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Copyright of Journal of the Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku is the property of Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku is the property of Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku is the property of Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Kobunshi Ronbunshu is the property of Society of Polymer Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Kobunshi Ronbunshu is the property of Society of Polymer Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Kobunshi Ronbunshu is the property of Society of Polymer Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Kobunshi Ronbunshu is the property of Society of Polymer Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper described the effect of friction welding condition on joining phenomena and tensile strength of ABS resin friction welded joint. When the joint was made with a friction speed of 4.2 s-1 and a friction pressure of 0.3 MPa, the temperature at the weld interface at a friction time of about 45 s or longer exceeded 130 ℃. That is, the temperature at the weld interface of the ABS resin friction welding exceeded the glass transition temperature of its resin. When the joint was made with a friction time of 60.0 s, it obtained approximately 67% joint efficiency. However, the joint efficiency decreased with increasing friction speed, and it also decreased with decreasing friction speed. The joint efficiencies with other friction pressures showed a similar change although the friction speed differed. When the joint was made with a friction speed of 2.5 s-1, a friction pressure of 0.3 MPa and a friction time of 180.0 s, it obtained over approximately 90% joint efficiency. However, the joint efficiency decreased with increasing friction time, and it also decreased with decreasing friction time. Furthermore, the joint efficiency increased with decreasing parallel part diameter of the joint tensile test specimen, and that achieved 95% joint efficiency. In conclusion, to obtain the higher joint efficiency, the joint should be made with opportune friction speed, friction pressure and friction time, and the friction welding should be completed when the whole weld interface became melting state.

We investigated radical copolymerization of styrene dimers [2,4-diphenyl-l-butene (STD)] and trimer [2,4,6-triphenyl-1-hexene (STT)], that are thermal degradation products of polystyrene, with maleic anhydride (MAn) at 60°C in THF or in bulk as a method for polymer recycling. The copolymerization of STD and MAn gave high-molecular-weight alternating copolymers [poly(STD-co-MAn)] (Mn = 10,000~30,000) in moderate yields (50~70%), while the copolymerization of STT and MAn gave alternating copolymers [poly(STT-co-MAn)] with a lower molecular weight (Mn = 6,000~17,000) and in lower yields (10~20%). The glass transition temperatures (Tg) of poly(STD-co-MAn) and poly(STD-co-MAn) were 211°C and 116°C, respectively. The hydrolysis of poly(STD-co-MAn) in water followed by sodium hydroxide addition gave water-soluble poly(STD-co-MAn) with pendant carboxylate groups [poly(STD-co-MAn)-COONa]. [ABSTRACT FROM AUTHOR]

Ethylene-norbornene random copolymers (ENRC) have been attracting much attention as optical materials in recent years, because they have excellent properties such as low water absorption, high glass transition temperature and high light transmittance. We therefore investigated the photo-degradation of an ENRC using laboratory-made irradiation apparatus using a wavelength of 405 nm. It became clear that even after an irradiation time of up to 1000 hours no chloroform insoluble material was formed. Instead, we observed mainchain scission and the formation of photodegradation products such as aldehydes and formates. We found that these photodegradation products are similar to those of samples that were irradiated using a xenon weathermeter (λ > 290 nm) but that the amount of photodegradation products differs. [ABSTRACT FROM AUTHOR]

Hierarchical microstructures in beetle epidermis layers enable a wide variety of structural colors. However, conventional artificial mimicking techniques are limited, mainly, to multi-layer film formation or 3D colloidal crystal array assemblies on flat substrates. In this paper, we propose a new method applying hot embossing using a metal mesh pressed onto the self-assembled opal film on a plastic substrate. Firstly, opal films composed of 0.2 µm polystyrene colloids and infilling elastic silicone polymer were coated on flat polyvinyl chloride (PVC) sheets. Then the surface of the opal film was thermally deformed by pressing a micro structured mold into it above the glass transition temperature. Micro-spectroscopic analysis revealed that the spectral reflection from the tip of a convex shaped dome was the same as the one from the flat area under a tilting angle of 25 degrees. Our new method is expected to contribute to the fabrication of future complex biomimetic structural color elements. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) have been proposed as solid-state alternatives to liquid electrolytes in electrochemical applications such as all- polymer Li batteries. However, these suffer from low ionic conductivity in the solid state compared with common liquid, gel and ceramic electrolytes. In this study, the preparation of SPEs using an alternative copolymer obtained from CO2 with an epoxide monomer instead of polyether was proposed synthesized and evaluated as a novel polymer candidate for SPEs. We used four types of polycarbonates (PCs) possessing different alkyl side groups; the SPE samples were prepared by the addition of 20-80 mol% LiTFSI. In all PC-based electrolytes, the glass transition temperature linearly decreased and the ionic conductivity increased with increasing LiTFSI concentration. Furthermore, longer alkyl side chains in PC decreased the conductivity, because the alkyl groups prevented LiTFSI dissociation. [ABSTRACT FROM AUTHOR]

