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Research paper : Development of massive synthesis method of organic nanotube toward practical use (M. Asakawa et al.)−171 Synthesiology - English edition Vol.1 No.3 (2009) The fourth phase was an extremely important aspect of the potential practical application of the organic nanotubes. Although the safety assessment items differed from field to field, we selected common features in the initial phase to motivate the manufacturers to employ our organic nanotubes.3 Functions to be realized and synthesiological method3.1 Main elemental technologiesWe selected the following five elemental technologies for the practical application of organic nanotubes: (1) technology for the molecular design and synthesis of amphiphilic molecules for the fabrication of organic nanotubes using naturally occurring, recyclable raw materials; (2) technology for the efficient synthesis of organic nanotubes through the self-assembly of amphiphilic molecules; (3) selection of elemental technologies necessary for utilization development; (4) selection and implementation of safety assessment items to widely promote organic nanotubes; and (5) selection of a timely technological transfer policy and appropriate research management for product realization research.3.2 Integrated system and realized functionEach elemental technology should ideally proceed sequentially, from (1) molecular design and synthesis to (2) self-assembly to (3) utilization development to (4) safety assessment and then to (5) product realization. In actual research, however, things almost never progress in an orderly manner. For the progress of an elemental technology in actual research, planning of the working hypothesis and verification through experiment are repeated between stages (1) and (2). New knowledge is obtained through such repetition (Type 1 Basic Research); the research process moves on to stages (3) and (4) when satisfactory answers are obtained. In our R&D study for the practical applications of organic nanotubes, after developing the elemental technology in stage (3), heteronomous factors increased because the process progressed to a phase in which goal achievement became a prime motive (Type 2 Basic Research). Specifically, technology was refined further by feedbacks through fusion with conventional technologies to meet demand, comparison with conventional competitive materials, and managerial decisions (Figure 4). For stage (4), existing information using conventional assessment technologies and comparable assessment methods should be selected at the initial phase because there is very little room for the development of new technology. When utilization development progresses in stage (3) and demand arises in new fields, new safety assessment methods must be developed in stage (4) in collaboration with practitioners in relevant fields.4 Research results4.1 Molecular design and synthesis of amphiphilic molecules for the fabrication of organic nanotubesA few years ago, we discovered a way to selectively form organic nanotubes through self-assembly in water using cardanol/glucose-based amphiphilic molecule 1 synthesized from glucose and cardanol extracted from cashew nut shells.[13] The characteristic function of this amphiphilic molecule was the selective formation of tubular structures in water; nevertheless, the thermal stability was low, with a gel–liquid crystal phase transition temperature in water of 40 °C. In other words, when the sample was heated to 40 °C, the structure changed from tubes to liposome-like spheres; we determined that we could not put these organic nanotubes to practical use. Therefore, we designed and synthesized the amphiphilic molecule 2, in which hydrogen bonding can occurs at the amide group, by replacing the benzene ring linking the glucose unit and the alkylene chain in amphiphilic molecule 1 with an amide unit. As expected, the organic nanotubes created from the amphiphilic molecule 2 was much more heat-stable than molecule 1, with its gel–liquid crystal phase transition temperature being ca. 70 °C[14]. Although we had solved the issue of thermal stability by using the (17)−Fig. 4 Conceptual representation of the integration of the main elemental technology for the development and application of organic nanotubes.Fig. 5 Molecular design for practical application of amphiphilic molecules.AISTCompany(1) Molecular design and synthesis technology(2) Self-assembly technology(3) Practical use development(4) Safety assessment technology(5) Product Realization technology3OHHOHOOOHHNO11-Cis9-CisOHHOHOOOHHNOOHHOHOOOHHNOO12ThermalstabilityLowercost

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