We have developed a methodology based on ab initio molecular orbital calculations, NMR experiments, and the rotational isomeric state (RIS) scheme for predicting conformational characteristics and configurational properties and elucidating structure-property relationships of polymers. We have applied the methology to various polymers including heteroatoms such as nitrogen, oxygen, silicon, phosphorus, sulfur, and selenium in the backbone. In rent years, we have treated such green polymers as [biodegradability] poly(glycolic acid), poly(lactic acid), poly(2-hydroxybutyrate), poly((R)-3-hydroxybutyrate), poly((R)-3-hydroxyvalerate), poly(ethylene succinate), and poly(butylene succinate), [carbon dioxide fixation] poly(ethylene carbonate), poly(propylene carbonate), and poly(cyclohexene carbonate). Furthermore, we have investigated polymer crystals with density functional theory calculations under periodic boundary conditions and obtained the following information: optimized structures (lattice constants and atomic coordinates); interchain cohesive energy; vibrational spectrum; thermodynamic functions; phase transition temperature; crystalline modulus. In our presentation, we will report the summary of the recent studies including unpublished results.

Yuji Sasanuma received bachelor’s (1980) and master’s (1982) degrees in engineering from Tokyo Institute of Technology (Department of Polymer Chemistry), worked in Toray Industries Inc. (Toray Research Center) (1982-1988), returned to Tokyo Institute of Technology as a research associate (1988-1993) of Prof. Akihiro Abe, received doctor’s degree in engineering (1992), worked in National Institute of Materials and Chemical Research (Department of Polymer Physics) in Tsukuba as a researcher (1993-1994) and a senior researcher (1994-1997), and moved to Chiba University as an associate professor (1997-). For details of his career and research interests, please see his home page: http://www.sasanuma.org/