Studies on Aliphatic Polyesters. III. The Synthesis and Properties of Polylactide

Asahara, Teruzo; Katayama, Shitomi

doi:10.1246/nikkashi1898.67.6_956

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Polyesters prepared by ring opening polymerization of lactones are coming into prominence as a result of new polymerization catalysts (Chujo, Kobayashi, Suzuki, Tokyhara & Tanabe, 1967;Asahara & Katayama, 1964;Alderson, 1956;Okamura, Higashimore & Tanaka, 1962). Such macromolecules are intrinsically different from conventional polyesters (Fuller & Frosch, 1939;Fuller & Erikson, 1957) in that the chain has a sense of direction by the uniform orientation of the ester groups within the chains.…”

Section: Introductionmentioning

confidence: 99%

Crystal structure of poly-ε-caprolactone

Bittiger¹,

Marchessault²,

Niegisch³

1970

Acta Crystallogr B Struct Crystallogr Cryst Chem

317

279

View full text Add to dashboard Cite

The unit cell of poly-e-caprolactone was found to be orthorhombic with dimensions a = 7.496 + 0.002, b=4.974+0"001, c= 17.297+0-023/~ (fiber axis). The space group is P212121. This unit cell is only compatible with an extended planar chain conformation of the molecule involving two monomer residues related by a twofold screw axis in the chain direction. The P212~2~ space group and the density of 1.146 g.cm-3 indicate that the unit cell contains two chains with opposite orientation ('up' and 'down'). Intensity measurements and structure factor calculations require the rotation of the plane of the chains about their axis to an angle of 28 ° with respect to the a axis; longitudinal chain shift places the ester groups in planes perpendicular to the c axis. Folded chain single crystals with a lancet-like structure were observed by electron microscopy.

show abstract

Section: Introductionmentioning

confidence: 99%