Poly(norbornene-co-styrene)s were synthesized by the use of anilinonaphthoquinone-ligated nickel complexes [Ni(C10H5O2NAr)(Ph)(PPh3): 1a, Ar = C6H3-2,6-iPr; 1b, Ar = C6H2-2,4,6-Me; 1c, Ar = C6H5] activated with modified methylaluminoxane (MMAO) or B(C6F5)3 in toluene. The effects of the cocatalysts were more significant than those of the nickel complexes, and MMAO gave higher activity than B(C6F5)3. The structural characterizations of the products indicated the formation of statistical norbornene copolymers. An increase of the styrene ratio in feed led to an increase in the incorporated styrene (S) content of the resulting copolymer. The molecular weight of the copolymer decreased with increasing the S ratio in feed at 70 °C. The copolymerization activity, using MMAO as a cocatalyst, decreased with lowering of the temperature from 70 to 0 °C, accompanied by an increase in the molecular weight of the copolymer. The S incorporation up to 59% with Mn of 78,000 was achieved by the 1b-B(C6F5)3 catalytic system. The glass transition temperatures of the norbornene (N)/S copolymers determined by differential scanning calorimetry, decreased from 329 to 128 °C according to the S content.

Coordination‐insertion copolymerization of norbornene (N) and p‐substituted styrene (XS) (X = MeO, Me F, Cl, and Br) is carried out using anilinonaphthoquinone‐ligated nickel complexes [Ni(C10H5O2NAr)(Ph)(PPh3): 1a, Ar = C6H3‐2,6‐iPr; 1b, Ar = C6H2‐2,4,6‐Me; 1c, Ar = C6H5] with modified methylaluminoxane (MMAO) as a cocatalyst. The ligand of the nickel complex affects the catalytic activity. The effect of the p‐substituent on the activity is remarkable and the activity decreases in the following order, Br > Cl > F > Me > MeO. The molecular weight of the produced polymer also decreases with the same order. The activity increases with raising the temperature from 0 to 70 °C accompanied by the decrease in the molecular weight of the produced polymers. The incorporation of XS determined by 1H and 13C NMR decreases in the following order, MeO ≥ Me > F > Cl > Br. The glass transition temperatures of the N/XS copolymers determined by differential scanning calorimetry show a broad range from 120 to 365 °C according to the XS content.

No abstract

The copolymerization of norbornene (NB) and divinylbenzene (DVB) was carried out using anilinonaphthoquinone-ligated nickel complexes of the type [Ni (C 10 H 5 O 2 NAr)(Ph)(PPh 3 )] (1a: Ar = C 6 H 3 -2,6-i Pr; 1b: Ar = C 6 H 2 -2,4,6-Me; 1c: Ar = C 6 H 5 ) with modified methylaluminoxane (MMAO) as a cocatalyst. The DVB content was varied (5-25 mol%) and the resulting copolymers exhibited number-average molecular weights (M n ) of 40,000-69,000 g/mol with polydispersities (PDI = 1.5-1.8). The styryl group of the NB/DVB copolymer was used for grafting poly(methyl methacrylate) by reverse atom transfer radical polymerization using azobisisobutyronitrile in the presence of copper chloride and bipyridine.

Atom Transfer Radical Polymerization (ATRP) has proven to be a powerful technique to obtain polymers with narrow polydispersities and controlled molecular weight. It also offers control over chain-ends. N-allyl-2-bromopropinamide (ABPN) was synthesized by one step reaction which involved on amidification of 2-bromo-propionyl bromide with allyl amine. 1 H NMR has confirmed the structure of the ABPN. The well-defined polystyrene was synthesized by using ABPN as initiator in ATRP method. The results of the polymerization were significantly affected by reaction conditions. The vinyl end-functional polystyrene obtained was characterized by Gel Permeation Chromatography (GPC) and NMR analysis.