Studies on the charge transfer complex and polymerization. XIV. Spontaneous copolymerization of 1-methylcyclopropene and sulfur dioxide

Copolymerization between 1-methylcyclopropene (MCP) and sulfur dioxide (SO₂) was studied. It took place spontaneously even at a low temperature, and was found to be consistent with polymerization by a “living” radical, as suggested by the increase of reduced viscosity with conversion and by the formation of block polymers in the presence of acrylates. The rate of copolymerization was proportional to [MCP]³ and [SO₂]², and the overall activation energy of copolymerization was about 15.1 kcal/mole. A tentative mechanism to explain the experimental results is discussed.     

Vinyl Polymerization Initiated by Sulfur Dioxide

Abstract

A number of monomers have been polymerized in the presence of catalytic and higher concentrations of SO₂. The addition of t-butyl hydroperoxide greatly accelerates the rate of polymerization. The use of ³⁵SO₂ indicates that at catalytic concentrations of SO₂ (10^?2 mole/liter), only one or two molecules of SO₂ are incorporated in the chain, but, at high SO₂ concentrations, copolymerization of SO₂ with vinyl monomers occurs.     

Free radical copolymerization of sulfur dioxide with 1-alkynes

Free radical copolymerization of SO₂ with 1-alkynes (AY) was studied by evaluation of the copolymerization rate under controlled conditions of copolymerization temperature and monomer concentration product ([AY][SO₂]). The poly(alkyne sulfone)s always contained equimolar units of SO₂ and alkyne, regardless of the copolymerization conditions. Using 1-hexyne (HY) and 1-octyne (OY) as comonomers of SO₂, the values of ceiling temperature (T_c) were determined: when [HY][SO₂] = [OY][SO₂] = 0.25 mol²/L², the values of T_c were 90.5 and 84.5°C, respectively. T_c increases with increasing monomer concentration product. The activation energies for propagation (E_p) and depropagation (E_d) of the SO₂-alkynes copolymerization system were investigated, using the SO₂? OY copolymerization system, and estimated to be 12.2 and 26.7 kcal/mol, respectively. The value of E_d is high compared with that of the copolymerization of SO₂ and 1-butene (20.3 kcal/mol), demonstrating that the free radical endings (～ OY? SO₂ and ～ SO₂? OY) are difficult to depropagate, compared with those formed from the copolymerizaton of SO₂ and 1-butene. ΔS and ΔH_p, calculated from experiments, were found to be ?37.7 cal/mol K and ?14.3 kcal/mol, respectively     

Vinyl polymerization by cobaltic ions in aqueous solution. Part II. Polymerization of acrylonitrile and methyl acrylate

Polymerization of methyl acrylate in HClO₄ and HNO₃ was studied in the temperature range 10–15°C. The kinetics of the polymerization were found to be very simple, involving initiation and termination by cobaltic ions. Kinetic studies on polymerization of acrylonitrile in HClO₄ and HNO₃ revealed that water oxidation, and monomer oxidation were side reactions as in the case of methyl methacrylate. Experimental evidence favored the simultaneous initiation by Co³⁺ and CoOH²⁺ species. In H₂SO₄, certain unusual features were encountered. At low [Co³⁺], linear termination as well as termination by mutual combination occurred. Another interesting aspect was that CoSO₄⁺ initiated at low [Co³⁺]. This was unlike the case of other monomers in H₂SO₄. The rates of polymerization and rates of cobaltic ion disappearance were measured with respect to changes in [M], [Co³⁺], [H⁺], temperature, etc. The various rate constants were evaluated.     

Propagation Mechanism of Radical Copolymerization of Sulfur Dioxide and Vinyl Chloride

Radical copolymerization of sulfur dioxide and vinyl chloride (VC) has been studied by the comparison of the composition of copolymers obtaining from different reaction conditions, i.e., reaction temperatures, feed compositions, and total monomer concentrations. The composition of VC in copolymer is independent of comonomer composition except at high concentration of VC in feed; it increases with increasing reaction temperature or decreasing total monomer concentration. At lower temperature, the composition of copolymer becomes independent of total monomer concentration. The overall rate of polymerization is proportional to [VC]^1,7 and [SO₂]^0.5. These results were compared with those obtained in our previous study on the SO₂-styrene copolymerization. A propagation mechanism for radical copolymerization of SO₂ and VC is also proposed.     

