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1.
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   

2.
5-(1-Adamantyloxy)-2H-pyrrole-2 one has been homopolymerized and copolymerized with a variety of comonomers. Polymerization was conducted in chloroform solutions with α,α′-azobisisobutyronitrile initiator. Evidence of polymerization was achieved through infrared and NMR spectra and elemental analysis. Moderate molecular weights were achieved as determined by inherent viscosity measurements and gel-permeation chromatography. Photolysis of the polymers with ultraviolet radiation induces a photochemical rearrangement resulting in the formation of isocyanate functions. A proposed mechanism suggests α-cleavage of the carbonyl to give a 1,5-diradical which rearranges to a 1,3-diradical with subsequent ring closure to give a polymer with cyclopropyl isocyanate moieties in the backbone. DSC data show all polymers to display intense exothermic activity at temperatures near 200°C on initial heating and glass transition temperatures between 194 and 245.5°C on subsequent heating. Thermolysis of the homopolymer causes rearrangement to poly[N-(1-adamantyl) maleimide]. Reactivity ratios were determined for the systems styrene (M1) and 5-(1-adamantyloxy)-2H-pyrrole-2-one (M2) (r1 = 0.06, r2 = 0.07) and methyl methacrylate (M1) and 5-(1-adamantyloxy)-2H-pyrrole-2-one(M2) (r1 = 0.35, r2 = 0.70). Q and e values for 5-(1-adamantyloxy)-2H-pyrrole-2-one are 3.40 and 1.59, respectively.  相似文献   

3.
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   

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.
Acrolein was copolymerized by radical initiation in aqueous solutions with sodium p-styrenesulfonate and acrylic acid, respectively, in the pH range of 3–7. The reactivities were shown to be pH-dependent. For the acrolein (M1)–sodium p-styrenesulfonate (M2) pair, r1 = 0.33 ± 0.15 and r2 = 0.32 ± 0.05 at pH 3; r1 = 0.23 ± 0.12 and r2 = 0.05 ± 0.03 at pH 5; r1 = 0.26 ± 0.03 and r2 = 0.025 ± 0.025 at pH 7. For the acrolein (M1)–acrylic acid (M2) pair, r1 = 0.50 ± 0.30 and r2 = 1.15 ± 0.2 at pH 3; r1 = 2.40 ± 0.50 and r2 = 0.05 ± 0.05 at pH 5; r1 = 6.70 ± 3.00 and r2 = 0.00 at pH 7. For acrolein, the new values of Q = 1.6 and e = 1.2 have been calculated. For sodium p-styrenesulfonate, the values Q = 0.76 and e = ?0.26 at pH 3, Q = 0.51 and e = ?0.87 at pH 5, Q = 0.39 and e = ?1.00 at pH 7 were obtained; and for acrylic acid, the values Q = 1.27 and e = 0.50 at pH 3, Q = 0.11 and e = ?0.22 at pH 5 were derived. The changes in reactivity are explained on the basis of inductive and resonance effects.  相似文献   

6.
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   

7.
Trimethylamine methacrylimide (TAMI) has been homo- and copolymerized with methyl methacrylate, vinyl acetate, vinyl chloride, hydroxypropyl methacrylate, and acrylonitrile by free-radical initiators to soluble, low molecular weight polymers containing pendant aminimide groups along the backbone of the polymer chains. The reactivity ratios in the copolymerization of TAMI (M1) with acrylonitrile (M2) were determined: r1 = 0.10 ± 0.01, r2 = 0.37 ± 0.04. The Alfrey-Price Q and e values for TAMI were also calculated: Q = 0.18, e = ?0.60. This preliminary work indicates that TAMI has potential for the preparation of reactive polymers.  相似文献   

8.
Photosensitized copolymerization of optically active N-l-menthylmaleimide (NMMI) with styrene (Sty) and methyl methacrylate (MMA) was carried out in tetrahydrofuran (THF) at 30°C with benzoyl peroxide (BPO). The monomer reactivity ratios for the copolymerization of NMMI (M2) with Sty (M1) and MMA (M1) were r1 = 0.08 ± 0.10, r2 = 0.20 ± 0.05 and r1 = 2.85 ± 0.06, r2 = 0.07 ± 0.06, respectively. Copoly-MMA–NMMI and poly-NMMI showed positive circular dichroism(CD) curves of equal intensity and shape over the wavelength region from 230 to 270 nm; copoly-Sty–NMMI also showed a positive CD curve which was similar in shape but was different in intensity from that of poly-NMMI. The correlation between monomer unit ellipticity of the copolymers and their composition would suggest the alternating and stereoregular copolymerization of NMMI with Sty.  相似文献   

