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Size control of the poly (1,4-phenylene-5-hydroxyisophthalamide) hollow spheres was examined by tuning the polymerization condition, focusing on concentration, temperature and solvent. Higher concentration lowered the diameter owing to the higher degree of super-saturation for nucleation. Temperature drop during the polymerization just before the nucleation was so effective to make the diameter smaller. Moreover, the diameter was susceptive to the solubility of oligomers in the solvent, and higher content of liquid paraffin in the aromatic solvent lowered the solubility, resulting in the decrease in the diameter. Based on these results, the combination of the temperature drop and the solvent effect was the most desirable to prepare the smallest hollow spheres, and the diameter of hollow spheres could be controlled from 4.4 to 0.7 μm.

To clarify the effect of triazole (TR) group at the closing point within the cyclic polymer chain on the crystal growth, we studied morphology and the growth rate of spherulite G of cyclic poly(e-caprolactone) with a TR group at the closing point (C-TR-PCL) as a function of the degree of supercooling ΔT using polarizing optical microscopy. We prepared C-TR-PCLs synthesized by the ring-closing reaction from their linear precursors with Mw = 30000 and 50000, and cyclic PCL polymerized by ring expansion reaction (C-PCL) having no TR group with Mw = 26000, and linear PCL with/without a TR group at a chain end (L-TR-PCL-OH and L-PCL) with Mw = 26000 and 36000, where Mw was determined by GPC using linear polystyrene standards. We found that C-TR-PCL and L-TR-PCL-OH show banded spherulites at small ΔT and band-less normal spherulites with maltese cross at large ΔT. Whereas, C-PCL and L-PCL only showed band-less normal spherulites at any ΔT. This speculates that steric hindrance of TR group near the surface of crystals will become significant at small ΔT. G obeyed the equation, G = G0exp(−B/TΔT), for all the samples. B of C-PCL and L-PCL is constant irrespective of TΔT, however, that of C-TR-PCL and L-TR-PCL-OH showed two values depending on TΔT. At the region of lower B, i.e., small ΔT, the banded spherulites could be observed. The change of B corresponds to the morphological change of the spherulites. Since the size of the crystalline region closely related to lamellar thickness becomes large at small ΔT, TR groups excluded from the crystals become to assemble near the surface of the crystals. This is the reason why B becomes low at small ΔT. In C-TR-PCL with higher Mw and L-TR-PCL-OH, the decrease of B with decreasing ΔT becomes small compared to that of C-TR-PCL with lower Mw due to relatively small effect of TR group.

To elucidate the molecular weight (Mw) dependence of the growth rate of spherulite (G) of cyclic polymers polymerized by the ring expansion reaction, we studied the G of cyclic poly(e-caprolactone) (C-PCL) growing from the melt as a function of the crystallization temperature (Tc) and degree of supercooling (ΔT) using polarizing optical microscopy. We prepared C-PCLs comprising an exclusively repeating unit, excluding other structural units with Mw = 17000, 33000, 41000, 74000 and 85000 and linear PCLs (L-PCL) with Mw = 16000, 35000 and 60000, where Mw was determined by GPC using linear polystyrene standards. G obeyed the equation, G = G0exp(−B/TΔT), for all the samples. The activation energies of secondary nucleation (B) of C-PCL were almost identical except for the C-PCL with the lowest Mw. Since B is proportional to the end surface free energy of the secondary nucleus, it implies that the regularity of the folding surface of C-PCL with high Mw is independent of Mw. Compared to C-PCL and L-PCL having almost the same Mw, G of L-PCL is higher than that of C-PCL at the same TΔT. This suggests that G of C-PCL and L-PCL is not solely controlled by the entanglement because the entanglement of C-PCL is lower than that of L-PCL. We found the following associations: G0∝Mw−1.2 for C-PCL and G0∝Mw−0.67 for L-PCL. The difference in the power of the G0 dependence on Mw reflects the difficulty of performing sliding diffusion in the secondary nucleus. This strongly supports the hypothesis that the absorption behavior of C-PCL chains in the secondary nucleus on the growth front is significantly different from that of L-PCL.

