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Aluminum tubes are efficient energy absorbing components and are widely used in the automobile industry. In the previous report, the authors investigated the influence of cross-sectional shape on axially compressed aluminum tube by numerical analysis. However, there are only a few reports on length of aluminum tube. This paper deals with the influence of axial length and reinforcing rib on dynamic axially compressed aluminum polygonal tube in order to obtain the basic data of buckling and impact resistance. A numerical analysis of the dynamic deformation process of the polygonal tube was made with a finite element method. The result shows that even if the axial length was changed, there was no difference in the trend of the load-displacement curve in each cross-sectional shape. However, the maximum load part on load-displacement curve was changed. The buckling was generated partially and the deformation was larger at the corners in each axial length and cross-sectional shape.

Lignophenol (LP)-graft-poly(2-ethyl-2-oxazoline) (POZO) was prepared to reuse lignin, an industrial waste material, and to produce novel LP-based polymer blends with poly(vinyl chloride) (PVC), poly(bisphenol A carbonate) (PC), polyvinylpyrrolidone (PVP), and polystyrene (PSt) as commodity polymers. The resulting graft polymer was soluble in various types of organic solvents such as chloroform, THF, acetone, and methanol, unlike LP. The miscibility of LP-graft-POZO with commodity polymers was measured by differential scanning calorimetry (DSC) to determine the glass transition temperatures (Tg). In the cases of the blends of LP-graft-POZO with PVC, PC, and PVP, the Tg values decreased during the second scan. Moreover, in the cases of the blends with PVC and PVP, the Tg values were not detected during the third scan. Therefore, it was inferred that LP-graft-POZO was miscible with PVC, PC, and PVP while forming single phases; in particular, the blends of LP-graft-POZO with PVC and PVP exhibited a secondary miscibility because the Tg values were not detected. Furthermore, the blend of LP-graft-POZO with PC exhibited better thermostability than LP and LP-graft-POZO. These results indicated that LP blended with POZO could be used as a polymer additive and as an adhesive to combine different polymers, organic–inorganic polymers, etc. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Hydroxyl-group-alkoxylated lignophenols (LPs) with various types of alkyl halides were prepared by Williamson ether synthesis to reutilize lignin, an industrial waste material, and make it processable. As compared with raw LP, alkoxylated LPs exhibited good organosolubility and thermal stability (temperatures at 5% loss in weight were estimated to be more than 330 °C by thermogravimetric analyses). Alkoxylated LPs could also form transparent thin films; in particular, films of hexyloxyl LPs exhibited high refractive indices (≈1.55) similar to that of bisphenol A-based poly(carbonate) (PC). Furthermore, these films had lower birefringence (

We report the direct synthesis of new functional novolacs having allyl ether (4) or bromoalkyl groups (5 and 6) in the side chain by the addition-condensation of allyl phenyl ether (1), 1-bromo-2-phenoxyethane (2) or 1-bromo-4-phenoxybutane (3) with formaldehyde. The structure of these novolacs was confirmed by Fourier transform infrared, 1H NMR and 13C NMR spectra. The number-average molecular weights (Mn) of the obtained polymers were found to be ∼1000–3000. In the case of the polymerization of 1 with formaldehyde using hydrated sulfuric acid as a catalyst, Claisen condensation did not occur with the polymerization; therefore, pure allylated novolac (4) without a phenol moiety was obtained. Thus, in this process, phenol–formaldehyde condensation proceeded under such conditions that the functional group was not affected. These polymers (4–6) have considerable potential as reactive polymers in the field of materials science. Their applications are as follows: (i) a key reaction of a latent curing system: thermal stimuli-induced Claisen rearrangement of allylated novolac to generate phenolic hydroxyl groups; (ii) vinyl ether-modified novolac (7) prepared by 1-bromoethoxy-group-modified novolac; and (iii) an amphiphilic graft-shaped polymer prepared by bromoalkyl-group-modified novolac-initiated ring-opening polymerization of 2-methyl-2-oxazoline. We report the direct synthesis of new functional novolacs having allyl ether in the side chain by the addition-condensation of allyl phenyl ether (1). In polymerization of 1 with formaldehyde using hydrated sulfuric acid as a catalyst, Claisen condensation did not occur with the polymerization; therefore, pure allylated novolac (4) without a phenol moiety was obtained. The obtained polymer (4) can be applicable for a latent curing system.

We propose a new acrylate monomer that exhibits attractive optical properties, such as good transparency, high refractive index, low birefringence, desirable optical properties, and high thermal stability. Tetraphenylethane has four aromatic rings that bind without anisotropy. A polymer with this tetraarylethane structure is expected to exhibit a high refractive index and low birefringence. In this study, we synthesized two acrylate-based polymers via radical polymerization of the acrylate monomer and methacrylate derived from 1,1′,2,2′-tetrakis(4-hydroxyphenyl)ethane. We prepared transparent coatings of the polymers on a synthetic quartz plate via spin coating and measured their refractive indices using a prism coupler. Both of the polymers exhibited a high refractive index (1.60) as compared with common PMMA (1.49) and a low birefringence, which indicated that a tetraarylethane skeleton is the preferred candidate for suppressing the birefringence of a material.