Alternating copolymerization of ethylene oxide and sulfur dioxide

Copolymerization of ethylene oxide (EO) and sulfur dioxide (SO₂) was conducted by using a variety of amines as catalyst. Aromatic tertiary amines such as quinoline and pyridine were found to show the best catalytic property of the various amines, and copolymerization was carried out in the temperature range between 0 and 80°C with the use of quinoline. The copolymerization rate was approximately first-order in quinoline, EO, and also SO₂. The copolymer, was always composed of the two monomers: 1:1 ratio, independent of the initial concentration of the monomers. The copolymer obtained was a transparent viscous material which decomposed at 218°C to afford a considerable amount of ethylene sulfite. Spectroscopic analysis of the copolymer combined with the results of elemental analysis indicates the copolymer to have the structure The polymerizability of ethylene sulfite, which might be considered an intermediate compound in the copolymerization, was also examined at 60°C for 4 hr in the presence of quinoline, and it was found that ethylene sulfite could not be polymerized under these conditions.     

COPOLYMERIZATION OF 1-OCTENE WITH STYRENE BY RARE EARTH COORDINATION CATALYSTS

The copolymerization of l-octene with styrene catalyzed by rare earth coordination catalysts has been studied for the first time. Some features and kinetic behavior are described. The overall activation energy of the copolymerization was 22.2 KJ/mol and the copolymerization rate could be expressed as R_p=K_p [Nd] [M]~2. (=1.68×10~(-3) L~2/mol~2. S, 50℃, [Oct]/[St]=1). The catalytic activity of various rare earth elements in Ln (naph)_3 for the copolymerization was compared and shows the following sequence: Dy, Y, Yb>Ho>Sm, Gd, Nd>Pr>Ce>La>Tm. Both monomers of l-octene and styrene in the copolymerization by Nd (naph)_3-AlEt_3 have the tendency of constant proportion copolymerization. The structure of the copolymers was studied by ~1H-NMR.     

Effect of substituents on addition polymerization of norbornene derivatives with two Me3Si-groups using Ni(II)/MAO catalyst

Addition polymerization and copolymerization of bis(Me₃Si)-substituted norbornene-type monomers such as 5,5-bis(trimethylsilyl)norbornene-2, 2,3-bis(trimethylsilyl)norbornadiene-2,5 and 3,4-bis(trimethylsilyl)tricyclo[4.2.1.0^2,5]nonene-7, in the presence of Ni(II) naphtenate/MAO catalyst were studied. Disubstituted norbornene and norbornadiene were found to be practically inactive in homopolymerization. On the other hand, their copolymerization with norbornene proceeded with moderate yields of copolymers containing predominantly norbornene units. Under studied reaction conditions 2,3-bis(trimethylsilyl)norbornadiene-2,5 was transformed into the only exo-trans-exo-dimer as a result of the [2+2]-cyclodimerization reaction. Moving Me₃Si-substituents one carbon atom away from norbornene double bond made 3,4-bis(trimethylsilyl)tricyclo[4.2.1.0^2,5]nonene-7 active in homopolymerization and allowed to obtain addition homo-polymer with two Me₃Si-substituents in each elementary unit. The reaction mechanism and steric effect of Me₃Si-substituents are also discussed.     