金沢大学先端科学・社会共創推進機構, With the advent of high volume manufacturing capabilities by extreme ultraviolet lithography, constant improvements in light source design and cost-efficiency are required. Currently, light intensity and conversion efficiency (CE) measurments are obtained by charged couple devices, faraday cups etc, but also phoshpor imaging plates (IPs) (BaFBr:Eu). IPs are sensitive to light and high-energy species, which is ideal for studying extreme ultraviolet (EUV) light from laser produced plasmas (LPPs). In this work, we used IPs to observe a large angular distribution (10°-90°). We ablated a tin target by high-energy lasers (1064 nm Nd:YAG, 1010 and 1011 W/cm2) to generate the EUV light. The europium ions in the IP were trapped in a higher energy state from exposure to EUV light and high-energy species. The light intensity was angular dependent; therefore excitation of the IP depends on the angle, and so highly informative about the LPP. We obtained high-space resolution (345 μm, 0.2°) angular distribution and grazing spectrometer (5-20 nm grate) data simultaneously at different target to IP distances (103 mm and 200 mm). Two laser systems and IP types (BAS-TR and BAS-SR) were also compared. The cosine fitting values from the IP data were used to calculate the CE to be 1.6% (SD ± 0.2) at 13.5 nm 2% bandwidth. Finally, a practical assessment of IPs and a damage issue are disclosed. © 2017 Author(s)., Embargo Period 12 months

The extent of water sorption in a thin film of a typical glassy polymer, poly(methyl methacrylate) (PMMA), was studied by neutron reflectivity. Interestingly, the as-spun film could uptake water to 16.3 vol%, much more than the reported value of a few vol% for bulk PMMA. This can be explained in terms of the heterogeneous density distribution in the film.

At the outermost surface, aggregation states of polymers generally tend to alter to their most stable ones in response to their surrounding environment. We here apply a time-resolved contact angle measurement to study the rate of the surface reorganization of poly(methyl methacrylate) (PMMA) in water. By doing these measurements at various temperatures, it is possible to determine the apparent activation energy of the surface dynamics based on the relation of the surface relaxation time and temperature. Also, the sum-frequency generation spectroscopy revealed that the surface reorganization involves the conformational changes in the main chain part as well as the side chains. Hence, the dynamics observed here may reflect the segmental motion at the outermost region of the PMMA film, in which water plays as a plasticizer.

非溶媒中におけるポリメタクリル酸メチル(PMMA)薄膜の密度分布を中性子反射率測定に基づき評価した．非溶媒として水，ヘキサン，メタノールを用い，各種溶媒中における PMMA 薄膜の密度分布を評価した．その結果，水界面においては，PMMA 分子鎖がセグメントレベルで溶解することを明らかにした．また，水よりも PMMA と親和性の低いヘキサン界面においては，水を用いた際のようなセグメント溶解は起こらないこと，メタノール中では膜全体が膨潤することを明らかにした．非溶媒にアルコールを用いた場合，膜中における分子鎖は擬平衡状態にあるといえる．その状態における膜中へのアルコール収着の程度はアルコールのアルキル鎖長に依存した．また，膜内部におけるアルコールの体積分率から PMMA とアルコール間の相互作用(χ)パラメータを算出した．さらに，アルコールと接した PMMA 界面の広がりおよび基板界面における濃縮層の厚さはそれぞれ χ パラメータおよびアルコールのモル体積に依存することを見いだした．

Thin films of a typical glassy polymer in alcohol nonsolvents were structurally characterized by specular neutron reflectivity (NR) and were found to be discernibly swollen. The extent of penetration by the nonsolvent was determined by the chain length of the alcohol. Treating this situation as one of a macroscopic phase separation, the interaction χ parameters for the polymer and nonsolvents combinations were extracted. This observation leads us to investigate the factors that control the nonsolvent/polymer interface, being an unusual example of a liquid/liquid interface. The fractional amount of nonsolvents at the substrate interface was higher than that in the internal region of the film. This segregation of a component in a phase-separated domain was explained in terms of an entropic factor.

Qualitatively different thickness dependences have been observed in the glass transition temperature, Tg, of polystyrene (PS) films supported by hydrogen-passivated silicon (H−Si). It has been suggested that upon annealing at high temperatures in air, the polymer/substrate interface of these films (i.e., PS/Si), though buried underneath the PS layer, might be oxidized, rendering the films a different polymer/substrate interface (i.e., PS/SiOx−Si), which may account for the different thickness dependences of the Tg observed. In this experiment, we examine if the buried substrate interface of PS/H−Si films can indeed be oxidized by annealing the films at 150 °C in air. Our result shows that a residual film does form on top of the H−Si surface, but it is a bound layer of PS. X-ray photoelectron spectroscopic (XPS) analyses and independence of the residual film on the initial PS thickness evidence that the H−Si substrate buried underneath a PS film is not oxidized by annealing. We discuss a possible explanati...

