Cocrystallization and Crystalline Transformations in Copolymers of Butene-1 and Olefins (Special Issue on Polymer Chemistry, III)
Year: 1966
Type: editorial
Abstract: The crystallization phenomena in olefin copolymers due to isomorphism of monomer units are discussed from the point of chain conformation.Copolymerizations of butene-1 and 4methyl-1-pentene, 3-methyl-1-butene, styrene and propylene were carried out with stereospecific catalytic system.An interesting feature of the copolymers of butene-1 and 4-methyl-1-pentene or 3-methyl-1-butene is an ability to crystallize in type of the modification II of polybutene-1.It is reasonably assumed that the modification II which is usually less stable than I in butene-1 homopolymer is stabilized owing to incorporation of those comonomer units into the crystal lattice of the modification II.On the contrary, it is observed that styrene or propylene units in a copolymer promote the transformation from the Form II to I.These facts imply that cocrystalline copolymer can not be formed from copolymerization of butene-1 and styrene or propylene.It is likely to account for those facts by viewing the chain conformations in the crystals of each homopolymer.Crystallizability and variations of lattice parameters in crystal phases are studied in copolymers of butene-1 and 4-methyl-1-pentene.It is found that this system is crystalline over the whole range of monomer composition, and its crystal lattice constant is changed in relation to the composition.The physical properties of those copolymers are discussed, correlating with their cocrystallization behavior.
Language: English
Subfield: Polymers and Plastics
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W61300446