Syndiotactic Polymer of Allylcyclopentane by a Metallocene Catalyst

Abstract

Syndiospecific (co)polymerization of some higher α‐olefins was performed by using a metallocene catalyst. Homopolymers of allylcyclopentane, 4‐methyl‐1‐pentene, and allylcyclohexane are highly syndiotactic. The results of the copolymerization of allylcyclopentane with 1‐hexene, 1‐octene, or 1‐decene showed that the incorporation of a linear higher α‐olefin interfered with the syndiospecificity of the catalyst, and the melting point of the resulting copolymer decreased with the incorporation of the comonomer. In contrast, the copolymer of allylcyclopentane with 4‐methyl‐1‐pentene or allylcyclohexane maintained the high syndiotacticity, and the melting point also remained almost unchanged no matter how much the comonomer was incorporated. It followed that the “shape” of the monomer had a significant influence on the structure of the copolymer. The monomers employed in copolymerization with a similar “shape” gave a copolymer with a similar microstructure.

Integrated Effect of Comonomer and Catalyst on Copolymerization of Ethylene with Allylcyclopentane or Allylcyclohexane by Using Metallocene Catalysts

“…[f] (mol %) . [26] The 13 C-NMR spectrum of the copolymer of ethylene with ACH (run 9) was shown in Figure 2 (b). By using the similar tack, the spectrum could be assigned and the assignments tally with the previous work.…”

“…By using the similar tack, the spectrum could be assigned and the assignments tally with the previous work. [26] The assignments of the copolymers of ethylene with ACP or ACH were shown in Table 2. Table 3 showed the comonomer sequence distributions.…”

“…We concluded that the structure of the comonomer strongly influenced the polymerization activity and the microstructure of the resulted polymer. [14,[24][25][26] In the copolymerization of ethylene with α,ω-alkenols, the length of the alkenol monomer strongly impacts on the microstructure of the copolymer. Alkenol with fewer methylene spacers trends to give the copolymer with more successive comonomer segments, at the same time, the structure of the copolymer obtained from the alkenol with the more methylene spacers is more random.…”

“…[14,24] Especially, we realized that the length and the structure of the comonomer give an important impact on the melting point and the stereoregularity of the polymer. [25,26] Thus, we will explore more novel comonomers for copolymerization, intending to get new polymer with new chemical composition, and enrich the investigation of the comonomer effect.…”

“…[30][31][32][33][34] We have reported the 1,2-insertion of ACP and ACH by a metallocene catalyst (see Figure 1). [26] In this manuscript, we will introduce the results of the copolymerization of ethylene with ACP or ACH by using metallocene catalysts (see Scheme 1).…”