Functional monomers and polymers. XXXXVI. A copolymerization study of methacryloyl-type monomers containing nucleic acid bases in chloroform solution

Behavior of the free radical copolymerization of N-β-methacryloyloxyethyl derivatives of adenine with that of thymine was studied in chloroform solution, taking account of the specific base-base interaction of these monomers. Hydrogen bonding interaction between such monomers was observed by NMR spectroscopy. The acceleration of copolymerization was found to be greater either at lower monomer concentration or at lower polymerization temperature. When N-β-methacryloyloxyethylcarbazole was used as a comonomer, the rate of copolymerization showed a similar trend as in the case of usual free radical copolymerizations. From r₁ and r₂ values obtained, the copolymerization was found to be alternating, particularly in the case of copolymerization between monomers having complementary nucleic acid bases. The results suggest that the hydrogen bonding interaction between adenine and thymine plays a role in the propagation step.     

Emulsion copolymerization of tetrafluoroethylene and propylene with redox system containing tert-butylperbenzoate. I. Polymerization conditions and components

Emulsion polymerization of tetrafluoroethylene and propylene with ammonium perfluorooctanoate, initiated by a redox system containing tert-butylperbenzoate (TBPB) was carried out. The effect of the components of the redox system Is (TBPB, FeSO₄.7H₂O, ethylenediamine tetraacetic acid (EDTA), and CH₂(OH)SO₂Na.2H₂O) on the polymerization rate (R) and molecular weight () was studied. Among redox system components, Fe²⁺ concentration exerts the most significant effect (by power of 0.54) on the polymerization rate. It was found that R ∝ [Is]^0.2–0.54 and M_n ∝ [Is]^0.0–0.1 and polymerization reaction scheme was suggested for the action of the initiating system. The influence of the copolymerization conditions (pressure, temperature, stirring speed, and pH) is also discussed. The apparent activation energy of the reaction was found to be 46.0 kJ/mol. © 1994 John Wiley & Sons, Inc.     

Well phase separated segmented copolymers via acyclic diene metathesis (ADMET) polymerization

Segmented oligomers consisting of polyoctenylene hard segments and unsaturated polytetrahydrofuran soft segments were prepared using acyclic diene metathesis (ADMET) copolymerization techniques. These are the first such segmented materials prepared via metathesis chemistry. Two different molecular weight α,ω-poly(tetrahydrofuran)diene soft segment monomers of the structure [CH₂CH(CH₂)₄[O(CH₂)₄]-_nO(CH₂)₄CHCH₂] (1) were synthesized by the cationic living polymerization of tetrahydrofuran (THF). Trifluoromethanesulfonic anhydride, (CF₃SO₂)₂O (triflic anhydride) (2), was employed as the initiator, followed by in situ bis-functionalization with 5-hexen-1-ol, [CH₂=CH(CH₂)₄OH] (3), to yield soft segment dienes with vinyl end groups. The functionality of these soft segment monomers was approximately 1.9. These telechelic monomers possessed sufficient functionality to be homopolymerized or copolymerized with 1,9-decadiene (4) to generate well phase separated, segmented oligomers exhibiting hard segment/soft segment thermal behavior. The segmented copolymers were characterized by ¹H-NMR, ¹³C-NMR, and IR spectroscopy, elemental analysis, and TGA and DSC analysis. Average molecular weights were determined by gel permeation chromatography (GPC) and end-group analysis. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3441–3449, 1997     

THE MECHANISM OF THE COPOLYMERIZATION OF BF_3-COMPLEXED ETHYL ACRYLATE WITH PROPYLENE

The copolymerization of BF_2-omplexed ethyl acrylate with propylene in the presence ofAIBN at 25℃was investigated. It was found that the rate of the copolymerization was propor-tional to the square root of the initiator concentration. The chain transfer agent CCl_4 greatly af-fects the inherent viscosity of the resulting copolymer. The smaller the dielectric constant of thesolvent, the greater the rate of copolymerization is. The equal concentration of the two monomersgive the maximum copolymerization rate. The ~1H-NMR and ~(13)C-NMR analysis indicated, when[EA.BF_2]/[EA.BF_2]+[P]>0.5, the resulting copolymer was the acrylate-rich random copoly-mer. Through the kinetic experiments we suggest that copolymerization follows the mechanismof the random copolymerization of the ternary complex with binary complex. When [EA.BF_3]/[EA.BF_2]+[P]<0.5, the resulting copolymer is always strictly alternating, and the alternatingcopolymerization follows the mechanism of the ternary complex homopolymerization. Usingthe homolog of the propylene, 1-pentene, we found that BF_3-complexed ethyl acrylate can forma ternary complex with 1-pentene identified by UV spectroscopy. This is a strong evidence forthe mechanism of ternary complex homopolymerizetion.     

