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1.
2.
Monomer-isomerization polymerization of propenycyclohexane (PCH) with TiCl3 and R3-xAICIx (R = C2H5 or i-C4H9, x = 1–3) catalysts was studied. It was found that PCH underwent monomer-isomerization polymerization to give a high molecular weight polymer consisting of an allylcyclohexane (ACH) repeat unit. Among the alkyaluminum cocatalysts examined, (C2H5)3Al was the most effective cocatalyst for the monomer-isomerization polymerization of PCH, and a maximum for the polymerization was observed at a molar ratio of Al/Ti of about 2.0. The addition of isomerization catalysts such as nickel acetylacetonate [Ni(acac)2] to the TiCl3–(C2H5)3Al catalyst accelerated the monomer-isomerization polymerization of PCH and gave a maximum for the polymerization at a Ni/Ti molar ratio of 0.5. PCH also undergoes monomer-isomerization copolymerization with 2-butene (2B).  相似文献   

3.
Monomer-isomerization polymerization of cis-2-butene (c2B) with Ziegler–Natta catalysts was studied to find a highly active catalyst. Among the transition metals [TiCl3, TiCl4, VCl3, VOCl3, and V (acac)3] and alkylauminums used, TiCl3? R3Al (R = C2H5 and i-C4H9) was found to show a high-activity for monomer-isomerization polymerization of c2B. The polymer yield was low with TiCl4? (C2H5)3Al catalyst. However, when NiCl2 was added to this catalyst, the polymer yield increased. With TiCl3? (C2H5)3Al catalyst, the effect of the Al/Ti molar ratio was observed and a maximum for the polymer yields was obtained at molar ratios of 2.0–3.0, but the isomerization increased as a function of Al/Ti molar ratio. The valence state of titanium on active sites for isomerization and polymerization is discussed.  相似文献   

4.
The polymerizations of 4-methyl-1-pentene(4M1P), 4-methyl-2-pentene (4M2P), 2-methyl-2-pentene (2M2P), and 2-methyl-1-pentene (2M1P) with Ziegler-Natta catalyst have been investigated. Both 4M1P and 4M2P were found to polymerize with TiCl3–(C2H5)Al catalyst to give high molecular weight poly(4M1P), while 2M2P and 2M1P did not give polymers with 4M1P units. However, when the polymerizations of 2M1P and 2M2P were carried out with ternary catalyst systems, TiCl3–(C2H5)AlCl–(PPh3)2PdCl2 and TiCl3–(C2H5)AlCl–Ni(SCN)2 polymers with 4M1P units were obtained in low yield. It was concluded that these four methylpentenes could polymerize with the monomer-isomerization polymerization mechanism to poly(4M1P). The results of the observed isomer distribution of methylpentenes recovered, and the rate of polymerization of four methylpentenes suggest that the isomerization from 2M1P to 4M1P with the above ternary catalyst systems might proceed via a direct one-step isomerization mechanism.  相似文献   

5.
1,4-Cyclohexadiene underwent monomer-isomerization polymerization to yield poly(1,3-cyclohexadiene) with a Ziegler-Natta catalyst comprising TiCl4–Al(C2H5)3 catalyst with Al/Ti molar ratios of 0.5–3.0 at 60°C for 96 hr. Good yields of polymer were obtained (49.5% yield at Al/Ti = 3.0; [η] = 0.04 dl/g). The infrared and NMR spectra of the polymer were identical to those of poly-(1,3-cyclohexadiene), confirming that 1,4-cyclohexadiene first isomerizes to 1,3-cyclohexadiene and then homopolymerizes to give poly-1,3-cyclohexadiene. 1,3-Cyclohexadiene polymerized without isomerization easily in the presence of TiCl3–Al(C2H5)3 catalyst at Al/Ti molar ratios of 0.5–3.0 at 60°C for 3 hr (76.3% yield at Al/Ti = 3.0; [η] = 0.06 dl/g).  相似文献   

