Kobunshi - Vol. 59, No. 5 (May, 2010)

Hot Topics

Vol. 59, No. 5, May (2010)

Polymeric Porous Scaffolds for Tissue Engineering
Guoping CHEN
Biomaterials Center, National Institute for Materials Science

Porous scaffolds have been used as temporary supports in tissue engineering to control cell functions and to promote the formation of new tissues and organs. We have developed a number of porous scaffolds from biodegradable synthetic polymers and naturally derived polymers. Funnel-like porous scaffolds were prepared by using embossing ice particulates as a template. Highly interconnected collagen meshes were prepared by using poly(DL-lactic-co- glycolic acid) knitted mesh as a template. Hybrid scaffolds were prepared by forming sponges of naturally derived polymers in the openings of a mechanically strong synthetic polymer skeleton. These biodegradable porous scaffolds have been used for three-dimensional cell culture and demonstrated as being useful for tissue engineering of a variety of tissues such as skin, cartilage and bone. PMF Preprints, Japan 2009, 18, 5.

Nano-Gel Photopolymer for Phase-Rock Collinear Holographic Memory
Junichi IKEDA
Kyoeisha Chemical Co., Ltd.
Nano-gel photopolymer (NGPP) for phase-lock collinear holographic memory as the next generation memory system was developed. Because of the extremely low noise, both the intensity and phase information can be recorded in the NGPP. NGPP consists of nano scale phase separated soft and hard segment matrix. In the soft segment, the fringe was formed as aggregates of the high refractive index oligomer. It takes the shape of a nano scale flask which marks the first time of successfully observing TEM images of NGPP by the phase contrast electron microscope. Before and after 10,000 multiplexing recordings/ replayings with a plane wave tester, noise levels stayed low. The figure shows results of light scattering noise measurements, exhibiting the same level as same as a standard PC substrate. PMF Preprints, Japan 2009, 17, 23.

New Applications of Fiber and Film Using Low Isotactic Polypropylene
Toshitaka KANAI
Performance Materials Laboratories,
Idemitsu Kosan Co., Ltd.
Novel polypropylene showing very low isotacticity, low modulus and narrow molecular weight distribution (LMPP) was obtained using the specific C2 symmetric metallocene complexes. Spunbond non-woven fabrics using this novel polypropylene had high elastic recovery and reached 85% using bi-component (BICO) or multi- layered structure under high line speed. A small amount of very low tacticity polypropylene added to standard PP improved the spinnability and could produce very fine denier and soft touched non-woven fabrics. It has a potential of reducing non-woven fabrics weight. It was also added to the biaxially oriented polypropylene grade (BOPP). Blending of very low tacticity PP to BOPP influenced spherulite size and lamella thickness and decreased the yield stress of stretching force and the stress at the high stretching strain without reducing melt temperature which improves film thickness uniformity and prevents film break during the stretching process. PMF Preprints, Japan 2009, 18, 29.

Carbon Nano-Particle Composite Actuators
Midori KATO and Masayoshi ISHIBASHI
Hitachi, Ltd., Central Research Laboratory
We have developed electroactive -polymer actuators using a carbon nano-particles (CNP) composite, which consists of CNP and organic polymer. We elaborated two typical CNP composite actuators by optimizing the components of the composite; one operates in the electrolyte solution, and the other can operate in air. Although the compositions of the materials of both actuators are almost the same, the actuation principles are completely different. The former works by a charge that accumulates in the electric double layer formed on minute particle surfaces. The latter utilizes thermal expansion induced by Joule heating. The actuators we have developed are light weight and flexible, and allow for ease of processing therefore these can be used for various application, such as advanced robots, medical devices and tactile interface devices. PMF Preprints, Japan 2009, 18, 178.

Active Matrix Electronic Paper with Silver Electrodepositon
Noriyuki KOKEGUCHI
Materials Technology R&D Laboratories
Konica Minolta Technology Center, INC.
Many technologies relating to the electronic paper and the related products have been developed or proposed. But a major difference between the achieved level of the electronic paper and merits of the regular paper still exists, and many technological problems are yet to be solved. We focused on improving the display quality of electronic paper documents. We developed an electronic paper of 3.5 inches, driven by an active-matrix using silver electrodeposition, which in comparison with other electronic papers, is exhibiting the highest level of whiteness in the world. This electronic paper has a white reflectivity of over 60%, approaching that of copy paper, and a contrast ratio of at least 10:1, which results in a visibility equivalent to copy paper. PMF Preprints, Japan 2009, 18, 160.

