Structure and properties of oligomeric n,n′-diarylureas

Autor:	V.F. Matyushov, G.I. Khmelenko, A.V. Krolenko, Yu. S. Lipatov
Rok vydání:	1989
Předmět:	chemistry.chemical_compound Crystallography Materials science Liquid state Character (mathematics) chemistry Diol General Engineering Structure (category theory) Glass transition Amorphous solid
Zdroj:	Polymer Science U.S.S.R.. 31:1393-1399
ISSN:	0032-3950
DOI:	10.1016/0032-3950(89)90171-8
Popis:	Structure and properties of segmented oligomeric polyetherurea-urethanes of ABA structure, consisting of flexible oligoether or oligodiene blocks B and rigid urethane-urea blocks A was studied. The oligomers were found to be amorphous and microheterogeneous. The character of the starting oligomeric diol is decisive for the extent of microphase segregation of rigid and flexible blocks. The existence of two high-temperature transitions has been established, the first being attributed to glass transition in the rigid urea-urethane blocks. Survival of the heterophase structure in the liquid state is postulated; the second transition is important for the existence of heterophase structure in liquid oligomers.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::c73c9069d83ca2edca2abc014713104c https://doi.org/10.1016/0032-3950(89)90171-8 Zobrazit plný text záznamu