9.
The polymerization and copolymerization of 2-phthalimidomethyl-1,3-butadiene were investigated. This monomer was easily polymerized by benzoyl peroxide catalyst in bulk or in solvent, and by γ-radiation in the solid state to give polymers having a softening point of 135–145°C. Although these resulting polymers did not give x-ray diffraction patterns, they showed crystalline patterns by electron diffraction. On the other hand, cationic polymerization with the use of boron trifluoride diethyl etherate in chloroform was attempted, but no formation of the polymer was observed. Also, this monomer was easily copolymerized with styrene in N,N-dimethylformamide. The monomer reactivity ratios and Alfrey-Price Q and e values calculated from the copolymerization data of this monomer (M1) with styrene (M2) were r1 = 2.0 ± 0.13, r2 = 0.15 ± 0.02, and Q1 = 2.78, e1 = 0.30.  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.
p-Styrenesulfonyl(β-chloroethyl)amide (III) was prepared and copolymerized with styrene (M1). The monomer reactivity ratios were determined (r1 = 0.25 = 0.1, r2 = 1.25 ± 0.25), and Q and e values were calculated (1.69 and 0.28, respectively). The polymer reacts with nucleophilic reagents such as amines and phenols in the presence of pyridine to the extent of 15–98%. Fibers from copolymers of acrylonitrile and III react with Congo Red in the presence of pyridine.  相似文献   

12.
Bulk radical copolymerization of methyl acrylate (MeA, M1) with styrene (St, M2) in presence and absence of ZnCl2 as complexing agent was studied. 1H-NMR spectra were used to establish copolymer composition and sequence distribution. The methoxy group signal was observed to be split due to pentads, but the analysis of sequence distribution is possible only at triad level. Both composition and sequence distribution data confirmed that bulk radical copolymerization respects quite well the terminal addition model; the values of r1 = 0.14 ± 0.02 (from composition data) and r1 = 0.25 ± 0.03 (from sequence distribution data) and r2 = 0.83 ± 0.10 (from composition data) were found. The presence of ZnCl2 increases the probability of alternating addition, e.g., for [ZnCl2]/[MeA] = 0.2, r1 = 0.03 ± 0.02 and r2 = 0.17 ± 0.03. The radical copolymer obtained in bulk in the absence of ZnCl2 presents a coisotactic configuration with σ = 0.75 ± 0.03, but the presence of the complexing agent reduces the probability of coisotactic addition, e.g., for [ZnCl2]/[MeA] = 0.2, σ = 0.52 ± 0.03.  相似文献   

13.
A newer approach to obtaining acrylic thermoset polymers with adequate hydrophilicity required for various specific end uses is reported. Glycidyl methacrylate (GMA) was copolymerized with n-butyl acrylate (n-BA), isobutyl acrylate (i-BA), and 2-ethylhexyl acrylate (2-EHA) in bulk at 60°C. with benzoyl peroxide as free radical initiator. The copolymer composition was determined from the estimation of epoxy group. Reactivity ratios were calculated by the Yezrielev, Brokhina, and Roskin method. For copolymerization of GMA (M1) with n-BA (M2) the reactivity ratios were r1 = 2.15 ± 0.14, r2 = 0.12 ± 0.03; with i-BA (M2) they were r1 = 1.27 ± 0.06, r2 = 0.33 ± 0.031; and with 2-EHA (M2) they were r1 = 2.32 ± 0.14, r2 = 0.13 ± 0.009. The reactivity ratios were the measure of distribution of monomer units in a copolymer chain; the values obtained are compared and discussed.  相似文献   

14.
Electrophilic trisubstituted ethylenes, ring-trisubstituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH = C(CN)CO2CH3 (where R is 2,4,6-trimethyl, 3,5-dimethoxy-4-hydroxy, 3,5-dimethyl-4-hydoxy, 3,4,5-trimethoxy, 2-bromo-3-hydroxy-4-methoxy, 5-bromo-2,3-dimethoxy, 5-bromo-2,4-dimethoxy, 6-bromo-3,4-dimethoxy were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-trisubstituted benzaldehydes and methyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r1) for the monomers is 5-bromo-2,3-dimethoxy (2.69) > 3,4,5-trimethoxy (1.86) > 6-bromo-3,4-dimethoxy (0.84) > 5-bromo-2,4-dimethoxy (0.39) > 4-hydoxy-3,5-dimethyl (0.31) = 2-bromo-3-hydroxy-4-methoxy (0.31) > 3,5-dimethoxy-4-hydroxy (0.24) > 2,4,6-trimethyl (0.22). Relatively high Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500ºC range with residue (1–6% wt), which then decomposed in the 500–800ºC range.  相似文献   