Organoborazines. III. Homo- and copolymerization of p-vinylphenylcyclotriborazines

The polymerization and copolymerization with styrene of a series of unsymmetrically B-p-vinylphenyl-N-methyl and N-phenyl borazines [R³(R²)₂B₃N₃(R¹)₃; R¹ = methyl, phenyl, R² = methyl phenyl, R³ = p-vinylphenyl] has been studied. The polymerization of these monomers yielded both tractable and crosslinked materials. The polymers obtained were characterized by ¹H- and ¹³C-NMR spectroscopy, elemental analysis, gel permeation chromatography, and thermogravimeteric analysis. The reactivity ratios for the copolymerization reaction were calculated by the Mortimer-Tidwell method.     

二烷基锡聚合物的研究——Ⅲ.顺丁烯二酸二丁基锡酯与丙烯酸甲酯、丙烯酸丁酯的共聚合

Benzoyl peroxide (BPO) was used for initiator in copolymerization of dibutyltin maleate (DBTM, M₂) with methyl acrylate (MA, M₁) in benzene and the reactivity ratios of copolymerization r1 and r2 were found to be 12.67 and 0.03, respectively. But in copolymerization of DBTM (M₂) with butyl acrylate (BA, M₁) r1 and r2 were 11.1 and 0> respectively. The cc-polymerization conditions, such as amount of initiator, ratios of monomers and addition method of initiator were examined. Copolymers were characterized by ¹H-NMR,IR,elemental and TG analyses. MA-DBTM copolymer is a white and brittle solid, while BA-DBTM copolymer is a transparent elastomer at room temperature.     

Radical Copolymerization of Vinylidene Chloride with 3(2-Methyl)-6-methylpyridazinone in Several Solvents

The radical copolymerization of vinylidene chloride (Vc, M₁) with 3(2-methyl)-6-methylpyridazinone (I, M₂) was carried out in benzene, ethanol, phenol, and acetic acid at 60 and 80°C. The monomer reactivity ratios were found to vary with the reaction conditions. The linear correlationships were obtained by plotting the values of log r₁ against those of ^V C[dbnd]O and ^V C[dbnd]C of monomers determined in the solvents.     

Polymerization and Catalytic Properties of Cluster-Containing Monomers and Polymers

Summary : Cluster-containing monomers were obtained and characterized. Mono- and disubstituted products were obtained under mild conditions via the interaction of Rh₆(CO)₁₆ with 4-vinylpyridine (4-VPy). Substitution of labile acetonitrile ligand in Rh₆(CO)₁₅NCMe by allyldiphenylphosphine (AlPPh₂) yields Rh₆(CO)₁₄(µ,η²-PPh₂CH₂CHCH₂) with formation of π-complex. The copolymerization of cluster-containing monomers synthesized with traditional monomers has been studied. It was found that Rh₆- containing monomers change neither the ligand surroundings nor the structure of cluster monomer framework during polymerization reaction. Polymer-immobilized clusters were found to be active in hydrogenation reactions of cyclohexene.     

Vinyl polymerization. 275. Polymerization of vinyl monomers photosensitized by tetramethyltetrazene

A study of the photopolymerization of vinyl monomers in the presence of tetramethyltetrazene (TMT) was made. TMT was found to act as an effective sensitizer. In the photopolymerization of vinyl monomers such as methyl methacrylate or styrene the rate of polymerization was expressed by the equation: R_p = k[TMT]^1/2[monomer]. The chain-transfer constant of TMT under ultraviolet irradiation was estimated to be 3.8 × 10^?2 for the above monomers. A linear correlation was found to exist between the reactivity of dimethylamino radical toward the vinyl monomers and e values for the corresponding monomers.     