6.
5-Phenyl-2-pentene (5Ph2P) was found to undergo monomer-isomerization polymerization with TiCl3–R3Al (R = C2H5 or i-C4H9, Al/Ti > 2) catalysts to give a polymer consisting of exclusively 5-phenyl-1-pentene (5Ph1P) unit. The geometric and positional isomerizations of 5Ph2P to its terminal and other internal isomers were observed to occur during polymerization. The catalyst activity of alkylaluminum examined to TiCl3 was in the following order: (C2H5)3Al > (i-C4H9)3Al > (C2H5)2AlCl. The rate of monomer-isomerization polymerization of 5Ph2P with TiCl3–(C2H5)3Al catalyst was influenced by both the Al/Ti molar ratio and the addition of nickel acetylacetonate [Ni(acac)2], and the maximum rate was observed at Al/Ti = 2.0 and Ni/Ti = 0.4 in molar ratios.  相似文献   

7.
The copolymerization of 3-methyl-1-butene (3M1B), 2-methyl-2-butene (2M2B), or 2-methyl-1-butene (2M1B) with trans-2-butene (2B) was attempted in the presence of a Ziegler-Natta catalyst. It was found the 3M1B underwent monomer-isomerization copolymerization with 2B to give a copolymer consisting of both 3M1B and 1-butene (1B) units, with an infrared (IR) spectrum in good agreement with that obtained from the copolymerization of 3M1B with 1B under similar conditions. When the apparent copolymerization parameters obtained by a TiCl3–(C2H5)3Al catalyst were compared, the apparent reactivity of 3M1B observed in the 3M1B-2B system was much higher than that in the 3M1B-1B system. However, 2M2B and 2M1B did not undergo monomer-isomerization copolymerization with 2B, and only the homopolymer of 1B was obtained under similar conditions.  相似文献   

8.
Monomer-isomerization copolymerizations of styrene (St) and cis-2-butene (c2B) with TiCl3-(C2H5)3Al catalyst were studied. St and c2B were found to undergo a new type of monomer-isomerization copolymerization, i.e., only isomerization of 2B to 1-butene ( 1B ) took place to give a copolymer consisting of St and 1B units. The apparent copolymerization parameters were determined to be rst = 16.0 and rc2b = 0.003. The parameters were changed by the addition of NiCl2 (rSt = 8.4, rc2b = 0.05). The copolymers containing the major amount of St units were produced easily through monomer-isomerization copolymerization of St and 2B. © 1995 John Wiley & Sons, Inc.  相似文献   

9.
A study of the monomer isomerization polymerization of 2-, 3-, and 4-octenes has been made with TiCl3–(C2H5)3Al catalyst at 80°C in comparison with the ordinary polymerization of 1-octene. It was found that all these octenes underwent monomer-isomerization polymerization to give high-molecular-weight homopolymer consisting exclusively of the 1-octene unit. The addition of an isomerization catalyst such as nickel acetylacetonate accelerated this polymerization. The rates of polymerization were found to decrease in the following order: 1-octene > 2-octene > 3-octene > 4-octene. These results indicate that the isomerization proceeded by a stepwise double-bond migration. It was also found that the monomer-isomerization copolymerization of 2-octene and 2-butene occurred under similar conditions and produced copolymers of both 1-olefin units.  相似文献   

10.
Summary The synthesis of three vinylbenzyl complexes (n5-C5H5)-M(CO)n(CH2C6H4CH=CH2), [1), M=Mo, n=3; (2), M=W, n=3; (3), M=Fe, n=2] is reported. Complexes (1) and (2) have been copolymerized with monomers, such as styrene, methyl methacrylate, andN-vinyl-2-pyrrolidone, in benzene using azoisobutyronitrile as initiator. The rates of incorporation of (2) into copolymers with styrene and methyl methacrylate were the same as the rate of incorporation of the organic monomer. The homopolymerization of (2) was also carried out. Polymerizations occurred satisfactorily except for the copolymerization of (1) with styrene, where little incorporation of the organometallic monomer occurred.  相似文献   

