ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Linear ABA triblock and (AB)n segmented block copolymers of energetic monomers have been synthesized. The rigid and soft blocks are prepared from 3,3-bis(azidomethyl)oxetane (BAMO) and 3-nitratomethyl-3-methyloxetane (NMMO), respectively. Polymerization of BAMO initiated by triethyloxonium tetrafluoroborate and by spiro(benzoxasilole)/propanediol produced α,ω-monohydroxy-PBAMO (3) and α,ω-dihydroxy-PBAMO (4) of M̄n 16,000 and 2,000, respectively, and α,ω-dihydroxy-PNMMO (5) of M̄n = 13,000 was synthesized by the latter method. The block copolymers were prepared from the appropriate telechelic polymers and toluene diisocyanate. The PBAMO - PNMMO - PBAMO copolymer 6 has Tm = 82°C, Tg = -3°C, and is strongly phase separated even in the melt. It decomposes sharply within 1°C at 224°C evolving 0.69 kJ/g of heat. Copolymer 6 has excellent mechanical properties with elongation of 683% at break, 5.25 MPa stress, and 82% recovery. The (PBAMO - PNMMO)n copolymer 7 has similar thermal properties and spectroscopic characteristic, but is inferior to copolymer 6 in all rheological and mechanical properties. © 1992 John Wiley & Sons, Inc.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1992.070460908
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