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1.
N.N. Messiha 《Polymer》1981,22(6):807-811
Copolymerization reactions were carried out in solution at 70°C in the presence of a free radical initiator, and the copolymer composition in each case was determined from tin analysis. The monomer reactivity ratios for the copolymerization reactions of tributyltin acrylate with vinyl acetate and N-vinylpyrrolidone were found to be: r1 = 2.567, r2 = 0.006 and r1 = 0.513, r2 = 0.610, respectively. Also, the copolymerization parameters of tributyltin methacrylate with vinyl acetate and N-vinylpyrrolidone were: r1 = 4.408, r2 = 0.017 and r1 = 3.160, r2 = 0.438, respectively. Four selected terpolymer feed compositions involving tributyltin acrylate or methacrylate with vinyl acetate or methyl methacrylate and N-vinylpyrrolidone or acrylonitrile, were polymerized to low conversion and the terpolymer composition in each case was calculated from tin and nitrogen analyses. The variations of terpolymer composition with conversion fit the experimental results over a wide range of conversion. The structure of the prepared co- and terpolymers was investigated by i.r. spectroscopy.  相似文献   

2.
Semicontinuous emulsion copolymerization of acrylonitrile (M1), butyl acrylate (M2), and styrene (M3) was investigated. The copolymerization proceeded under the conditions used with a high degree of conversion, whereby a stationary state characterized by a constant monomer mixture composition and a constant composition of the arising copolymer was achieved. From the analytically estimated free monomers and arising copolymer compositions, the reactivity ratios for the pair AN/BA r12 = 0.71, r21 = 1.17 and for the pair AN/Sty r13 = 0.06, r31 = 0.28 were calculated. The applicability of the reactivity ratios found was verified also for the ternary system acrylonitrile/butyl acrylate/styrene.  相似文献   

3.
The monomer reactivity ratios for the copolymerization of triphenyltin methacrylate with methyl acrylate, ethyl acrylate, and butyl acrylate have been found to be r1 = 2.58, r2 = 0.66, r1 = 2.37, r2 = 0.43, and r1 = 1.27, r0.39 = 0.39, respectively. also, the copolymerization parameters of triphenyltin methacrylate with methyl methacrylate and butyl methacrylate were as follows: r1 = 0.94, r2 = 0.99, and r1 = 0.68, r2 = 0.83, respectively. Copolymerization reactions were carried out in solution at 70°C using 1 mol % AIBN, and the copolymer compositions were determined by tin analysis. The sequence distribution of the alternating diad fractions for the systems studied were calculated at various feed compositions. The structure of the triphenyltin methacrylate monomer as well as its azeotropic copolymer with butyl methacrylate were investigated by IR spectroscopy.  相似文献   

4.
N.T. McManus 《Polymer》2004,45(17):5837-5845
The free radical initiated terpolymerization of butyl acrylate (BA), methyl methacrylate (MMA) and alpha methyl styrene (AMS) has been examined. Kinetic studies focused on elevated reaction temperatures (115 and 140 °C). The studies were made over the full conversion range and examined the effect of reaction temperature, feed composition and initiator level on reaction rates. The composition of terpolymer products and their molecular weights were also analyzed with respect to monomer conversion levels.  相似文献   

5.
Ternary copolymerization reactions of N-acryloyloxyphthalimide (NAP) or N-methacryloyloxyphthalimide (NMP) and acrylonitrile with methyl acrylate or methyl methacrylate were carried out in solution at 60°C in the presence of a free radical initiator. Experimental terpolymerization data agree well with calculations based on the Alfrey-Goldfinger equation. The determination of unitary, binary, and ternary azeotropies of the various systems studied was easily handled by a computer program. The results show that there is no ternary azeotropic composition for any terpolymer system studied. Selective unitary and binary azeotropic compositions were polymerized and the results show good agreement between the theoretical and experimental terpolymer composition in each case. The estimation of terpolymer compositions was carried out by 1H NMR spectroscopy.  相似文献   

6.
d ‐Limonene (Lim) is a renewable monoterpene derived from citrus fruit peels. We investigated it for use as part of a more sustainable polymer formulation. The bulk free‐radical terpolymerization of n‐butyl acrylate (BA)/butyl methacrylate (BMA)/Lim was carried out at 80°C with benzoyl peroxide as the initiator. The terpolymerization was studied at various initial BA/BMA/Lim molar ratios, and the products were characterized for conversion, terpolymer composition, molecular weight, and glass‐transition temperature. Lim was observed to undergo a significant degradative chain‐transfer reaction, which greatly influenced the polymerization kinetics. The rate of polymerization, final conversion, and polymer molecular weight were all significantly reduced because of the presence of Lim. Nonetheless, polymers with relatively high weight‐average molecular weights (20,000–120,000 Da) were produced. The terpolymer composition was well predicted with the reactivity ratios estimated for each of the three copolymer subsystems. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42821.  相似文献   