We report a novel method for determination of glass transition temperatures that applies the phenomenon of microwave power saturation in electron spin resonance (ESR). Amorphous polystyrene (PS) and semi-crystalline polyethylene (PE) were used as samples for the measurement. In order to evaluate the glass transition temperature (Tg) at the specific sites in the polymers, we spin-labeled the end or inner segments in PS and inner segments in PE with paramagnetic species. When the microwave power is small enough, the intensity of ESR spectrum is proportional to the square root of the magnitude of the microwave power. However, the intensity of the spectrum no longer increases when an excess power is applied. This is the power saturation phenomenon which is influenced by the relaxation time of the molecular mobility around the spin labels. No significant difference in Tg of PS between end and inner segments was revealed by the ESR microwave power saturation method. This can be explained by in terms of cooperation in the segmental motion at the Tg. As for PE, it was found that Tg in the amorphous region of PE depended on the crystallinity. [ABSTRACT FROM AUTHOR]

Dielectric properties were investigated for quenched films of polyamides consisting of piperazine and aliphatic dicarboxylic acids with the number of carbon atoms from 7 to 10 over a frequency range from 25 Hz to 1 MHz, at temperatures from 200 to 450 K. The α and γ relaxations were observed in decreasing order of temperature. The α relaxation was observed at temperatures above the glass transition. Frequency dependence of dielectric constant and loss for the α relaxation was not symmetrical about the relaxation frequency and skewed toward high frequency. Values of dielectric strength of the relaxation were 10 to 13 for polyamides with an odd number of carbon atoms in the dicarboxylic acids and 3.9 to 4.0 for polyamides with an even number of carbon atoms in the dicarboxylic acids. The α relaxation was related to the reorientation of the N-C=O group by the micro-Brownian motion of molecular chains. The β relaxation observed for the wet Pip9 at temperatures below room temperature was due to molecular motions of the H2O attached the C = O group. The y relaxation observed for Pipn at lower temperatures than those for the β relaxation was related to the local molecular motions of methylene sequences. [ABSTRACT FROM AUTHOR]

The color change from pale yellow to vermilion due to the UV-irradiation and the reverse color change due to the heating at about the glass transition temperature (g) were investigated for the poly(lactic acid) (PLA) mixed with 9,10-anthraquinone (AQ) by electronic absorption and IR analysis. The absorption of the broad band around 485 nm assigned to the electron donor acceptor (EDA) between AQ and anthrahydroquinone (AQH2) was increased by UV-irradiation and was decreased by the heating at about the glass transition temperature. The color change and reversion was possible by repeating the UV irradiation and the heating operations. A decrease of AQ and a formation of AQH2, by the UV irradiation and a increase of AQ and a small decrease of AQH2 by the heating were observed from the IR measurements. The formation of the AQ-AQH2EDA complex which hydrogen bonded with PLA was a cause of coloration and the dissociation of EDA was a cause of fading. At the same time, some of AQH2 was oxidized to AQ. [ABSTRACT FROM AUTHOR]

