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Poly(γ-glutamic acid) (PGA) is a biopolymer produced by Bacillus spp. via the γ-amide linkages of d- and/or l-glutamate. PgsB, PgsC, and PgsA are the minimum protein set required for PGA production in B. subtilis, and PgsE improves PGA productivity. Analysis by size-exclusion chromatography combined with multiangle laser light scattering revealed that the molecular weight of PGA was M_w = 2,900,000 g mol⁻¹ or predominantly M_w = 47,000 g mol⁻¹ in preparations derived from B. subtilis cells with or without pgsE, respectively. PgsE may be required to increase the apparent molecular weight of PGA.

The crystalline phase of PVDF film prepared by spin-coating changes both of the polymer–solvent interaction and the evaporation rate. In the much solvent remained state, the crystalline phase changes in the order of α, γ and β phase with increasing the dipole moment of solvent. In the solvent-evaporated state, the crystalline phase of PVDF and solvent with higher dipole moment system changes in the order of β, γ and α phase with increasing the solvent evaporation rate, whereas the PVDF and solvent with lower dipole moment system forms into α phase regardless of the evaporation rate.

A bis(tert-butyl) isophthalate (B-IP) was utilized as a dissolution inhibitor in chemically amplified three-components resist. In extreme ultraviolet (EUV) exposed area, tert-butyl groups of B-IP were decomposed by the effect of protons generated from photo-acid generator, and B-IP was converted to a carboxylic acid, being played a role of dissolution promoter. Furthermore, B-IP was acted as a plasticizer in the resist and the protons were diffused through the resist easily. The resist containing B-IP was improved its sensitivity and dissolution contrast, although the properties are a relation of trade-off.

Control of the crystalline structure of poly(vinilydene fluoride) (PVDF) in a PVDF/poly(methylmethacrylate) (PMMA) blend were analyzed by varying the polymer blend ratio (PVDF/PMMA=60/40, 70/30 and 80/20 wt%) and the heat-treatment temperature (160–210 °C) just after the polymer melt. PVDF (form I) was limitedly obtained by heat treatment at 185 and 190 °C after blending PVDF/PMMA 70/30 wt%. The samples produced under other conditions indicated PVDF (form II). We assumed that PVDF crystalline structure became PVDF (form I) according to decrease of the crystallization rate by the highest compatibility between PVDF and PMMA.

The effect of cooling rate after polymer melting on the electrical properties of high-density polyethylene (HDPE)/Ni conductive polymer composites was investigated. Ni particles in HDPE/Ni composites are localized into the amorphous matrix of HDPE. Therefore, conductive paths are formed effectively by increasing HDPE crystallinity. It was found that the resistivity at room temperature of slowly cooled samples is lower than that of quenched samples because the crystallinity of HDPE in slowly cooled samples is higher than that in quenched samples.

In this paper, we have provided the first conclusive evidence that the Ni particle dispersed poly(methylmethacrylate) (PMMA) composites, which do not exhibit melting phenomenon, exhibit the positive temperature coefficient (PTC) effect when Ni content were 20 and 25vol.%. In particular, the composite with Ni content of 25vol.% exhibited PTC effect comparable to that of composites composed of crystalline polymer, and it demonstrated conductor/insulator transition. We assumed that these composites have few conductive paths, and so disconnection of conductive path occurred from slight volume expansion of PMMA by temperature rising.

The solvent evaporation rate in the production of three types of poly(vinylidene fluoride) (PVDF) crystalline structures by using the solvent casting method was quantified. The PVDF crystalline structures were predominantly determined by solvent evaporation rate. PVDF (form I) was obtained when the solvent evaporation rate was <0.0001 g min⁻¹, PVDF (form II) was obtained when the solvent evaporation rate >0.2 g min⁻¹ and PVDF (form III) was obtained when the solvent evaporation rate was from 0.03 to 0.00058 g min⁻¹.

This paper demonstrates a simple method for the preparation of poly(vinylidene fluoride) (PVDF) films using the antisolvent addition method. The antisolvent addition method was performed by immersing PVDF solution-casted substrates into the antisolvent for PVDF at room temperature for a few minutes. After immersing and drying for a few hours, a PVDF film was easily obtained. Then, the crystalline structure of the resulting PVDF film was changed in the order of α, γ and β phases with increasing dipole moment of the solvent.