Hyper-branched polystyrenes (HBPS) were synthesized. The bulk glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) for two kinds of HBPS with an equivalent Mw, which were fractionated from different lots, were different, being respectively higher and lower than that of the corresponding linear polystyrene (PS). Infrared spectroscopy revealed that the Tg of HBPS increased with an increasing extent of intramolecular cross-linking, or cyclization, in the molecule. The segmental dynamics of HBPS was examined by dynamic mechanical analysis. The relaxation temperature for the segmental motion in HBPS was consistent with the DSC results. The fragility index was always lower for HBPS than for the linear PS, regardless of its primary structure and chain end chemistry. This would indicate that the segmental motion for HBPS is less cooperative than that of the linear PS, probably due to a lack of intermolecular chain entanglements in HBPS.

A spin-coating method with the aid of selective solvents has been used to construct multilayer structures for organic devices under the assumption that the solvents do not invade a preformed structure. To confirm the assumption, we examined the interfacial width (lambda(i)) of model polymer bilayers, composed of polystyrene and perdeuterated poly(methyl methacrylate), prepared by spin-coating and flotation methods. Neutron reflectivity measurements revealed that the lambda(i) value was larger for the spin-coating method than for the flotation method. These results cast doubt on the validity of the assumption. This knowledge should be kept in mind when this method is applied to construct multilayer structures.

Density profiles of a perdeuterated poly(methyl methacrylate) (dPMMA) film spin-coated on a substrate in water, hexane, and methanol, which are "nonsolvents" for dPMMA, were examined along the direction normal to the interface by specular neutron reflectivity (NR). The interfaces of dPMMA with the liquids were diffuse in comparison with the pristine interface with air; the interfacial width with water was thicker than that with hexane. Interestingly, in water, the dPMMA film was composed of a swollen layer and the interior region, which also contained water, in addition to the diffused layer. The interface of dPMMA with hexane was sharper than that with water. Although there were slight indications of a swollen layer for the dPMMA in hexane, the solvent molecules did not penetrate significantly into the film. On the other hand, in methanol, the whole region of the dPMMA film was strikingly swollen. To conserve mass, the swelling of the film by the nonsolvents is accompanied by an increase in the film thickness. The change in the film thickness estimated by NR was in excellent accord with the results of direct observations using atomic force microscopy (AFM). The modulus of dPMMA in the vicinity of the interfaces with liquids was also examined on the basis of force-distance curves measured by AFM. The modulus decreased closer to the outermost region of the film. The extent to which the modulus decreased in the interfacial region was consistent with the amount of liquid sorbed into the film.

Microphase-separated structures of a poly(deuterated styrene-block-2-vinylpyridine) (dPS-b-P2VP) block copolymer in thin films were studied by neutron reflectivity (NR) and transmission electron microtomography (TEMT). The dPS-b-P2VP block copolymer shows a cylindrical morphology in the bulk state. The block copolymer was spun-coated on a Si substrate, which was extensively annealed (170 °C for 14 days) before the NR experiments. The annealed thin film showed a featureless NR profile, the reflectivity monotonically decreased with the increasing scattering vector along the depth direction of the thin film, qz. The portion of the dPS-b-P2VP block copolymer thin film used in the NR experiment was examined by TEMT, from which a three-dimensional (3D) morphology of the block copolymer thin film was successfully obtained. The 3D image clearly showed that the microphase-separated structure inside the thin film had a cylindrical morphology with some order along the depth, but almost no in-plane order. In order to...

Morphology for films of poly(methyl methacrylate) with various molecular weights was observed before and after methanol immersion by using atomic force microscopy so that the effect of chain entang...

A novel approach to surface modification of polymer films is proposed on the basis of graft polymerization initiated from photosensitizers attached to hyperbranched polymers which are localized at the film surface.

Density profiles of a perdeuterated poly(methyl methacrylate) (dPMMA) film spin-coated on a substrate in water (H2O) and deuterated water (D2O) were examined along the direction normal to the interface by specular neutron reflectivity (NR). Although H2O and D2O were typical non-solvents for dPMMA, their interfaces were more diffuse than the air/dPMMA interface due to the swelling caused by the sorption of H2O and D2O molecules. An isotopic effect on aggregation structure of the dPMMA film in water was also discussed.