Reference

Kinetic studies on cationic ring-opening polymerization of 2-phenyl-1,2-oxaphospholane

Kinetic studies on cationic ring-opening polymerization of 2-phenyl-1,2-oxaphospholane.Some chemicals with cas registry numbers like 74-88-4 and 16324-17-7 are also used. Kobayashi, Shiro; Suzuki, Masato; Saegusa, Takeo (Fac. Eng., Kyoto Univ., Kyoto 606, Japan). Macromolecules, 17(1), 107-10 (English) 1984. CODEN: MAMOBX. ISSN: 0024-9297. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Section cross-reference(s): 67 The kinetics of the cationic ring-opening polymn. of 2-phenyl-1,2-oxaphospholane [16324-17-7] were detd. by 31P-NMR, and the rate consts. and activation parameters of propagation were calcd. Polymn. by CF3SO3Me [333-27-7] proceeded by cyclic phosphonium compds., while polymn. by MeI [74-88-4], PhCH2Br [100-39-0], or PhCH2Cl [100-44-7] involved covalent alkyl halides. The propagation rate decreased in the order MeI, CF3SO3Me, PhCH2Br, and PhCH2Cl; the 1st example of covalent intermediate more reactive than a phosphonium compd. .

Cationic polymerization of 1,4,6-trioxaspiro[4

Cationic polymerization of 1,4,6-trioxaspiro[4.4]nonane. Matyjaszewski, Krzysztof (Cent. Mol.In this study， 176-37-4 and 29830-67-9 are also used. Macromol. Stud., Pol. Acad. Sci., Lodz 90-362, Pol.). J. Polym. Sci., Polym. Chem. Ed., 22(1), 29-40 (English) 1984. CODEN: JPLCAT. ISSN: 0449-296X. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Cationic polymn. of 1,4,6-trioxaspiro[4.4]nonane [176-37-4] with Me3O+SbF6- [29830-67-9] and MeOSO2CF3 [333-27-7] initiators was investigated. Although the obsd. rates of initiation and propagation were relatively slow, they consisted of rapid reversible elementary reactions. In 1H-NMR spectra, a broadening of the monomer signal was obsd., indicating a fast exchange between free monomer and monomer engaged in the active species. A variety of orthoester bonds was obsd. in the polymer formed at the early stages of monomer conversion. The final polymer had the structure of a linear poly(ester-ether) including two subsequent ester or ether linkages. A mechanism of polymn. was proposed, consisting of a rapid reversible opening of the rings in the monomer mol. involved in the growing species, followed by the slower opening of the second ring with formation of the ester linkage. The rings originally present in the chains apparently rearranged into the linear units intramolecularly. .