Monomeric Unit | ScienceGate

The CD spectra of aqueous solutions of homopolymeric sodium oligogalacturonates and D-galacturonans of polymerization degree n = 1-64, as well as lower calcium oligogalacturonates (n = 1-5) were measured. Chiroptic properties were correlated with the polymerization degree in terms of optical superposition of monomeric unit increments. Interpretation of obtained data, respecting further physicochemical properties entitles to conclude that the conformation of macromolecules of D-galacturonan in solution is close to helical structure.

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Stereoselective Synthesis of the Monomeric Unit of SCH 351448

European Journal of Organic Chemistry ◽

10.1002/ejoc.200600106 ◽

2006 ◽

Vol 2006 (12) ◽

pp. 2777-2785 ◽

Cited By ~ 11

Author(s):

J. René Backes ◽

Ulrich Koert

Keyword(s):

Stereoselective Synthesis ◽

Monomeric Unit ◽

Sch 351448

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Total Synthesis of the Monomeric Unit of Lomaiviticin A

Journal of the American Chemical Society ◽

10.1021/jacs.0c10660 ◽

2020 ◽

Vol 142 (47) ◽

pp. 20201-20207

Author(s):

K. C. Nicolaou ◽

Qifeng Chen ◽

Ruofan Li ◽

Yasuaki Anami ◽

Kyoji Tsuchikama

Keyword(s):

Total Synthesis ◽

Monomeric Unit

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Dynamic Mechanical Properties of a Number of Elastomers and Related Polymers from 4 to 250° K

Rubber Chemistry and Technology ◽

10.5254/1.3542884 ◽

1972 ◽

Vol 45 (4) ◽

pp. 1033-1042

Author(s):

R. J. Morgan ◽

L. E. Nielsen ◽

R. Buchdahl

Keyword(s):

Mechanical Properties ◽

Low Temperature ◽

Bond Angle ◽

Dynamic Mechanical Properties ◽

Molecular Packing ◽

Butyl Rubber ◽

Monomeric Unit ◽

Dynamic Mechanical ◽

Young’S Moduli ◽

Cis And Trans

Abstract Young's modulus and mechanical damping have been measured down to 4° K for cis- and trans-polybutadienes, cis- and trans-polyisoprenes, butyl rubber, and random SBR copolymers. Trans-polybutadiene has two large damping peaks below Tg, trans-polyisoprene one peak, while the cis-polymers and butyl rubber show either no damping peaks or only very small ones below Tg. The low-temperature damping peaks of the trans-polymers might be explained by a type of crankshaft motion and by a special motion of the trans-monomeric unit which involves a simultaneous vibration and bond angle deformation. The high Young's moduli of the polybutadienes compared to the polyisoprenes and the SBR copolymers are explained by the good molecular packing of the polybutadienes.

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