnNc) took the face‐to‐face, eclipsed stacking, P orientation, in which their molecular planes came into a parallel contact to the substrate surface. Trivalent chloroaluminum Nc(AlNcCl) and fluorogallium Nc(GaNcF), and tetravalent vanadyl Nc(VONc) took the eclipsed, slipped stacking, I orientation, holding their molecular planes slightly inclined to the substrate surface. In the latter orientation an unexpected face‐to‐face stacking caused a stacking defect structure. The tetragonal lattice of the Nc crystals demonstrated five types of commensurate matchings to the ionic lattice of AX, depending on the lattice parameters of the Nc and AX crystals. On NaCl unidirectional AX(001)(4×4)R+45°‐Nc was a predominant orientation, and on KCl ...

The denaturation of pseudomonas-cytochrome c 551 at the air-water interface was studied using scanning tunneling microscopy (STM). The STM images indicate that the native secondary and tertiary structures of this protein has been virtually lost at such interface. The polypeptide chains of the unfolded protein are nearly fully extended, and highly aggregated in a localized region, forming a crystalline or a twisted rope-like structure. Our observation demonstrates the capability of STM in studying the unfolding of proteins, and also suggests the possibility of using STM to directly sequence the amino acid residues of a protein.

5,10,15,20-tetra (4-pyridyl) porphyrin thin films were vacuum-evaporated onto a KCl (001) surface. The orientation of the thin film was investigated by electron microscopy, and X-ray and electron diffractions. The film was composed of crystallites which have orthorhombic lattice with dimensions of a = 2.12 nm, b = 0.68 nm, and c = 2.18 nm. The crystal grew epitaxially on a KCl (001) surface with its (001) plane parallel to the KCl (001) plane. A column structure observed by high-resolution electron microscopy showed molecules packed in thin crystals. The molecular planes of the porphyrin were oriented almost perpendicularly to the KCl (001) plane. The crystals grew along three different directions against the KCl direction, the angles between the column axis and the KCl [100] direction were 0°, 27°, and 45°.

1,4-Bis [β-pyridyl-(2)-vinyl] benzene (P2VB) grew epitaxially on a cleavage surface or KCl crystal from vapor phase. By photo-irradiation P2VB monomer in the film converted to poly-P2VB containing cyclobutane rings. The photopolymerization mechanism of P2VB film was discussed from the electron-microscopic observation

Epitaxial growth of 5,10,15,20-tetraphenylporphyrin metal complexes (MTPP; M = Zn, Mg, Co, VO) and their photoelectrochemical properties were investigated. MTPP crystals grew epitaxially on a KC1 (001) surface by a physical vapor deposition method. All the crystals belong to the tetragonal system. The (100) plane of MTPP crystals is parallel to the KC1 (001) plane, and the [100] axis is parallel to the KC1 (120) axis. Photoelectrochemical properties were measured in the indium-tin oxide(ITO)/MTPP/Ia-,I-/Pt system.

An orientation-controlled thin film of AlPcCl was prepared by vacuum deposition on a (001) surface of a KCl substrate. In the epitaxially grown film on KCl AlPcCl molecules stack cofacially, staggering around the Al-Cl-Al bonds and holding the molecular planes parallel to the KCl surface. At a low substrate temperature the deposit was a uniform and closely oriented thin film. As the substrate temperature increased, the film became rugged and cracked due to growth of a large size of crystallites

The electrochromism of (octacyanophthalocyaninato)metal-metal complex (MPc(CN) 8 -M, M=Cu,Co) films was investigated by in situ visible and Raman spectroscopies in 1M HCl and 0.1M KOH/1M KCl. A new absorption band was observed in the near-infrared region during electrochemical reduction in these electrolytes. In the CuPc(CN) 8 -Cu film, charges stored in the cathodic waves were 1.1 and 1.3 F/mol in the acid and alkaline electrolytes, respectively

ポリ乳酸はいわゆるポリエステルの1種で, 生分解性を持つポリマーである. 本実験では, 数平均分子量6.6×105のポリ乳酸を製膜し, このフィルムに紫外線照射し, 分解挙動を調べた. 紫外線照射開始後の15分経過で分子量は半分にまで下がり, 1時間経つと1/4となった. この低下は紫外光がポリマー鎖をランダムに切断したために起こった. 分解生成物のIR分析は, 空気または窒素気流中いずれの場合の照射でも, 3290cm-1近傍にカルボン酸の水酸基に帰属される吸収の増加を示した. この増加は, 主鎖切断により生成したカルボキシル基末端の生成によるものである. さらに照射時間に対するフィルム重量減少も測定され, 重量減少は, 窒素雰囲気より空気雰囲気での照射でより大きいことがわかった. 主鎖切断数, カルポキシル基量, 二重結合生成量は, 照射時間増加に対し, 直線的で, Norrish II型光分解であることがわかった.