High-Performance Dye Based on Phenolic Resin Oligomer
Kentaro SUMI and Gen-ichi KONISHI
Department of Organic and Polymeric Materials,
Graduate school of Science and Engineering, Tokyo Institute of Technology
We designed a high-performance fluorescent dye with a high absorption coefficient and quantum yield; the dye is based on a phenolic resin oligomer. The starting material (phenolic resin oligomer) is 1,1,2,2-tetrakis (4-hydroxyphenyl)ethane, which can be easily synthesized from an acid-catalyzed phenol with glutaraldehyde. The new dye has four phenylpyrene chromophores with high density and each chromophore is arranged in a three-dimensional topology. Using this structure as a building block, an intramolecular energy and/or an electron transfer in chromophores can be prevented; therefore, the photoluminescence property of the chromophores can be improved in comparison with that of a monomer. This phenol oligomer is a promising candidate for a building block of photofunctional materials. PMF Preprints, Japan 2009, 18, 174.

Fluorescent UV-Curable Resins for Facile Visualization of UV-Nanoimprinted Resist Patterns
Kei KOBAYASHI, Shoichi KUBO, and Masaru NAKAGAWA
Institute of Multidisciplinary Research for Advanced Materials (IMRAM),
Tohoku University
UV nanoimprint lithography (UV-NIL) has recently attracted a lot of attention as a nano/micro fabrication tool to make high resolution patterns at high throughput and low cost. A simple method of product inspection for detecting pattern defects is required for UV-NIL to be accepted in industry. We have recently developed fluorescent UV-curable resins for the purpose. Pattern defects arising from particle contamination, unleveled residual layer thickness, and incomplete resin filling due to bubble trap and capillary bridge in addition to resin adhesion to a mold surface could be visualized. The fluorescent UV-curable resins have a potential for allowing us to manage product quality in a wide-size range from a microscopic molecular scale to a macroscopic wafer/substrate scale. PMF Preprints, Japan 2009, 18, 66.

CO2 and CS2 as Resources for Functional Polymers
Bungo OCHIAI
Graduate School of Science and Engineering, Yamagata University
CO2 and CS2 are abundant and inexpensive non-petroleum compounds. Although these C1 chemicals have not been resources widely employed, using them as sources for functional polymers is recently of interest. CO2 can be transformed to cyclic carbonates via the reaction with appropriate epoxides under mild conditions. Polyaddition of bifunctional cyclic carbonates and diamines yields polyhydroxyurethanes. Reactions of polyhydroxyurethanes gave various functional polyurethanes such as functional cross-linkers. CS2 can be transformed to cyclic dithiocarbonates as well. Highly refractive polymers and rare-metal absorbing polymers were synthesized based on the reaction of cyclic dithiocarbonates with amines yielding mercapto-thiourethanes. The first three-component polyaddition with quantitative atom-economy was attained through the transformation of the reaction modes from nucleophilic to radical reactions. PMF Preprints, Japan 2009, 18, 176.

Development of Thermo-Responsive Magnetic Nano Particles (Therma-Max) and their Application to Biotechnology
Noriyuki OHNISHI
Magnabeat Inc.
Recently, we were successful using NIPAM (N-i-Propylacrylamide) and NAGAM (N-Acryloyl Glycine amide) in the composition of 2 types of thermo-response polymer-immobilized magnetic nano-particles (average size <100nm) which show lower critical solution temperature (LCST) or upper critical solution temperature (UCST) respectively. The thermo-response polymer-fixed magnetic nano-particles were biotinylated to carry out the co-polymerization of the biotin derivative (N-methacryl-N'-biothinyl propylenediamine,) to NIPAM or NAGAM, respectively. This time, the application in the biotechnology of magnetic separation for entities from life science (protein, DNA and RNA, cell, etc.) is reported using these 2 types of biotinytized thermo-response polymer fixed magnetic nano-particles. PMF Preprints, Japan 2009, 18, 1.