Abstract
A conformational analysis is done in order to investigate on the mobility of joints separating d helical sequences from l ones along molecules of polystyrene and polypropylene both isotactic and syndiotactic in solution or in the liquid state. Results indicate that, in the case of isotactic polystyrene, severe interactions between side phenyl rings separated by three and four monomer units play a relevant role in hindering the molecular motions necessary to move the joint. Only a coordinate torsional motion of a number of chain bonds (four) and the overcoming of a rather high energy barrier allows for the motion of the joint along the chain. Syndiotactic polystyrene and iso- and syndiotactic polypropylene show a much easier conformational situation. This may be related to the extreme slowness affecting the crystallization of isotactic polystyrene as compared to the crystallization rate of the other polymers studied. Finally a connection is proposed between results of the present analysis and a possible interpretation of the X-ray diffraction pattern recorded from the oriented (fringed micelle) crystallites contained in crystalline gels of i-PS.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