Radical copolymerization of sulfur dioxide and chloroprene

The radical copolymerization of sulfur dioxide and chloroprene (CP) in benzene was carried out, especially as a function of the total monomer concentration ([SO₂] + [CP]). The composition of chloroprene polysulfones varies mainly with total monomer concentration and with polymerization temperature, but depends very slightly on feed composition. The microstructure of chloroprene units in chloroprene polysulfone was such that the trans-1,4 unit was predominantly over the cis-1,4 unit. Thus it would seem possible to rule out both radical copolymerization mechanisms, i.e., propagation of separate monomers as explained by the Lewis-Mayo equation, and propagation processes involving a monomer charge-transfer complex.     

Studies on the copolymerization of norbornene with CO catalyzed by a new catalytic system PdCl<Subscript>2</Subscript>/phen/M(CF<Subscript>3</Subscript>SO<Subscript>3</Subscript>)<Subscript>n</Subscript>

A new three-component catalytic system, PdCl₂/phen/M(CF₃SO₃)_n where M = La, Y, Yb, Zn, and Cu, was studied for the copolymerization of norbornene (NBE) with CO to prepare polyketone (PK). It was found that the CF₃SO₃H catalytic system gave a low catalytic activity for the copolymerization of norbornene with CO, but when M(CF₃SO₃)_n was introduced instead of CF₃SO₃H, the PdCl₂/phen/M(CF₃SO₃)_n catalytic system exhibited much higher activity. The effects of ligands, M(CF₃SO₃)_n, solvents, and temperatures on the copolymerization have been discussed in detail. The results showed that with 1,10-phenanthroline (phen) and Cu(CF₃SO₃)₂ used as cocatalysts, the corresponding reaction rate reached 82 000 g PK (mol Pd)⁻¹h⁻¹ when the reaction was carried out in methanol at 90°C and 3.0 MPa of CO, and the weight average molecular weight (M _w) of the resultant copolymer is 1090 g/mol. The copolymer was characterized with various techniques such as FT-IR, ¹HNMR, ¹³CNMR, TGA, and DSC. The infrared spectrum of the product includes two features at 1697 and 1732 cm⁻¹ for the NBE/CO copolymer in CH₃OH that are attributed to carbonyl groups in ketones (repeating unit) and esters (end group), respectively. Due to the tension of the ring of norbornene, the degree of copolymerization is not high. Published in Russian in Kinetika i Kataliz, 2007, Vol. 48, No. 1, pp. 51–58. This article was submitted by the authors in English.     

Conventional free-radical and RAFT copolymerization of poly(ethylene oxide) containing macromonomers

Conventional free-radical and RAFT copolymerization of poly(ethylene oxide) substituent containing methacrylate macromonomers, PEO₅MEMA and PEO₄₅MEMA, was studied by the use of ¹H NMR spectroscopy for an analysis of residual monomers. From the monomer consumption curves, several parameters including monomer conversion, instantaneous copolymer composition and reactivity ratios of the monomers were evaluated. Reactivity ratios of PEO₅MEMA and MAA estimated by non-linear approach of error-in-variables model and presented as joint confidence regions were constant during conventional free-radical and RAFT copolymerizations of the above monomers but were slightly affected by the RAFT process. Reactivity ratio of PEO₄₅MEMA was found to be lower than that of PEO₅MEMA and varied during copolymerization: increased with conversion in conventional free-radical copolymerization and slightly (without confidence) decreased in the RAFT process. RAFT copolymerization of PEO₄₅MEMA and MAA enabled to synthesize comb copolymers with low composition distribution and more homogeneous distribution of PEO side chains along the mainchain. Under copolymerization with MAA, PEO₄₅MEMA behaved like typical macromonomer with appropriate steric hindrance while the behavior of PEO₅MEMA was similar to that of a low-molecular methacrylate.