15.
Bis(hexafluoroisopropyl) fumarate (BHFIPF) did not homopolymerize with free radical initiators. However, BHFIPF yielded alternating copolymers with styrene in bulk with Azobisisobutyronitrile (AIBN) as a radical initiator. The monomer reactivity ratios of BHFIPF (M1) and styrene (M2) were calculated as r1 = 0.00 and r2 = 0.02. BHFIPF also copolymerized with vinyl pentafluorobenzoate (VPFB) in bulk and in pentafluoroisopropanol solution to produce an alternating copolymer. The reactivity ratios of BHFIPF (M1) with VPFB (M2) were r1 = 0.00 and r2 = 0.05 in bulk and r1 = 0.01 and r2 = 0.11 in pentafluoroisopropanol, respectively. The glass transition temperatures (Tg) of the BHFIPF‐styrene and BHFIPF‐VPFB copolymers were 107 and 86 °C, respectively. The BHFIPF‐styrene copolymer was thermally stable, and the thermal degradation temperature (Td) was 400 °C, whereas the Td of BHFIPF‐VPFB copolymer was 240 °C. The films obtained by casting from tetrahydrofuran (THF) solutions of these copolymers were flexible and transparent. Their refractive indices were 1.4048 for the BHFIPF‐styrene copolymer, and 1.3980 for the BHFIPF‐VPFB copolymer at 633 nm, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

16.
Polymerization behavior of meta-naphthoquinone methide, 3,4-benzo-6-methylenebicyclo[3.1.0]hex-3-ene-2-one ( 1 ), was studied. Radical initiator 2,2′-azobis(isobutyronitrile) (AIBN) induced polymerization of 1 , but ionic initiators potassium tert-butoxide, butyllithium, and boron trifluoride etherate did not. Polymerization of 1 proceeded via ring-opening and aromatization to give a polymer with head-to-tail monomer unit placement. Compound 1 copolymerized with methyl methacrylate (MMA) in the presence of AIBN to obtain the monomer reactivity ratios r1 ( 1 ) = 0.28 ± 0.07 and r2(MMA) = 0.39 ± 0.02 at 60°C and Q and e values of Q = 1.04 and e = −1.03, indicating that 1 is a conjugative and electron-donating monomer. Ring-opening and aromatization of 1 also took place in the copolymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 741–746, 1997  相似文献   

17.
The copolymerization of 3,4-dimethyltetrahydrofuran with selected cyclic ethers was studied. Although 3,4-dimethyltetrahydrofuran did not homopolymerize, it readily copolymerized with propylene oxide and epichlorohydrin in an alternating fashion using the cationic initiator PF5. The reactivity ratios r1 and r2 for the copolymerization of 3, 4-dimethyltetrahydrofuran and epichlorohydrin were r1 = 0.22 ± 0.05 and r2 = 0.11 ± 0.01, respectively.  相似文献   

18.
The copolymerization of 1,6-anhydro-2,3,4-tri-O-(p-methyl-benzyl)-β-D -glucopyrnose [TXGL, M1] with 1,6-anhydro-2,3-di-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-α-D -glucopyranosyl)-β-D -glucopyranose [HBMA, M2] has been studied as a method of producing dextrans of controlled composition with a linear backbone and randomly distributed single glucose units as side chains. Copolymers of intrinsic viscosities ranging from 0.51 to 0.05 dl/g are produced. The copolymerization appears to follow classical copolymerization theory but is affected adversely by the low reactivity of the maltose derivative. Reactivity ratios have been calculated for runs catalyzed by 10 mole-% and 20 mole-% phosphorus pentafluoride (PF5): r1 = 1.91 ± 0.35, r2 = 0.28 ± 0.25 and r1 = 2.21 ± 0.15, r2 = 0.21 ± 0.10, respectively.  相似文献   

19.
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   

20.
A method for the determination of reactivity ratios from conversion–composition data has been outlined. The conversion–composition changes during the copolymerization of styrene (M1) and methyl methacrylate (M2) have been studied at 60°C. By a method of graphical intersection, the integrated form of Skeist's equation has been used to determine the reactivity ratios (r1 = 0.54 ± 0.02 and r2 = 0.50 ± 0.06) in reasonably good agreement with values reported in the literature. The area of intersection was used as a measure of the precision of the data.  相似文献   

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