2,5-Distyrylpyrazine (DSP) was vapor-deposited onto a surface of potassium chloride obtained by cleavage. The DSP films were composed of crystallites of two modifications, a photoactive α-form and a photostable γ-form, depending on the evaporation conditions. The former appeared as tabular and as laminate crystallites and the latter as needle-like ones. The electron diffraction pattern from the tabular and the laminate crystallites showed single crystal patterns of the α crystal form projected along the b -axis and the a -axis, respectively. By photo-irradiation the color of the film changed from yellow to white. The photo-irradiated film was identified by means of infrared spectroscopy as poly-DSP containing cyclobutane rings. The electron diffraction pattern obtained from the polymer film showed a similar net pattern as that of the monomer crystal, although the lattice spacings shrinked slightly in the direction of the a - and c -axes and elongated in the direction of the b -axis. The polymer film was of extremely high crystallinity and the 200 and 020 lattice fringes with spacings of 0.91 and 0.54 nm, respectively, were observed in the polymer film. The photopolymerization mechanism is discussed and it is concluded that the photopolymerization of DSP films occurs within the monomer matrix through a homogenous reaction and that it proceeds through a direct rearrangement of molecules from the monomer to the polymer crystal.

2,5-Distyrylpyrazine (DSP) was evaporated onto a cleavage face of KCl crystal in vacuo. The DSP film vacuum-evaporated on the KCl substrate without heat treatment was composed of randomly-oriented laminate and needle-like crystallites of α-form. When the substrate was heated at 150°C before vacuum evaporation and kept at 30°C during deposition, the DSP film was composed of slender needle-like crystallites of γ-form and flaky crystallites of α-form. The longitudinal direction of the γ-form crystals was aligned along the [100] and [010] directions of the KCl substrate. The faces of the α-form crystals made an angle of 10° with respect to the [100] and [010] directions of the KCl substrate. At the substrate temperature of 70°C, the DSP film grew epitaxially on the substrate to form thin plate-shaped crystals of γ-form. The DSP molecule took three kinds of orientations on the KCl substrate depending on the evaporation conditions: (100) α-form ∥(001) KCl , (010) α-form ∥ (001) KCl and [100] γ-form ⊥(001) KC l . These orientations are discussed in terms of the dehydroxylation of the KCl surface caused by the thermal treatment and of the adsorption energy of the DSP molecules.

The electrochromism of an octacyanophthalocyanine (H2Pc(CN)8) thin film was investigated by in situ visible and Raman spectroscopies in acid and alkaline electrolytes. A new absorption band was observed in the range 700–900 nm of the visible spectra during a reduction of the film. The absorbance reached a constant value at 2 F mol−1 of the cathodic electricity in an alkaline electrolyte. The Raman spectra showed a spectral change in the vibration range which is attributed to the macrocycle and the isoindole moiety; hence, the reduction seems to occur in the azaporphyrin ring. From both the visible and Raman spectra, it was revealed that H2Pc(CN)8 was protonated at the nitrogens in positions 6,13,20,27 by electrochemical reduction. The protonated H2Pc(CN)8 shows absorption in the near-infrared region in both acid and alkaline electrolytes. The mechanism for the formation of protonated H2Pc(CN)8 is considered to be analogous to that of hydrogen evolution in alkaline electrolytes. Both the visible and Raman ...

Mainchain photo-scission in a polymer chain often occurs via oxidation. The rate-determinig step of the chain scission is abstraction of a hydrogen atom accompanied by hydroperoxide formation. Solvent and temperature effects in the photochemical chain scission were studied to promote the photodegradation for prevention of plastic waste pollution. Rate of the mainchain scission was dependent on the species of the organo-halogen solvents of the polymer solution for irradiation, but did not increase linearly with rising temperatures.

Dark- and photo-electrochemical properties of an orientation-controlled thin film of 5,10,15,20-tetraphenylporphyrin (TPP) were investigated in the indium–tin oxide(ITO)/TPP/I3−,I−/Pt system. The oriented film exhibited a photocurrent quantum yield three times as great as the polycrystalline film. This enhancement in quantum yield may be attributable to the standing molecular orientation of TPP on the ITO substrate.