Thermosetting epoxy resins containing polyaromatic backbones such as naphthalene and dihydroanthracene showed low coefficients of thermal expansion (CTE) and high glass transition temperatures. 4,4′-Diaminodiphenyl sulfone (DDS)-cured polyaromatic epoxy resin showed a CTE of 49.8 ppm/K with a Tg of 235°C. These values are 15.3 ppm/K lower and 19°C higher than those of DDS-cured bisphenol A type epoxy resin (DGEBA), and 22.0 ppm/K lower and 77°C higher than those of cresol novolac(CN)-cured DGEBA. There is a correlation between density and CTE of the cured resins, some contribution of the π-π stacking effect for polyaromatic backbones of epoxy resins and the stereostructure of DDS to decrease in CTE was indicated. Moreover, boron trifluoride monoethylamine complex (BTMEA) was found to be effective as a curing accelerator for DDS-cured epoxy resins. [ABSTRACT FROM AUTHOR]

Polystyrene ultra-thin films with a thickness below the diameter of gyration (~55 nm) were prepared by spincasting of toluene precursor solution; the dependences of their physical properties (density ρ, glass transition temperature Tg, and relaxation time τ) on concentration were examined by means of ellipsometry and X-ray reflectometry. For 22 nm-thickness film, Tg was reduced with decreasing polymer concentration of the precursor below the overlap concentration of polystyrene, whereas ρ at room temperature was increased, in comparison with the bulk state. Evaluating of τ for the un-relaxed film dried at room temperature clearly showed that τ was shortened with decreasing precursor concentration, indicative of an increase of the molecular weight of an entanglement strand. This signifies that the involved local motion of the polymer chain contributes to the reduction of Tg. An important role in the reduction of Tg, specific to ultra-thin films, was found to be played by the interaction between polymer chains in the precursor solution at spincasting. [ABSTRACT FROM AUTHOR]

The moisture-absorbed polyketone (PK)/polyamide (PA) polymer alloys show higher impact properties than polycarbonates (PC). TEM observations and SAXS measurements revealed that the co-continuous structure is formed from the PK rich phase and the PA rich phase of the polymer alloy. On the other hand, by solid state NMR spin diffusion method, the domain size of PK and PA was estimated to be form several tens nm to a few hundred nm (T1), whereas the domain size of both PK and PA is larger than a few nm (T1p). In addition, the shift of the glass transition temperature of the PK and PA components indicates the existence of some interactions between PK and PA in the alloy; Additionally; the NMR relaxation time measurements suggest that the molecular motiori of PA was enhanced remarkfibly by the selective moisture adsorption on the amorphous phase of PA for alloys. We concluded that the impact properties of PK/PA alloys are improved with increase of elasticity for amorphous regions of PA by moisture absorption. [ABSTRACT FROM AUTHOR]

Stress fluctuating phenomena (Unstable necking deformations) are especially observed in the cold drawing of polyethylene telephtha-late monofilaments. In the temperature range below glass transition temperature, maximum drawing stress and fluctuating range of the stress are strongly dependent only on the drawing temperature and these values decrease linearly with the rise in the drawing temperature. This phenomenon can be explained by the relationship between the local temperature rise due to the necking deformation and the critical necking stress of semicrystalline polymer. Furthermore, the deformation behavior of undrawn monofilament with stress fluctuation phenomenon drawn below the glass transition temperature can be theoretically simulated by assuming that the mechanical property of undrawn part of monofilament is represented by a standard linear solid model obtained by adding a second spring element in parallel with the Maxwell unit. [ABSTRACT FROM AUTHOR]

Physical aging of optical polymer glasses was studied by refractive index measurements. We measured the change of refractive index of polystyrene (PS) glass after annealing at temperatures below its glass transition temperature (Tg) by optical prism coupling, and determined volume relaxation by physical aging using the Lorentz-Lorenz equation. The maximum volume relaxation for PS glass occurred at 20°C below Tg. [ABSTRACT FROM AUTHOR]