11.
2-Pentene and 2-hexene were found to undergo monomer-isomerization copolymerizations with 2-butene by Al(C2H5)3–VCl3 and Al(C2H5)3–TiCl3 catalysts in the presence of nickel dimethylglyoxime or transition metal acetylacetonates to yield copolymers consisting of the respective 1-olefin units. For comparison, the copolymerizations of 1-pentene with 1-butene and 1-hexene with 1-butene by Al(C2H5)3–VCl3 catalyst were also attempted. The compositions of the copolymers obtained from these copolymerizations were determined by using the calibration curves between the compositions of the respective homopolymer mixtures and the values of D766/D1380 in the infrared spectra. The monomer reactivity ratios for the monomer-isomerization copolymerizations of 2-butene (M1) with 2-pentene and 2-hexene, in which the concentrations of both 1-olefins calculated from the observed isomer distribution were used as those in the monomer feed mixture, and for the ordinary copolymerizations of 1-butene (M1) with 1-pentene and 1-hexene by Al(C2H5)3-VCl3 catalyst were determined as follows: 2-butene (M1)/2-pentene (M2): r1 = 0.14, r2 = 0.99; 1-butene (M1)/1-pentene (M2): r1 = 0.30, r2 = 0.74; 2-butene (M1)/2-hexene (M2): r1 = 0.11, r2 = 0.62; 1-butene (M1)/1-hexene (M2): r1 = 0.13, r2 = 0.90.  相似文献   

12.
A study of the isomerization of butene-2 with TiCl3 or Al(C2H5)3–TiCl3 catalyst in n-heptane has been investigated at 60–80°C to elucidate further the mechanism of monomer-isomerization polymerization. It was found that positional and geometrical isomerizations in the presence of these catalysts occurred concurrently with activation energies of 14–16 kcal/mole. The presence of Al(C2H5)3 with TiCl3 catalyst could accelerate the initial rates of these isomerizations and initiate the monomer-isomerization polymerization of butene-2. From the results obtained, it was concluded that the isomerization of butene-2 proceeds via an intermediate σ-complex between the transition metal hydride and butene isomers.  相似文献   

13.
Photopolymerization of a mixture of cyclohexene oxide and nitroethylene was carried out with the purpose of carrying out cationic and anionic polymerizations simultaneously in the same system. The excitation of the charge transfer band by light of wavelength longer than 390 nm gives rise to the polymerization of both monomers. No polymer was obtained in the dark. Additives affect the composition of the polymer, the rates of polymerization, and the molecular weight distributions. These data show that cationic polymerization of cyclohexene oxide and anionic polymerization of nitroethylene occurs simultaneously in this system.  相似文献   

14.
15.
4-Phenyl-2-butene (4Ph2B) undergoes monomer-isomerization copolymerization with 4-methyl-2-pentene (4M2P) and 2-and 3-heptene (2H and 3H) with TiCl3–(C2H5)3Al catalyst at 80°C to produce copolymer consisting exclusively of 1-olefin units. For comparison the copolymerization of 4-phenyl-1-butene (4Ph1B) with 4-methyl-1-pentene (4M1P) and 1-heptene (1H) was carried out under similar conditions. The composition of the copolymers obtained from these copolymerizations was determined from the ratios of optical densities D1380 and D1600 of infrared (IR) spectra of their thin films. The apparent monomer reactivity ratios for the monomer-isomerization copolymerization of 4Ph2B with 4M2P, 2H, and 3H in which the concentration of olefin monomer in the feed was used as internal olefin and those for the copolymerization of 4Ph1B with 4M1P and 1H were determined as follows: 4Ph2B(M1)-4M2P(M2); r1 = 0.90, r2 = 0.20, 4Ph1B(M1)-4M1P (M2); r1 = 0.40, r2 = 0.70, 4Ph2B(M1)-2H(M2); r1, = 0.45, r2 = 1.85, 4Ph2B(M1)-3H(M2); r1 = 0.50, r2 = 1.20, 4Ph1B(M1)-1H(M2); r1 = 0.55, r2 = 0.75. The difference in monomer reactivity ratios seemed to originate from the rate of isomerization from 2- or 3-olefins to 1-oletins in these monomer-isomerization copolymerizations.  相似文献   