The crystal growth and the orientation of thin films of 5,10,15,20-tetraphenylporphyrin (H 2 TPP) vacuum-evaporated onto substrates of a KCl (001) surface and a semitransparent A1 electrode film have been investigated by electron microscopy and electron diffraction. The films deposited on a KCI (001) surface show epitaxial growth in which the crystals take a four-directional orientation, and the molecular plane of HzTPP stands perpendicular to the substrate surface. The H 2 TPP crystals with a morphology of rectangular islands grow on the KCI surface kept at 200 ° C, while a continuous thin film totally covers the KCI surface kept at 20 ° C with an identical epitaxial orientation. When H 2 TPP is deposited on a KCI (001) surface coated partially with a small number of Al particles, the crystals take the same orientation. This epitaxial orientation decreases with increasing the coverage of the A1 particles on the KCI surface, and the H 2 TPP film deposited on a semitransparent A1 film shows a random orientation of needle-like crystals. The growth of the thin film with oriented crystals depends on the electrostatic interaction of the H 2 TPP molecules with ionic charges on the KCI surface.

Octacyanometalphtha1ocyanine-metal [MPc(CN)8-M] complex crystals are synthesized by vapor-solid reaction of tetracyanobenzene with metal films and alkali halide crystals. Their crystal structures and orientations are directly analyzed by high resolution electron microscopy and electron diffraction. The MPc(CN)8-M complex crystals are composed of planar MPc(CN)o molecules packing parallel each other and intercalated metals. The M2Pc(CN)8-M (M:Na, K, Rb, Cs) complex crystals have the same interplanar distance of 0. 34 nm and their intercolumn distances increase in the order of Na- Fe-> Co-> Ni-> Cu-complex. Thin films of K2Pc(CN)8-K complex are composed of many crystallites with double directional orientation intersecting each other by an angle of about 23°. The crystals take three types of mutual orientations on a KCl (001) surface and the relative orientation of the deposited crystal to the KCl substrate is interpreted in terms of multiple positioning of the K2Pc(CN)8 molecules on an ionic lattice of the KCl surface.

2,5-Distyrylpyrazine (DSP) was vaccum-evaporated onto a cleavage surface of potassium chloride. The DSP film was composed of needle-like and laminate crystallines. The electron diffraction pattern from the film showed single crystal patterns projected along either the b-axis or the a-axis. The color of the film changed from yellow to white by photoirradiation. The photoirradiated film was identified as polyDSP containing cyclobutane rings by means of infrared spectroscopy. The electron diffraction pattern from the polymer film showed the similar net pattern as those of the monomer crystal, although the lattice spacings shrank slightly in the directions of the a- and c-axes and elongated in the direction of the b-axis. The polymer film had extremely high crystallinity and the 200 and 020 lattice fringes with spacings of 0.91 nm and 0.54 nm, respectively, were observed in the polymer film. From the electron microscopic observation, it was evident that polymerization of monomer crystal proceeded through a direct rearrangement to the polymer crystal

The structural change of 2,3,9,10,16,17,23,24-octacyanophthalocyanine(H 2 Pc(CN) 8 ) in a thin film caused by intercalation of potassium and electroreduction was observed directly by means of high-resolution electron microscopy(HREM). The H 2 Pc(CN) 8 molecules in a microcrystal precipitated from the acetone solution packed in the herring-bone structure. The crystalline film of the intercalation compound(H 2 Pc(CN) 8 -K) synthesized from 1,2,4,5-tetracyanobenzene(TCNB) vapor on KCl had the complex structure, in which H 2 Pc(CN) 8 molecules stacked in parallel and the potassium atoms were intercalated between the layers of the H 2 Pc(CN) 8 molecules. The film showed a stable electrochromic reduction together with the color change from green to blue. By electroreduction the staggered molecules along the stacking column in the complex crystal were slipped in the layer to form an alternately slipped stacking of molecules in the blue phase. This change of the molecular stacking was attributed to the repulsion between the conjugated π-electron system of the electrochemically reduced phthalocyanine macrocycles.

