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1.
Ferrocenylmethyl methacrylate (FMMA) was copolymerized with styrene (St), methyl methacrylate (MMA), and ethyl acrylate (EA) in benzene solution at 25°C by γ radiation. The reactions proceeded by a free radical mechanism, and monomer reactivity ratios were derived by the Tidwell–Mortimer method for St(M1)–FMMA(M2), r1 = 0.35 and r2 = 0.46; for MMA(M1–FMMA)(M2), r1 = 0.85 and r2 = 1.36; for EA(M1)–FMMA(M2), r1 = 0.36 and r2 = 3.03. The Q and e values of FMMA determined from copolymerization with St were 0.97 and 0.55, respectively. Terpolymerization of a MMA–FMMA–EA system based on the Alfrey–Goldfinger equations was studied. This is a typical terpolymerization system in which reactivities of the monomers obey the Qe scheme. Comparing the results obtained here with those previously reported for other monomers, we concluded that FMMA is one of the most highly reactive monomers among alkyl methacrylates.  相似文献   

2.
The polymerization of trimethylvinylgermane (TMGeV) with the use of γ-ray, radical, and ionic initiator was attempted, but homopolymer was not obtained. This monomer did not undergo polymerization by itself, but polymerized with high concentration of n-BuLi. Copolymerization of TMGeV with styrene (St) and methyl methacrylate (MMA) was carried out by using radical initiator. From the results obtained by the copolymerization, monomer reactivity ratios and Qe values were obtained as follows: for the system St(M1)–TMGeV (M2), r1 = 24.4, r2 = 0.009, Q2, = 0.0049, e2 = 0.43; for the system MMA (M1)–TMGeV (M2), r1 = 19.98, r2 = 0.05; Q2 = 0.037, e2 = 0.43., The polymerizability of TMGeV is discussed on the basis of the Q and e values obtained.  相似文献   

3.
Trimethylamine-4-vinylbenzimide (TAVBI) has been homo- and copolymerized with styrene, methyl methacrylate, and hydroxypropyl methacrylate by free-radical initiators to soluble, low molecular weight polymers containing pendant aminimide groups along the backbone of the polymer molecules. The reactivity ratios in the copolymerization of TAVBI (M1) with styrene (M2) were determined: r1 = 0.63 ± 0.07, r2 = 0.47 ± 0.05. The Alfrey-Price Q and e values for TAVBI were also calculated: Q = 0.88, e = 0.31. This introductory work indicates that TAVBI has potential for the preparation of a wide variety of reactive polymers.  相似文献   

4.
Optically active mono-l-menthyl itaconate (MMI) was prepared from ita-conic acid and l-menthol. MMI was polymerized in bulk at 80°C to give a chiral homopolymer having -49.5° specific rotation. MMI (M1 was copolymerized with styrene (ST, M2), methyl methacrylate (MMA, M2), and N-cyclohexylmaleimide (CHMI, M2) by using 2,2′-azobisisobutyronitrile (AIBN) as the radical initiator and benzene as the polymerization solvent at 50°C. The monomer reactivity ratios (r1, r2) and Alfrey-Price Q, e values were determined to be r1 = 0.28, r2 = 0.32, Q1 = 0.90, and e1 = 0.75 in MMI-ST; r1 = 0.09 and r2 = 0.51 in MMI-MMA; and r1 = 0.78 and r2 = 0.39 in MMI-CHMI. The chiroptical properties of the polymers were investigated.  相似文献   

5.
Radical homo- and copolymerizations of methyl α-trifluoroacetoxyacrylate (MTFAA) are studied by using azo initiators at 40 and 60°C. The rate of the homopolymerization of MTFAA was lower than that of methyl α-acetoxyacrylate. Monomer reactivity ratios (r), and Q and e values were estimated to be r1 = 0.03, r2 = 0.27, Q1 = 0.65, and e1 = 1.38 from the copolymerization of MTFAA (M1) and styrene (M2) at 60°C. Preferential crosspropagation was observed in particular in the copolymerization of MTFAA and α-methylstyrene. The influence of replacing the hydrogens of the acetoxy moiety of the acyloxyacrylate with the fluorines upon the copolymerization reactivity is discussed on the basis of the 13C-NMR chemical shift of various acyloxyacrylates. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3537–3541, 1997  相似文献   

