On the Crystal Structure of cis-1,4-Poly(2,3-dimethyl-1,3-butadiene)

• Published in: Macromolecular rapid communications. Vol. 24; no. 5-6; pp. 392 - 396
• Main Authors: Pirozzi, Beniamino, Napolitano, Roberto, Petraccone, Vittorio, Esposito, Simona
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.04.2003; WILEY‐VCH Verlag; Wiley
• Subjects: Applied sciences; conformational analysis; Exact sciences and technology; molecular mechanics; Organic polymers; Physicochemistry of polymers; Properties and characterization; Structure, morphology and analysis; WAXS; Butadiene derivative polymer; Structural model; Unsaturated polymer; Experimental study; Modeling; Crystalline structure; Cis stereoisomer
• ISSN: 1022-1336; 1521-3927
• DOI: 10.1002/marc.200390056

Models for the crystal structure of cis‐1,4‐poly(2,3‐dimethyl‐1,3‐butadiene) are elucidated by the joint use of molecular mechanics and WAXS. The chain conformation can be predicted by using different sets of potential functions. A model of crystal structure calculated by molecular mechanics has been refined in order to find the best accordance with the experimental X‐ray powder spectra. Another model is proposed to explain a few minor discrepancies between the calculated and the experimental WAXS powder spectra. Portion of the chain of cis‐PDMBD, containing two monomer units with indications of the symmetry elements of the tci line repetition group, and of the bond and torsion angles of the backbone, which are independent variables.