The dynamic moduli, E′ and E″, and tan δ for nylon–CR and PET–CR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed two dispersion peaks for nylon–CR composite. The peak at −28°C corresponded to the main dispersion of CR and the peak at 100°C to the α-dispersion of nylon 6. For a PET-CR composite, in addition to the individual dispersion of CR and PET, a small and broad peak was observed at about 90°C. The angular dependence of E′ indicated that the short fibers assumed good orientation. The storage modulus for the composites was given by the parallel model as E′ = Vf′Ef + VmE′m., where E′c, E′f and E′m were the storage modulus for the composite, fiber, and matrix and Vf and Vm were the volume fraction of fiber and matrix, respectively. In the transverse direction of fiber, the peak values of tan δ at −28°C were given by the following equation; tan δc = tan δm − δVf, where tan δc and tan δm are the loss tangent for the composite and matrix, respectively, and α is coefficient depending on fiber type. The results indicated that a region with strong interaction was formed between fibers and CR matrix.

Thin films were prepared by the reaction of 1,2,4,5-tetracyanobenzene with Ni, Co, Fe, Zn films at various temperatures. The films were characterized by infrared, UV/visible and photoelectron spectroscopy and analytical electron microscopy in comparison with films prepared on substrates of a KCl single crystal and a Cu film. The films produced on the metal films below 400 °C were composed of tentacle-like crystals growing from the surface and an amorphous layer condensed over the metal substrate. The tentacle-like crystals were soluble in concentrated sulfuric acid and were identified as intercalation compounds of (octacyanophthalocyaninato)metal with the respective metal atoms. The amorphous layers contained polymerization products with a polynitrile structure, which were insoluble in concentrated sulfuric acid. The films produced on the metal films at 450 °C were composed of a thick layer and had a very limited solubility in concentrated sulfuric acid. They were ascribed to metal complexes of polyphthal...

空気接触下, 1, 2-ジクロロエタン及びシクロヘキサン溶媒中でポリスチレンUV照射を行い, 主鎖切断の進行とともに変わる蛍光スペクトル挙動を測定した. シクロヘキサン溶液でUV照射したポリスチレンのピーク波長は未照射ポリスチレンのスベクトルの波長と同じであるが, 1, 2-ジクロロエタン溶液中で照射したポリスチレンの蛍光波長は長波長側にシフトした. 主鎖切断速度とカルボニル基生成速度も1, 2-ジクロロエタン溶液中の方がシクロヘキサン溶液中よりも大きかうた. シクロヘキサン中での照射時間とエキシマー形成量との関係は照射2時間までは減少, 以後8時間までは増加, それ以後は減少する挙動を示した. 劣化の進行とともに, 主鎖に結合している水素がカルポニル基や塩素原子により置換され, エキシマー形成が阻害さ れるので, エキシマー発光が減少したと考えられる.

The fatigue behavior of short fiber-rubber composites was studied by stress relaxation. The stress relaxation test of composites was carried out in the direction of fiber orientation under 5, 10, 15 MPa of initial stress and 4, 80, 400%/min of initial strain rate. The faster the initial strain rate, the higher the modulus of composites in stress-strain curves. This phenomenon seems to be caused by delay of flow of the interfacial region between fiber and rubber under deformation process. On the other hand, the faster the strain rate, the larger the stress decay at initial stage. It suggests that the interfacial region contains the large distortion under the fast strain.The stress relaxation tests and the observation of rupture surface for rubber matrix and composite after swelling by toluene were undertaken in order to understand the properties of the interfacial region. It seems that the composites include the weak bond between fiber and rubber matrix, because the stress relaxation of composites after swelling is smaller than that of composites before swelling. From the results of the observation of the fracture surface, it seems that the fracture of composites are caused by propagation of nuclei, which is initiated by the destruction of interfacial region, to the other interfacial region.

The dielectric constant and the dielectric loss of a monohydroxy molecule (glycerol diacetate) and a dihydroxy molecule (glycerol monoacetate) in the pure liquid state were measured over the frequency range from 23 Hz to 3 MHz in order to elucidate the relation between the steric effects of the acetoxyl group and the dielectric properties of alcohols. For a better understanding, the results of this work were discussed together with those of glycerol and glycerol triacetate. The static dielectric constants decrease in the order of glycerol, glycerol monoacetate, glycerol diacetate, and glycerol triacetate. This order agrees with the order of the decreasing number of hydroxyl groups per molecule. On the other hand, the four curves of a temperature variation of the relaxation times almost form one curve, although the molecular weights and interaction, which are important factors for the determination of relaxation times, differ greatly among the four molecules. Accordingly, it is concluded that the decrease ...