6.
α-Trimethylsilyloxystyrene (TMSST), the silyl enol ether of acetophenone, was not homopolymerized either by a radical or a cationic initiator. Radical copolymerization of TMSST with styrene (ST) and acrylonitrile (AN) in bulk and the terpolymerization of TMSST, ST, and maleic anhydride (MA) in dioxane were studied at 60°C and the polymerization parameters of TMSST were estimated. The rate of copolymerization decreased with increased amounts of TMSST for both systems. Monomer reactivity ratios were found as follows: r1 = 1.48 and r2 = 0 for the ST (M1)–TMSST (M2) system and r1 = 0.050 and r2 = 0 for the AN (M1)–TMSST (M2) system. The terpolymerization of ST (M1), TMSST (M2), and MA (M3) gave a terpolymer containing ca. 50 mol % of MA units with a varying ratio of TMSST to ST units and the ratio of rate constants of propagation, k32/k31, was found to be 0.39. Q and e values of TMSST were determined using the values shown above to be 0.88 and ?1.13, respectively. Attempted desilylation by an acid catalyst for the copolymer of TMSST with ST afforded polystyrene partially substituted with hydroxyl groups at the α-position.  相似文献   

7.
The benzene solution homopolymerization of vinylferrocene, initiated by azobisisobutyronitrile, gave a series of benzene-soluble homopolymers. Thus, free-radical copolymerization studies were performed with styrene, methyl acrylate, methyl methacrylate, acrylonitrile, vinyl acetate, and isoprene in benzene. With the exception of vinyl acetate and isoprene, which did not give copolymers with vinylferrocene under these conditions, smooth production of copolymers occurred. The relative reactivity ratios, r1 and r2, were obtained for vinylferrocene–styrene copolymerizations by using the curve-fitting method for the differential form of the copolymer equation, by the Fineman-Ross technique, and by computer fitting of the integrated form of the copolymer equations applied to higher conversion copolymerizations. In styrene (M2) copolymerizations, the curve-fitting and Fineman-Ross methods both gave r1 = 0.08, r2 = 2.50, while the integration method gave r1 = 0.097, r2 = 2.91. Application of the integration method to methyl acrylate and methyl methacrylate (M2) gave values of r1 = 0.82, r2 = 0.63; r1 = 0.52, r2 = 1.22, respectively. The curve-fitting method gave r1 = 0.15, r2 = 0.16 for acrylonitrile (M2) copolymerizations. From styrene copolymerizations, vinylferrocene exhibited values of Q = 0.145 and e = 0.47.  相似文献   

8.
Copolymers of 2-sulfoethyl methacrylate, (SEM) were prepared with ethyl methacrylate, ethyl acrylate, vinylidene chloride, and styrene in 1,2-dimethoxyethane solution with N,N′-azobisisobutyronitrile as initiator. The monomer reactivity ratios with SEM (M1) were: vinylidene chloride, r1 = 3.6 ± 0.5, r2 = 0.22 ± 0.03; ethyl acrylate, r1 = 3.2 ± 0.6, r2 = 0.30 ± 0.05; ethyl methacrylate, r1 = 2.0 ± 0.4, r2 = 1.0 ± 0.1; styrene, r1 = 0.6 ± 0.2, r2 = 0.37 ± 0.03. The values of the copolymerization parameters calculated from the monomer reactivity ratios were e = +0.6 and Q = 1.4. Comparison of the monomer reactivities indicates that SEM is similar to ethyl methacrylate with regard to copolymerization reactivity in 1,2-dimethoxyethane solution. The sodium salt of 2-sulfoethyl methacrylate, SEM?Na, was copolymerized with 2-hydroxyethyl methacrylate (M2) in water solution. Reactivity ratios of r1 = 0.7 ± 0.1 and r2 = 1.6 ± 0.1 were obtained, indicating a lower reactivity of SEM?Na in water as compared to SEM in 1,2-dimethoxyethane. This decreased reactivity was attributed to greater ionic repulsion between reacting species in the aqueous medium.  相似文献   

