Mechanism of conformation change-overs in polymer chains

Priss, L. S.; Gamlitskii, Yu. A.

doi:10.1016/0032-3950(83)90093-x

Cited by 3 publications

(2 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Later, a mechanism was proposed for the conformational restructurings which was free of these defects (refs. 61 Transition to a stable conformation can occur as a result of a redistribution of the angles of rotation around the simple units to adjacent sections of the chain. In this case the section changing its structure may change in length (shorten or stretch).…”

mentioning

confidence: 99%

Studies in Rubber Physics

Priss¹

2002

International Polymer Science and Technology

View full text Add to dashboard Cite

The physics of rubber may be arbitrarily divided into two parts: the physics of unfilled rubbers, or the physics of network polymers, and the physics of filled rubbers. It is true of course that the former forms the basis of the latter, which from a practical point of view is more interesting, since in the overwhelming majority of cases in industry only filled compounds are employed. But they are very complex systems, difficult to describe theoretically, and therefore despite the fact that a large number of studies on them have been carried out, in monographs on the mechanical properties of polymers only one chapter is devoted to them (refs. 1 and 2). In the present survey our attention is also concentrated mainly on unfilled rubbers, since all the physical phenomena studied in unfilled rubbers also occur in filled rubbers, but in a considerably more complicated fashion. Also, we shall not examine problems such as crystallisability and strength, which have been investigated in detail at the All-Union Institute of Synthetic Rubber and the Rubber Research Institute (refs. 3 and 4). The modern study of the physics of network polymers began in the 1940s. During this period, the beginning of which marks the emergence of the theory of high elasticity, which overtook the old colloid chemistry ideas concerning the nature of rubber elasticity (ref. 5), rubber physics achieved its great successes both in the experimental and in the theoretical fields. Let us note just a few key moments of this development. 1. The classical theory of high elasticity: 1936-1943 (refs. 6-10). 2. The phenomenological theory of rubber elasticity. The Mooney-Rivlin equation; 1940-1948 (refs. 11 and 12). 3. The accumulation of data on the dependences of the elasticity constants in the Mooney-Rivlin equation on various factors; 1953-1977 (refs. 13-15). 4. The molecular theory of viscoelastic properties of polymers; 1948-1953 (refs. 16 and 17). 5. Formulation of the principle of temperature-time reduction; 1955 (ref. 18) 6. Explanation of the role of the energy component of stress in the deformation of polymers; 1955 (ref. 19). 7. Synthesis of partially deuterated polymers and the study of their structure by low-angle scattering of slow neutrons; 1960 (ref. 2). 8. Formulation of the hypothesis of topological (steric) interactions; 1957-1967 (refs. 20 and 21). 9. Synthesis (using end mechanism) of polymer networks with a well-defined structure; 1970 (refs. 22 and 23). 10. Division of the stress in the transitional zone from the high-elastic to the glassy state into entropy and energy components; 1980-1993 (refs. 24 and 25). 11. Study of the conformational restructurings in polymer chains; 1961-1986 (refs. 26 and 27). These references in no way exhaust all of the studies published on each of these trends, but in most cases simply refer to the best known studies. The time frames are also to some extent arbitrary. Studies on many of these topics are ongoing at the present time.

show abstract

mentioning

confidence: 99%

Studies in Rubber Physics

Priss¹

2002

International Polymer Science and Technology

View full text Add to dashboard Cite

show abstract

“…Οι Kopusow και Sharkow [45] πρότειναν προς τούτο μία μέθοδο όπου με αμινόλυση οι δεσμοί αυτοί ανάγονται στις αντίστοιχες υποκατάστατες ουρίες και έτσι το περιεχόμενο των αλλοψανικών και διουρικών ομάδων προσδιορίζεται στα 1655 cm"' όπου βρίσκεται η ταινία του χαρβονυλίου της ουρίας. Η μέθοδος αυτή, όμως, δεν είναι ακριβής[43,46]. Παρόμοιες δυσκολίες συναντώνται κατά τον προσδιορισμό όμως, -όπως και μ Ια άλλη των Furukawa και Yokoyama [51]-αποδεικνύεται ανεπαρκής, όταν πρέπει να προσδιορισθούν μικρές συγκεντρώσεις διουρικών και/ή αλλοφανικών ομάδων σε σχέση με μεγάλες συγκεντρώσεις ισοκυανικών ομάδων.…”

unclassified