| 학회 | 한국고분자학회 |
| 학술대회 | 2004년 가을 (10/08 ~ 10/09, 경북대학교) |
| 권호 | 29권 2호, p.88 |
| 발표분야 | 신규고분자 합성 |
| 제목 | Cationic Polymerization of Oxiranes for Energetic Prepolymer |
| 초록 | We synthesized energetic prepolymer(2-nitrato ethyl oxirane, NEO) and prepolymer(glycidyl dinitropropyl formal, GDNPF) for plastic-bonded explosive and measured its thermodynamic parameters. 2-nitrato ethyl oxirane(NEO) as a monomer was synthesized from 4-butene-ol, the first-step was preparation of 1-nitrato-3-butene and second-step was synthesized 2-nitrato-ethyl oxirane from 1-nitrato-3-butene. Glycidyl dinitropropyl formal(GDNPF) as a monomer was epoxidated from allyl-2-2-dinitropropyl formal which is reacted with dinitropropyl alcohol and exess allyl alcohol, and then polymerized by cationic ring opening polymerization1,2. The unreacted monomer concentration through polymerization were measured by GC. The thermodynamic parameters have been obtained; the ceiling temperature(Tc) values of 1 mole monomer are 249.7 and 271.0K for poly(NEO) and poly(GDNPF) respectively. The mechanism of the cationic polymerization of oxygen heterocyclic compounds has been much discussed. Cyclic oxonium ion is often thought to be the propagating species in the polymerization of oxetane3. The similarities in the kinetics and thermodynamics of polymerizations of the two monomers suggest a commonality of cyclic oxonium ions and open chain oxycarbenium ions are in equilibrium for the propagating species. We synthesized energetic prepolymer(NEO), and prepolymer(GDNPF) by activated monomer(AM) method4. We varied feed rate of monomer, concentration of initiator and monomer to control molecular weight and polydispersity of prepolymer. 1H-NMR spectra of the prepolymer are consistent with a regular microstructure for exclusive ring opening at the C-O bond during polymerization. Number average molecular weight(Mn), polydispersity(PD), and glass transition temperature(Tg) of prepolymer(NEO) were 1,800∼2000, 1.05∼1.07, -45∼55oC and prepolymer(GDNPF) were 2,500∼3,500, 1.30∼1,50, and -25∼30oC respectively. Fig. 1. 1H-NMR for prepolymer(NEO) Fig. 2. 1H-NMR for prepolymer(GDNPF) 참고문헌 1. J.C.W. Chien, Y.G. Cheun, and C.P. Lillya, Macromolecules, 21,870(1988) 2.Y.G. Cheun, J.K. Kim, Y.H. Kwon, and J.S. Kim, Polymer(Korea), 17, 2, 233(1993). 3.Y.G. Cheun, J.S. Kim, Synthesis and Charaterization energetic polymer(NMMO), polyer(GDPC) thermoplastic elastomer, report TEDC-419-0020151(2002) 4.Y.G. Cheun, J.S. Kim, Synthesis of energetic prepolymer(NEO), report TEDC-419-030540(2003) |
| 저자 | 전용구 |
| 소속 | 국방과학(연) |
| 키워드 | Prepolymer(NEO); prepolymer(GDNPF); activated monomer method(AM); ring open polymerization; ceiling temperature |