The dielectric properties of 2,4,6-heptanetriol triacetate, a model substance for poly(vinyl acetate), were studied to clarify significant roles played by the molecular structure in the α-relaxation behavior of polymers. At room temperature, this trimer of vinyl acetate is a viscous mixture of three stereoisomers, i.e., syndio-, iso-, and hetero-tactic 2,4,6-heptanetriol triacetate. Dielectric measurements for each isomer and for the mixture were carried out in a frequency range from 23 Hz to 3 MHz in a pure liquid state. The dipole moments in a carbon tetrachloride solution were also measured. The static dielectric constant was largest for the syndiotactic compound and smallest for the isotactic compound. In the above frequency range, the syndiotatic and isotatic isomers showed dielectric dispersions due to rotation of the molecule as a whole and the relaxation parameters were calculated by means of the asymmetric Havriliak–Negami empirical equation. It was found that the distribution of relaxation times for the isomers is almost the same as that for poly(vinyl acetate). It was concluded that the width and asymmetry of the distribution, at least in the case of the vinyl acetate trimer, can not be attributed to the fact that this trimer is a mixture of the three stereoisomers.

ベンゼン, シクロヘキサン, エチルベンゼン, エチルシクロヘキサン, 及びデカリン中に溶解させたポリスチレンに20℃から沸点までの広い温度範囲で紫外光を8時間照射した. 照射ポリスチレンの分子量, 生成カルボニル基量, ゲル量を定量した. 主鎖切断数はすべての溶媒中で照射温度100℃までは温度上昇とともに増加した. 他方, エチルシクロヘキサンとデカリン中では100℃以上の高温になると温度上昇とともに減少した. 照射ポリスチレン中に生成したカルボニル基生成量の照射温度依存性は切断数の照射温度依存性に対応し, 酸化を経由する光分解反応であることがわかった. 100℃における主鎖切断速度が極大となる理由はわからなかった.

The change in stress and surface temperature of short fiber-rubber composites under a repeated constant displacement were measured. The fatigue test was carried out in the direction of fiber orientation of composite with 5% of static strain and ±2.5% of sinusoidal strain under 5 and 25Hz. By giving intermission repose at the mid of the fatigue test, the effect of duration of intermission and fatigue cycles until intermission on change in the stress and surface temperature was investigated.Under the condition of high sinusoidal strain rate, the interfacial region between fibers and rubber matrix giving rapid displacement is destroyed and the internal heat generation is large. Consequently, the stress decreases radically and the surface temperature rises till the slip of the short fibers takes place by the destruction of the interfacial region. It seems that the stress decay of composite was caused by the destruction of interfacial region and the internal heat generation from the results of measuring stress and surface temperature before and after duration of intermission under discontinuous fatigue test. The composite shows the recovery of the strain including the interfacial region between fibers and rubber matrix when the duration of intermission is applied before the slippage of the short fibers.

ナイロン及びPETの短繊維をCRもしくはEPDMに充てんした複合体中の短繊維とゴムマトリックスの界面における配合剤の濃度分布をEMXを用いて求めた. RFLにて接着処理した短繊維-CR複合体の場合, 短繊維とCRの界面から数μmのマトリックス中に亜鉛とマグネシウムの凝集が観察された. PET-EPDM複合体では界面に亜鉛の凝集は観察されず, 加硫剤である硫黄が凝集した. ゴムとRFLの薄膜の積層体では, 短繊維-ゴム複合体と同様にCRでは亜鉛とマグネシウム, EPDMでは硫黄の凝集が界面近傍に認められた. CRに加えられた金属酸化物は混練, 加硫工程中に脱塩酸反応及び加硫反応により塩化物となり, 短繊維表面のRFL中の水分に引き寄せられ凝集したものと思われ, PET-CR複合体の場合, 試料を吸•脱水することでこれら塩化物の凝集は消失したが, 親水性のナイロンとCRの複合体ではナイロンは水分を強く引きつけるため, 水に溶けている金属塩化物の凝集はほとんど変化しなかった. PET-EPDM複合体では, 未反応の遊離硫黄が異相との界面に移行し凝集したものと思われる. 更に, これらの配合剤は圧着加硫中にゴムからRFL内に移行する現象が認められたことから, ゴムと同時にRFL膜も架橋し, 短繊維とゴムの接着を一層強固にしていると思われる.

The dielectric properties of 2- and 4-methylcyclohexanols were studied in order to elucidate the molecular geometric dependences of the dielectric properties of alcohols. The Kirkwood correlaton factors g of the trans isomers are larger than those of the cis isomers. Especially the g of cis-2-methylcyclohexanol at 298 K is 0.75. The dielectric relaxation of all the methylcyclohexanols studied shows the characteristics of the Debye-like behavior frequently reported for primary alcohols. The activation energy of dielectric relaxation of 2-methylcyclohexanol is much larger than that of the other methylcyclohexanols. These facts are discussed in terms of the difference of the steric hindrance for the association through the hydrogen bond.