9.
Optically active di-L-menthyl itaconate (DMI) was prepared from itaconic acid and L-menthol. DMI was polymerized in bulk at 80°C to give a chiral homopolymer having a specific rotation of -76.9°. DMI (M 1) was copolymerized with styrene (ST, M 2), N-cyclohexylmaleimide (CHMI, M 2), vinyl acetate (VAc, M 2) and methyl methacrylate (MMA, M 2) with azobisisobutyronitrile in benzene at 50°C. The monomer reactivity ratios (r 1, r 2) and Alfrey-Price Q, e values were determined as r 1 = 0.56, r 2 = 0.55, Q 1 = 0.76, e 1 = 0.29 for DMI-ST; r 1 = 0.0, r 2 = 5.6 for DMI-MMA; r 1 = 0.0, r 2 = 0.25 for DMI-VAc; and r 1 = 0.31, r 2 = 0.56 for DMI-CHMI. The chiroptical properties of the polymers were investigated.  相似文献   

10.
Copolymers of 2-hydroxyethyl acrylate, hydroxypropyl acrylate, and 2(1-aziridinyl)-ethyl methacrylate (M2) with styrene (M1) were prepared in benzene solution at 60°C. Benzoyl peroxide, 0.1–0.2 mole-%, was used as initiator. Copolymer samples with the molar concentrations of M2 feed ranging from 0.10 to 0.85 were used to determine the reactivity ratios. Elemental analysis and nuclear magnetic resonance spectroscopy (NMR) were used to determine copolymer compositions. There was a solubility problem when the latter technique was applied. When samples which were completely soluble were analyzed, the results obtained from NMR and elemental analysis were in excellent agreement. The monomer reactivity ratios and the corresponding parameters for the copolymerization of (M1) with 2-hydroxyethyl acrylate are: r1 = 0.38 ± 0.02, r2 = 0.34 ± 0.03; Q2 = 0.85, e2 = 0.64; with hydroxypropyl acrylate are: r1 = 0.45 ± 0.03, r2 = 0.36 ± 0.03; Q2 = 0.75, e2 = 0.56; with 2(1-aziridinyl)ethyl methacrylate are: r1 = 0.53 ± 0.02, r2 = 0.63 ± 0.04; Q2 = 0.82, e2 = 0.25.  相似文献   

11.
The kinetics of methacryloyl fluoride (MAF) homopolymerization was investigated in methyl ethyl ketone (MEK) with azobis(isobutyronitrile) as initiator. The rate of polymerization (Rp) followed the expression Rp = k[AIBN]0.55[MAF]1.18. The overall activation energy was calculated as 74.4 kJ/mol. The relative reactivity ratios of MAF(M2) copolymerization with styrene (r1 = 0.083, r2 = 0.14), and methyl methacrylate (r1 = 0.48, r2 = 0.81) in methyl ethyl ketone were obtained. Application of the Qe scheme (in styrene copolymerization) led to Q = 2.22 and e = 1.31. The glass transition temperature (Tg) of poly(MAF) was 90°C by thermomechanical analysis. Thermogravimetry of poly(MAF) showed a 10% weight loss of 228°C in air.  相似文献   

12.
New vinylsilanes (M2), i. e. phenylvinylsilane (I), allylmethylsilane (II), allylphenylsilane (III), and p-vinylphenylmethylsilane (IV), were prepared and copolymerized with styrene (M1). The monomer reactivity ratios were r1 = 5.7 and r2 = 0, r1 = 36 and r2 = 0, r1 = 29 and r2 = 01, and r1 = 0.91 and r2 = 1.1, respectively. From the results of infrared and NMR spectra it was indicated that the vinylsilanes participated in copolymerization in the form of a vinyl type of polymerization and not in the form of a hydrogen-transfer type of polymerization. The reaction of copolymer with alcohols and methyl methacrylate and appropriate catalysts was investigated.  相似文献   

13.
Styrene copolymerized with dimethyl itaconate and with methyl benzyl itaconate by use of a free radical initiator.

Monomer reactivity ratios for styrene (M1)-dimethyl itaconate (M2) co-polymerization were r1 = 0.50 and r2 = 0.06 and for styrene (M1-methyl benzyl itaconate (M2), r1 = 0.42 and r2 = 0.19. The nonconjugative methoxycarbonyl affected the monomer reactivity of itaconate toward polystyrene radical.