Light scattering of amorphous optical polymer glasses was studied to investigate the local structure. The light scattering loss of poly (methyl methacrylate) (PMMA) glasses varied widely with polymerization conditions, even though a contaminant-free monomer were used. PMMA glasses polymerized below the glass transition temperature (Tg) had an excess scattering loss due to a large-size (tens of nm) heterogeneous structure with a refractive-index difference of the order of 10-4. With polymerization above Tg, no excess scattering was observed. On the other hand, polystyrene (PS) glasses polymerized below or above Tg had no excess scattering, and thus no large size heterogeneities. The origin of the large heterogeneous structure in amorphous polymer glass is discussed. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) such as poly (ethylene oxide)-metal salt complexes have been proposed as solid-state alternatives to liquid electrolytes in electrochemical device applications such as all-polymer lithium batteries. However, SPEs suffer from relatively low ionic conductivity in the solid state compared with most liquid, gel and ceramic electrolytes. For increase in the migration of ions, we have been focusing on compressed carbon dioxide, especially supercritical carbon dioxide (scCO2) as a unique solvent for SPEs. The treatment of SPEs with scCO2 gave rise to a large increase in the conductivity of polyether-Li salt complexes. Moreover, we measured the conductivity directly in pressurized CO2. The SPEs revealed a significant increase in the conductivity in the high-pressure conditions. It was found that CO2 plays an important role for adsorption, plasticization for polymers and dissociation of aggregated ions. CO2 is able to cause a dramatic decrease in the Tg of SPEs leading to an increase in the conductivity in solid state. [ABSTRACT FROM AUTHOR]

Carboxymethylcellulose (CMC)-based polyurethane (PU) hydrogels were prepared from the solutions of CMC and hexamethylene diisocyanate (HDI). Water content [Wc = (mass of water) / (mass of dry sample)] of the obtained PU hydrogels was less than 3.0 g g-1 and NCO/OH ratio was varied from 0.2 to 0.6 mol mol-1. Phase transition behaviour of CMC-water systems and CMC-PU hydrogels was investigated in the temperature range from - 150 to 80°C by differential scanning calorimetry (DSC). From DSC heating curves, glass transition temperature (Tg), melting peak at low temperature side (Tml), and melting peak at high temperature side (Tmh) were observed. The Tg minimum value increased with increasing NCO/OH ratio indicating that the molecular motion is restricted by cross-linking. From the enthalpy of melting, it was confirmed that there exist three kinds of water, non-freezing water, freezing bound water and freezing water respectively. [ABSTRACT FROM AUTHOR]

Novel linear polyurethanes were Synthesized by the reaction of methyl (S)-2,6-diisocyanatohexanoate (LDI) with bis (2-hydroxyethyl) terephthalate (RHET) and poly (ethylene glycol) (PEG). The polymers were obtained in relatively high yields (95∼98%). Their number-average molecular weights determined by GPC were in the range from 2.1 × 104 to 2.4 × 104 and the polymers showed a glass-transition temperature at about - 13°C by dynamic mechanical analysis. The polymers were rubber-like, elastic materials with high tensile strength of ca. 83 MPa. Enzymatic degradation of the polymers esulted in a weight loss of up to 98%. Moreover, numerous holes and hollow structures were observed on the surface of the degraded films by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry (DSC), dielectric relaxation measurement, friction measurement, and infrared spectroscopy were used to characterize addition-cured silicone pressure-sensitive adhesive (ASPSA). A stepwise decrease was observed at 30°C for the heat capacity of crosslinked ASPSA in contact with metal or metal oxide, while there was no step decrease for non-crosslinked ASPSA in contact with metal or metal oxide. The mechanism of adhesion of ASPSA is discussed based on the interaction between silicone resin in ASPSA and metal interfaces. [ABSTRACT FROM AUTHOR]

Hydroxy-terminated telechelic polyacetals (PHBVE) were synthesized by polyaddition of 4-hydroxybutyl vinyl ether (HBVE; CH2 = CH-O-CH2CH2CH2CH2-OH) in the presence of 1,4-butanediol (BD) with an acid catalyst in tetrahydrofuran (THF) at 0°C. Polyurethane elastomers with polyacetal soft segments (PHBVE-PU) were synthesized by the reaction of PHBVE with an excess amount of 4,4'-diphenylmethane diisocyanate and the subsequent chain-extension reaction with BD. PHBVE-PUs exhibited low glass transition temperature, high thermal stability, and good elastomeric properties. The effects of the Mn of polyacetal prepolymer on the thermal and mechanical properties of PHBVE-PUs were investigated. PHBVE-PU underwent smooth degradation with the treatment of aqueous HCl in THF at room temperature to give BD and urethane hard-segment residues as degradation products. [ABSTRACT FROM AUTHOR]