Octacyanometalphthalocyanine-metal complex (MPc(CN) 8 −M, M = Cu, Ni, Co, Fe, Zn and K 2 Pc(CN) 8 − K ) crystals were synthesized by vapor-solid reaction of tetracyanobenzene (TCNB) with metal films and a KCl crystal. Their crystal growth was investigated by electron microscopy. The crystal morphology depended on reaction temperature, pressure and kinds of substrate. Crystals of MPc(CN) 8 −M and K 2 Pc(CN) 8 −K grew long and thick, tentacle-like, on polycrystal metal films and on a KCl (001) surface at the reaction temperature of 350°C. Growth of the crystals was inactive at reaction temperatures below 300°C. Crystal defects such as bends and folds increased with rising reaction pressure. The growth mechanism was assumed as follows: MPc(CN) 8 molecules are formed on a substrate metal by tetramerization of TCNB vapor, and peripheral nitrile groups of MPc(CN) 8 molecules coordinate to metal atoms of the substrate to form a MPc(CN) 8 − M complex. MPc(CN) 8 molecules are piled up in parallel to form a column structure and the complex crystal grows by diffusion of metal atoms from the substrate. The crystal growth is well-defined when metal atoms are supplied sufficiently from the substrate.

The dynamic moduli, E′ and E″, and tan δ for PET–CR, PET–EPDM, and PET–UR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed three peaks for PET–elastomer composites. The peaks at the low temperature corresponded to the main dispersion of the respective matrixes and the peak at about 140°C to the α-dispersion of PET fiber. A small and broad peak observed at a temperature between 60 and 120°C may be caused by the relaxation of the interface region between fibers and matrix. The longitudinal storage modulus for the composite E was given by the parallel model as , where E and E are the storage moduli for fiber and matrix and Vf and Vm are the volume fraction of fiber and matrix, respectively. In the transverse direction of fibers, the composite modulus E was expressed by the logarithmic law of mixing as follows: . The peak values of tan δ from the main dispersion of the respective matrixes were given by the equation, (tan δ⊥max)c/(tan δmax)m 1 − β · Vf, where (tan δ⊥max)c and (tan δmax)m are the maximum values of the loss tangent for the composite and matrix, respectively, and β is coefficient depending on matrix's type. The β value of PET–CR composite is the largest one among those of the composites.

The epitaxial crystallization of hexatriacontane vacuum-evaporated onto a gold-covered KCl (001) surface was investigated as a function of the gold coverage. The hexatriacontane film on the KCl surface was composed of rod-like crystals taking the orientation of (110)H//(001)KCl and [001]H//[110]KCl. The film on evaporated gold film was composed of lamellar crystals taking the orientation of (001)H parallel to the substrate and a random orientation in the azimuthal direction. The hexatriacontane film evaporated on the substrate which was partly covered with gold particles was composed of both rod-like and lamellar crystals. When the coverage ratio of the gold particles was low, the lamellar crystals in the hexatriacontane film took the orientation of (001)H//(001)KCl and [110]H//[110]KCl. The numbers of lamellar crystals increased, and their orientation in the azimuth became more random, with and increase in the gold coverage.

The change in strain of short fiber-rubber composites under repeated constant load was investi-gated. The short fibers in the composites were oriented to the uniaxial direction. The fatigue test of composites was carried out in the direction of fiber orientation under 25 Hz of frequency and 6±2, 8±4 and 10±2 MPa of sinusoidal load. The change in strain of composites under-fatigue test was characterized with two stages, i.e. the strain linearly increased with increasing cycles at the initial stage, and then the strain showed marked increase deviating from an extrapolated straight line at the higher cycles. It seems that the former was caused by the deformation of interfacial region between fiber and rubber, and the latter was taken place by the destruction of interfacial region. This change in strain was restrained by the RFL-treatment and high loading of short fibers. It was also found that under the dynamic fatigue of large displacement, the destruction of interfacial region occurred at the early stage, since the interfacial region was difficult to deform with the displacement of sinusoidal stress.

Thin oriented films of some organic compounds can be prepared by either the vacuum-deposition method or the Langmuir-Blodgett method. The characterization of the structure of thin films is carried out by electron microscopy. The orientation of thin films is determined by several experimental methods : electron diffraction, decoration and high resolution electron microscopy for the vacuum-deposited films, and shadowing and replica methods for L-B films.