Materials Science and Engineering Laboratories

Laboratory for Novel Polymer Materials

Basic Information


Professor Kohji Tashiro / Post-Doctoral Taiyo Yoshioka / Post-Doctoral Daisuke Tahara / Post Doctoral Nguyen To Hoai / Researcher Hiroko Yamamoto


Study of structure-property relationship of polymers

The structure-property relationship of synthetic polymers is clarified from the molecular level to the nanoscale level by means of the various types of techniques such as X-ray diffraction, vibrational spectroscopy, computer simulation, etc. The novel polymer materials with more excellent properties will be developed on the basis of the thus accumulated knowledge.

Research Themes

Accurate structure analysis of polymer crystals using synchrotron X-ray and neutron radiations
Molecular motion and intermolecular interactions in polymer crystals
Experimental and theoretical evaluations of ultimate properties of polymers
Clarification of structural evolution process of polymers during the crystallization phenomena



X-ray structure analysis of polyoxymethylene

 Clarification of electron density distribution of polymer chain


Polymer materials, indispensable in our everyday life, are expected to be developed furthermore in a variety of application fields.  It has been, however, told sometimes negatively that all the polymers with excellent properties have been considered out already and no new polymers can be produced anymore as the materials useful for our livings.  How can we produce novel polymer materials with more excellent properties ?  This still important but hard research theme must be solved by clarifying the relationship between the structure and properties of many conventional polymers and by extracting the general rules from these empirical relationships.  Unfortunately, however, the clarification of structure-property relationship is quite difficult even for such multi-purpose polymers with relatively simple chemical structures as polyethylene, polyoxymethylene, nylon etc.  In the period of 2005 - 2009, our laboratory launched the project for the accurate analysis of structure-property relationship of polymer materials with the financial supports by the ministry of education, culture, sports, science and technology, Japan, Toyota Motor Corporation, and Toyota School Foundation.   The renewed project was started from 2010 for 5 years plan, which is the International Project on the Basic Research Promotion for the Development of Highly-Controlled Multi-Purpose Polymer Materials ” of “the Strategic Project to Support the Formation of Research Bases at Private Universities” of the Ministry of Education, Culture, Sports, Science and Technology, Japan.  These projects have been activated by building up the research center for polymer science.  The various kinds of experimental equipments were introduced into the center and the collaboration system was organized well between our university and the polymer-related companies as well as the other universities and research institutes in the world. 
The strategies of the research project are summarized as below.

(1) Detailed analysis of complicated hierarchical structure of polymer materials
The details of hierarchical structure including molecular chain conformation, crystal structure, amorphous structure, higher-order structure of stacked lamellae and spherulitic structure are investigated by developing the experimental techniques based on X-ray diffraction, neutron diffraction, electron diffraction, infrared and Raman spectroscopy, and so on and also by combining these data with the computer simulation results and the theoretical calculations.  Some new software are developed for the quantitative data analysis of X-ray diffraction data and vibrational spectroscopic data. 

(2) Investigation of phase transitions of crystalline region of polymers
Structural changes occurring in the phase transitions of crystalline region, which are induced by changing temperature or by applying an external stress, for example, are investigated in relation with the changes in physical properties.

(3) Clarification of structural evolution process in crystallization phenomena
Structural regularization of polymer chains during the crystallization phenomena are investigated concretely through the time-dependent rapid measurements of synchrotron X-ray scatterings, vibrational spectra and so on.  The factors necessary for controlling the higher-order structure (and the physical properties) are extracted from these data.

(4) Clarification of structure-property relationship of polymers from the various levels
Ultimate values of the physical properties of polymer crystals are predicted theoretically on the basis of the structural information derived from the X-ray diffraction analysis and the interatomic interaction parameters obtained from the vibrational spectroscopic analysis.  The physical properties of bulk polymer materials are also interpreted by combining the thus-derived properties of crystalline and amorphous regions.

(5) Molecular design and production of novel polymer materials with excellent properties
By extracting various empirical rules derived from the above-mentioned structure-property relationship, it may be possible to make a molecular design of novel polymer substances with more excellent properties than the conventional polymers.  In a lucky case we might be able to synthesize these polymers actually and check their physical properties for the applications.

(6) Dispatch of information and technologies to the world
The technologies and concepts which are derived in this project and useful for the study of structure-properties relationship of polymer materials will be dispatched to the polymer researchers of the world.

(7) International collaborations with research organizations of foreign countries
The above-mentioned research themes have been challenged also by building up the teams with overseas researchers working in the common fields, resulting in the acceleration of research exchange with them and the increase in the chance to invite the PhD course students into our university.
In this way, our research project plans to clarify the structure-property relationship of polymers systematically and totally from the microscopic to macroscopic levels, and it should give great impacts to the research fields of polymer science.

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