The NMR spectra of styrene-dimethyl itaconate copolymers were very complex and could not be interpreted because the two methoxy groups have similar chemical shifts.

The NMR spectra of styrene-itaconate copolymers were not so complex if methyl benzyl itaconate was used as comonomer instead of dimethyl itaconate. Methoxy and benzyloxy absorptions were sufficiently separated and “co-isotacticity” could be determined.

It is shown that the nonconjugative methoxycarbonyl group had little influence on the steric course of the cross-propagation reaction between styrene and itaconate.  相似文献   

14.
A new type of optically active N-(L-menthylcarboxylatomethyl)maleimide (MGMI) was synthesized from maleic anhydride, glycine, and L-menthol. Radical homopolymerization of MGMI was performed at 50°C for 24 h to give optically active polymer having [α]D = -57°. Radical copolymerizations of MGMI (M 1) were performed with styrene (ST, M 2), methyl methacrylate (MMA, M 2) in benzene at 50°C. From the results, the monomer reactivity ratios (r 1, r 2) and the Alfrey-Price Q, e values were determined as follows: r 1 = 0.16, r 2 = 0.006 for the MGMI-ST system; r 1 = 0.15, r 2 = 1.65 for the MGMI-MMA system, and Q 1 = 0.72, e 1 = 1.59 calculated from the MGMI-MMA system. Anionic homopolymerizations of MGMI were also carried out. Chiroptical properties of the polymers were investigated.  相似文献   

15.
The kinetics of cyanomethyl methacrylate (CyMA) homopolymerization was investigated in acetonitrile with azobisisobutyronitrile as initiator. The rate of polymerization Rp was expressed by Rp = k[AIBN]0.49[CyMA]1.2 and the overall activation energy was calculated as 72.3 kJ/mol. Kinetic constants for CyMA polymerization were obtained as follows: kp/k = 0.10 L1/2s?1/2; 2fkd = 1.57 × 10?5s?. The relative reactivity ratios of CyMA(M2) copolymerization with styrene (r1 = 0.15, r2 = 0.29) and methyl methacrylate (r1 = 0.43, r2 = 0.75) in acetonitrile were obtained. Applying the Q-e scheme (in styrene copolymerization) led to Q = 1.64 and e = 0.98. The glass transition temperature Tg of poly(CyMA) was observed to be 91°C by thermomechanical analysis. Thermogravimetry of poly(CyMA) showed a 10% weight loss at 265°C in air.  相似文献   

16.
The polymerizations of trimethylvinyltin (TMSnV) and tributylvinyltin (TBSnV) were carried out with the use of γ-ray, radical, or ionic initiators. These monomers did not undergo the polymerization by themselves, but they did copolymerize with styrene (St) or methyl methacrylate (MMA) when a radical initiator was used. From the results obtained by the copolymerization, monomer reactivity ratios and Q–e values were obtained as follows: for the system St(M1)? TMSnV, r1 = 44.8, r2 = 0.001, Q2 = 0.005, e2 = 0.962; for the system MMA (M1)? TMSnV, r1 = 25.1, r2 = 0.03, Q2 = 0.036, e2 = 0.933; for the system St(M1)? TBSnV, r1 = 16.0, r2 = 0.005, Q2 = 0.017, e2 = 0.822; for the system MMA(M1)? TBSnV, r1 = 27.9, r2 = 0.03, Q2 = 0.031, e2 = 0.822. The abilities of TMSnV and TBSnV to polymerize are discussed on the basis of the Q and e values obtained.  相似文献   