New structure-controlled A2 + B3 type hyperbranched (HB) polymers containing a phenylstilbene analogue (PEPT) of 1,3,4-thiadiazole as mesogen in the interiors were prepared by solution polycondensation from dioxydiundecanol derivative of PEPT (A2) and trimesic acid trimethyl ester (B3) at various feed molar ratios (A2/B3) and their liquid crystalline (LC) and optical properties were examined. The structure of polymers changed depending on the feed molar ratios. Their number-average molecular weights increased after acetylation of terminal OH groups of the polymers. The HB polymer prepared with a feed molar ratio of A2/B3 = 3/2 had the maximum molecular weight. All HR polymers are soluble in organic solvents and formed enantiotropic smectic LC phases above their glass transition temperatures. The UV-vis and photoluminescent (PL) spectra of polymers displayed absorption and emission maxima in the blue region, but the fluorescence intensities were extremely weak. The properties of HB polymers were also compared with those of the corresponding linear polymers. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO) electrolytes doped with lithium salts have been studied by the multi-nuclear NMR methods for the glymes of the small molecular weights and the cross-linked solid polymers. The segmental motions of the PEO chain and the lithium hopping motions were analyzed from the spin-lattice relaxation times T1 of the ¹H and 7Li NMR. The diffusion phenomena were measured by the pulsed-gradient spin-echo (PGSE) NMR method for the individual components by ¹H, 7Li and 19F NMR (anions). When the solvents are liquids, all the components diffuse almost freely in the large temperature range; When the molecular weights of the solvents (polymers) become larger, the diffusion of the components become anomalous or restricted. The rate of the segmental motion relates with the glass transition temperature. The anion diffusion contributes mostly to the ionic conductivity. [ABSTRACT FROM AUTHOR]

New biodegradable polyurethanes were obtained from polycaprolatone diols (PCC2000 or PCL2000), methyl (S)-2,6-diisocyanatohexanoate (LDI), and 1,4-benzenediol or 1,4-butanediol. The inherent viscosities of the polymers were in the range of 0.41∼0.45 dL/g. These polymers were partially crystalline and showed glass transition temperatures (Tg) in the range of -5 to 60°C. They were thermally stable up to 255 to 281°C. These polymers formed flexible films with good stress-strain properties. The degradation behavior of the polyurethane put in the compost was evaluated by SEM and weight loss. The polyurethane degraded for 7 days showed a considerable number of voids on the surface. [ABSTRACT FROM AUTHOR]

The photochromism of the poly (methyl methacrylate) (PMMA) mixed with 9,10-anthraquinone (AQ) was investigated by spectroscopic analyses and molecular orbital analyses. The color of the material when irradiated with UV light has been confirmed to change from pale yellow to vermilion; the color reversion has observed after the heating up to about 373 K. The absorption at 380 nm increased after the irradiation and a broad band appeared around 485 nm. The former is assigned to anthrahydroquinone (AQH2) and the latter to the electron donor-acceptor (EDA) between AQ and AQH2. The coloration originates by the formation of the EDA complexes and the color reversion is their decay. We found that the hydrogen bonds are formed between a hydrogen atom of the OH group of AQH2 and an oxygen atom of the ester C = O group of PMMA during the coloration process. Hydrogen bonds might contribute to the stability of the EDA interaction between AQ and AQH2. [ABSTRACT FROM AUTHOR]

Hard and transparent zirconia films were successfully formed on a polycarbonate (PC) surface under mild preparation conditions (low temperature and ambient-pressure). Our process is based on the lamination of porous anodized zirconia membranes (PAZM) to the PC surface, followed by mechanical peeling with tweezers. By heating PC above its glass transition temperature, molten PC was successfully pulled into the nanopores through capillary force, followed by cooling to readily anchor the PAZM securely to the PC surface. Consequently, our resulting PAZM-laminated PC surface exhibited excellent adhesion and surface mechanical properties, while preserving the optical and bulk properties of the polymer. [ABSTRACT FROM AUTHOR]