16.
2-Phthalimidomethyl 1,3-butadiene was homopolymerized and copolymerized with butadiene by free radical initiators; r1 and r2 were close to 1. All the attempts to polymerize 2PMB anionically have been unsuccessful. Preliminary studies of various η3-allylic catalysts showed that η3-allyl M0(CO)3OOCCF3 initiates the polymerization of butadiene and is not sensitive to N-methyl phthalimide (NMP); neither does it initiate the copolymerization of butadiene and 2PMB. On the other hand, a catalyst that results from the reaction of allyl trifluoroacetate with nickel tetracarbonyl is efficient for the copolymerization of butadiene and 2PMB. η3-Allyl nickel trifluoroacetate was prepared in heptane or benzene and used in benzene or methylene chloride. In all cases it initiated the copolymerization of butadiene with 2PMB  相似文献   

17.
The thermal decomposition of butene-2-cis at low conversion and its effect on the pyrolysis of propane have been studied in the temperature range 779-812 K. It was established that 2-butene decomposes in a long-chain process, with the chain cycle (Besides the radical path, the molecular reaction can also play a role in the formation of the products.) The thermal decomposition of propane is considerably inhibited by 2-butene, which can be explained by the fact that the less reactive radicals formed in the reactions between the olefin and the chain-carrying radicals regenerate the chain cycle more slowly than the original radicals in the above chain cycle or in the reactions The reactions of the 2-propyl radical are further initiation steps. The ratios of the rate coefficients of the elementary steps of the decomposition (Table III) have been determined via the ratios of the products. Estimation of the radical concentrations indicated that only the methyl, 2-propyl and methylallyl radicals are of importance in the chain termination. On the basis of the inhibition-influenced curves, the role of the bimolecular initiation steps. could be clarified in the presence of 2-butene.  相似文献   

18.
3-Methyl-1-butene (3M1B) was found to undergo monomer-isomerization copolymerization with 2-pentene (2P) in the presence of Ziegler–Natta catalyst to give a copolymer exclusively consisting of 3M1B and 1-pentene (1P) units, the same as that obtained from copolymerization of 3M1B and 1P. The apparent copolymerization parameters were determined. The amount of 3M1B unit incorporated in the copolymers was found to increase in the copolymerization system of 3M1B-2P more than in that of 3M1B-1P. The polymers consisting of nearly complete 3M1B units were produced at a rapid rate through monomer-isomerization copolymerization of 3M1B with 2P in the presence of TiCl3 ? (C2H5)3Al catalyst.  相似文献   

19.
Monomer-isomerization polymerization of cis-2-butene with four types of TiCl3 in combination with alkylaluminum compounds was investigated. The catalytic activities for monomer-isomerization polymerization were found to be influenced by the type of TiCl3 employed: systems containing hydrogen-activated-TiCl3 and Solvay-TiCl3 in combination with R3Al (R = C2H5 and i-C4H9) showed high catalytic activity for both isomerization and polymerization, whereas (C2H5)2AlCl in combination with any type of TiCl3 did not induce the monomer-isomerization polymerization. The addition effect of NiCl2 to the TiCl3? (C2H5)3Al catalyst was examined. Catalytic activities for both polymerization and isomerization reactions were found to depend on the amount of NiCl2 added.  相似文献   

20.
The isomerization and polymerization of propenylbenzene (PB) with various Ziegler–Natta catalyst systems have been investigated. With the TiCl3–(C2H5)3Al (Al/Ti > 2.0) catalyst at 80°C, PB polymerized to give a polymer exclusively consisting of allylbenzene (AB) unit. During the polymerization, AB, which polymerized readily with the catalyst, was produced through isomerization of PB, indicating that PB underwent monomer-isomerization polymerization. PB also polymerized with isomerization to AB in the presence of TiCl3?(C2H5)2AlCl?NiCl2 catalyst system, and a copolymer with PB and AB units was obtained. With TiCl3?C2H5AlCl2 catalyst, poly(PB) was formed via ordinary vinylene polymerization without isomerization. From these facts, it was concluded that the structure of the polymers produced from PB widely changed, depending on the catalyst systems used, which determine the rate of isomerization to AB and the polymerization reactivity of the PB and AB isomers formed.  相似文献   

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