17.
N-phenyl-α-methylene-β-lactam (PML), a cyclic analog of N,N-disubstituted methacrylamides which do not undergo radical homopolymerization, was synthesized and polymerized with α,α′-azobis (isobutyronitrile) (AIBN) in solution. Poly (PML) (PPML) is readily soluble in tetrahydrofuran, chloroform, pyridine, and polar aprotic solvents but insoluble in toluene, ethyl acetate, and methanol. PPML obtained by radical initiation is highly syndiotactic (rr = 92%), exhibits a glass transition at 180°C, and loses no weight upto 330°C in nitrogen. The kinetics of PML homo-polymerization with AIBN was investigated in N-methyl-2-pyrrolidone. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.55[PML]1.2 and the overall activation energy has been calculated to be 87.3 kJ/mol. Monomer reactivity ratios in copolymerization of PML (M2) with styrene (M1) are r1 = 0.67 and r2 = 0.41, from which Q and e values of PML are calculated as 0.60 and 0.33, respectively.  相似文献   

18.
3-Methylene-5,5′-dimethyl-2-pyrrolidinone (α-MDMP), a cyclic analog of N-substituted methacrylamide, was synthesized and polymerized with α,α′-azobis (isobutyronitrile) (AIBN) in solution. Poly(α-MDMP) is only soluble in dimethyl sulfoxide (DMSO) at room temperature. Thermogravimetry of poly(α-MDMP) showed 10% weight loss at 355°C in air and 400°C under nitrogen, respectively. The kinetics of α-MDMP homopolymerization with AIBN was investigated in DMSO. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.49[α-MDMP]1.0 and the overall activation energy has been calculated to be 73.2 kJ/mol. Monomer reactivity ratios in copolymerization of α-MDMP (M2) with methyl methacrylate (M1) are r1 = 0.71 and r2 = 0.71, from which Q and e values of α-MDMP are calculated as 0.75 and -0.43, respectively. © 1993 John Wiley & Sons, Inc.  相似文献   

19.
The copolymerization of vinylhydroquinone (VHQ) and vinyl monomers, e.g., methyl methacrylate (MMA), 4-vinyl-pyridine (4VP), acrylamide (AA), and vinyl acetate (VAc), by tri-n-butylborane (TBB) was investigated in cyclohexanone at 30°C under nitrogen. VHQ is assumed to copolymerize with MMA, 4VP, and AA by vinyl polymerization. The following monomer reactivity ratios were obtained (VHQ = M2): for MMA/VHQ/TBB, r1 = 0.62, r2 = 0.17; for 4VP/VHQ/TBB, r1 = 0.57, r2 = 0.05; for AA/VHQ/TBB, r1 = 0.35, r2 = 0.08. The Q and e values of VHQ were estimated on the basis of these reactivity ratios as Q = 1.4 and e = ?;1.1, which are similar to those of styrene. This suggests that VHQ behaves like styrene rather than as an inhibitor in the TBB-initiated copolymerization. No homopolymerization was observed either under nitrogen or in the presence of oxygen. The reaction mechanism is discussed.  相似文献   

20.
The copolymerization of 4-cyclopentene-1,3-dione (M2) with p-chlorostyrene and vinylidene chloride is reported. The copolymers were prepared in sealed tubes under nitrogen with azobisisobutyronitrile initiator. Infrared absorption bands at 1580 cm.?1 revealed the presence of a highly enolic β-diketone and indicated that copolymerization had occurred. The copolymer compositions were determined from the chlorine analyses and the reactivity ratios were evaluated. The copolymerization with p-chlorostyrene (M1) was highly alternating and provided the reactivity ratios r1 = 0.32 ± 0.06, r2 = 0.02 ± 0.01. Copolymerization with vinylidene chloride (M1) afforded the reactivity ratios r1 = 2.4 ± 0.6, r2 = 0.15 ± 0.05. The Q and e values for the dione (Q = 0.13, e = 1.37), as evaluated from the results of the vinylidene chloride case, agree closely with the previously reported results of copolymerization with methyl methacrylate and acrylonitrile and confirm the general low reactivity of 4-cyclopentene-1,3-dione in nonalternating systems.  相似文献   

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