• Polymer(Korea)
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• v.28 no.3
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• pp.245-252
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• 2004

We synthesized the vinyl addition-type polynorbomene copolymers using two monomers [5-hexyl-2-norbornene (HNB) and 5-methyleste-2-norbornene(MES-NB)] by means of a cationic ${\eta}^3$-allyl palladium catalyst system{[(${\eta}^3$-allyl)palladium(tricyclohexylphosphine) trifluoroacetate] and [lithium tetrakis(pentafluorophenyl) borate ${\cdot}$2.5 etherate]}. The molecular weights and yields of copolynorbomenes polymerized in various conditions were measured to investigate an optimum polymerization conditions to obtain highly ester-functionalized polynorbomenes. As a Pd catalyst content increased, the molecular weights (Mw) of polymers decreased while polymer yields increased. Also, as a Li cocatalyst content increased, the Mw’s and yields of polymers increased at the same time. The Mw’s of copolymers were also controlled by chain transfer agents such as 1-hexone, 1-octene and 1-decene, and we found that longer 1-decene and 1-octene were more efficient to reduce the Mw’s of polynorbornenes than 1-hexene. On the other hand, the content of chain transfer agents did not give influence significantly on polymer yields. From the $^1$H-NMR and GPC analysis of HNB/MES-NB(feed ratio of 40/60 mol%) copolymer, we found that this copolymer had an about 25 mol% of ester portion and a high molecular weight of 270,000.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.2 s.21
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• pp.67-76
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• 2005

We synthesized an energetic prepolymer(glycidyl dinitro propyl formal, GDNPF) for plastic-bonded explosive and measured its thermodynamic parameters. Glycidyl dinitro propyl formal(GDNPF) as an energetic monomer was epoxidized from allyl-2,2-dinitro propyl formal which is reacted with dinitro propyl alcohol and excess allyl alcohol, and then energetic polymer of GDNPF was polymerized by cationic ring opening polymerization. Thermodynamic parameters were obtained from the ceiling temperature($T_c$) values of 1 mole monomer at reaction temperature. We varied feed rate of monomer, concentration of initiator and monomer to control molecular weight and polydispersity of prepolymer (GDNPF). The activated monomer polymerization has been executed with precisely controlled feed of GDNPF monomer to reactor in the complex state catalyst generated by $BF_3{\cdot}(C_3H_5)_2$ and 1,4-butanediol in $C_2H_4Cl_2$. Number average molecular weight(Mn), polydispersity(Pd), hydroxy number and glass transition temperature($T_g$) of prepolymer(GDNPF) were $2,500{\sim}3,000,\;1.2{\sim}1,3,\;0.6{\sim}0.8eq/kg\;and\;-20{\sim}-25^{\circ}C$ respectively.