ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Synthesis and characterization of copolymers obtained from 1,3,5-trioxane and octamethylcyclotetrasiloxane by triflic acid initiator (1996)

Rodríguez-Baeza, Mario ; Zapata, Melcy

Springer

Polymer bulletin 36 (1996), S. 173-180

add to mindlist on the mindlist

Details

ISSN: 1436-2449

Source: Springer Online Journal Archives 1860-2000

Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics

Notes: Summary A series of poly(oxymethylene-co-dimethylsiloxane) copolymers were synthesized in the molten state by cationic ring opening copolymerization of trioxane and octamethylcyclotetrasiloxane by using trifluoromethanesulfonic acid (triflic acid; CF3SO3H) as initiator. When the concentration of the oxymethylene comonomer units (-OCH2-) in the copolymers are very high, crystalline copolymers are obtained. If the concentration of the dimethylsiloxane co-units (-OSi(CH3)z-) increases, rubberlike materials are obtained. Reaction mechanisms are proposed to explain the growth of the copolymer chains. FTIR and NMR studies suggest the existence of block copolymers and block copolymers with random segments. Thermomechanical characterization of the copolymers was also carried out. This new synthetic method allows us to obtain linear copolymers containing both oxymethylene and dimethylsiloxane comonomer units in the main chain. The copolymerization of these cyclic monomers was demonstrated.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00294903

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Synthesis and structure of crosslinked poly[(methylsiloxane)-co-(oxymethylene)] copolymers (1997)

Rodríguez-Baeza, Mario ; Zapata, Melcy ; Yoshida, I. Valeria P.

Weinheim : Wiley-Blackwell

Macromolecular Rapid Communications 18 (1997), S. 747-754

add to mindlist on the mindlist

Details

ISSN: 1022-1336

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology , Physics

Notes: A series of new crosslinked copolymers was obtained by cationic ring-opening copolymerization of 1,3,5,7-tetramethylcyclotetrasiloxane and 1,3,5-trioxane. The poly[(methylsiloxane)-co-(oxymethylene)] copolymers are white crystals or glassy. Crosslinking reactions take place in the reaction medium. The degree of crosslinking increases with a higher concentration of the methylsiloxane units in the copolymers. The combination of solid-state magic-angle spinning nuclear magnetic resonance of 29Si and 13C and Fourier-transform infrared spectroscopy provided a quantitative description of the copolymer microstructure.

Additional Material: 4 Ill.