7.
Solution terpolymerization of styrene (Sty), acrylonitrile (AN) and copper acrylate (CuA) has been carried out in dimethylformamide at 90°C for 4 h using p-acetyl benzylidene triphenylarsonium ylide as radical initiator. 1H nuclear magnetic resonance (NMR), IR and elemental analysis have been used to characterized the terpolymer. Analysis of kinetic data indicates the following rate equation: The overall activation energy is 38 kJ mol−1. The composition of terpolymer calculated from NMR and elemental analysis has been used to evaluate reactivity ratios as r1(Sty) = 5 ± 2 and r2(AN + CuA) = 0.4 ± 0.02 employing the Finemann–Ross method, which confirms its random origin. The terpolymer was thermally stable up to 2007deg;C.  相似文献   

8.
Acrylonitrile–styrene–methyl methacrylate (A–S–M) terpolymers were prepared by photopolymerization using uranyl nitrate ions as photo initiators, which were analyzed by NMR spectroscopy. The terpolymer compositions were determined by Goldfinger's equation using comonomer reactivity ratios: ras = 0.04; rsa = 0.31; ram = 0.17, rma = 1.45; rsm = 0.52; rms = 0.47. The terpolymer compositions were also determined from the quantitative 13C(1H)‐NMR spectroscopy. The sequence distribution of the acrylonitrile‐, styrene‐, and methyl methacrylate–centered triads were determined from the 13C(1H)‐NMR spectra of the terpolymers and are in good agreement with triad concentrations calculated from the statistical model. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3026–3032, 1999  相似文献   

9.
Summary Copolymers of 5-vinyl-1, 3-benzodioxole (VBD) with n-butyl acrylate and methyl methacrylate were synthesized. The copolymers were synthesized according to a designed experiment methodology and reactivity ratios were estimated using a nonlinear least squares error-in-variables procedure. The values of r1 and r2 obtained show that VBD is slightly less reactive than styrene in similar copolymerization reactions.  相似文献   

10.
The butyl acrylate (BA)/methyl methacrylate (MMA), and glycidyl methacrylate (GMA) composite copolymer latex was synthesized by seeded emulsion polymerization technique taking poly(methyl methacrylate) (PMMA) latex as the seed. Four series of experiments were carried out by varying the ratio of BA : MMA (w/w) (i.e. 3.1 : 1, 2.3 : 1, 1.8 : 1, and 1.5 : 1) and in each series GMA content was varied from 1 to 5% (w/w). The structural properties of the copolymer were analyzed by FTIR, 1H‐, and 13C‐NMR. Morphological characterization was carried out using transmission electron microscopy (TEM). In all the experiments, monomer conversion was ~99% and final copolymer composition was similar to that of feed composition. The incorporation of GMA into the copolymer chain was confirmed by 13C‐NMR. The glass transition temperature (Tg) of the copolymer latex obtained from the differential scanning calorimetry (DSC) curve was comparable to the values calculated theoretically. With increase in GMA content, particles having core‐shell morphology were obtained, and there was a decrease in the particle size as we go from 2–5% (w/w) of GMA. The adhesive strength of the latexes was found to be dependent on the monomer composition. With increase in BA : MMA ratio, the tackiness of the film increased while with its decrease the hardness of the film increased. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

11.
Free‐radical copolymerization of 4‐nitrophenyl acrylate (NPA) with n‐butyl methacrylate (BMA) was carried out using benzoyl peroxide as an initiator. Seven different mole ratios of NPA and BMA were chosen for this study. The copolymers were characterized by IR, 1H‐NMR, and 13C‐NMR spectral studies. The molecular weights of the copolymers were determined by gel permeation chromatography and the weight‐average (M w) and the number‐average (M n) molecular weights of these systems lie in the range of 4.3–5.3 × 104 and 2.6–3.0 × 104, respectively. The reactivity ratios of the monomers in the copolymer were evaluated by Fineman–Ross, Kelen–Tudos, and extended Kelen–Tudos methods. The product of r1, r2 lies in the range of 0.734–0.800, which suggests a random arrangement of monomers in the copolymer chain. Thermal decomposition of the polymers occurred in two stages in the temperature range of 165–505°C and the glass transition temperature (Tg) of one of the systems was 97.2°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1817–1824, 2003  相似文献   

12.
N.E. Ikladious  A.F. Shaaban 《Polymer》1983,24(12):1635-1638
The monomer reactivity ratios for the copolymerization of methyl methacrylate (M1), styrene (M1), butyl acrylate (M1) and acrylamide (M1) with tri-n-butyltin maleate (M2) have been found to be r1 = 15.40, r2 = 0.01; r1 = 6.70, r2 = 0.05; r1 = 9.39, r2 = 0.11; and r1 = 122.44, r2 = 0.06, respectively. Also, the copolymerization parameters of acrylamide (M1) with tri-n-butyltin acrylate (M2) or methacrylate (M2) were as follows: r1 = 0.11, r2 = 0.82; and r1 = 1.46, r2 = 0.85, respectively. The Q and e values for the organotin monomers (tri-n-butyltin maleate, acrylate and methacrylate) were calculated from the monomer reactivity ratios determined in the present and previous studies. Copolymerization reactions were carried out in solution at 70°C using 1 mol% AIBN, and the copolymer compositions were determined by tin analysis. The structure of the tri-n-butyltin maleate and the prepared copolymers was investigated by i.r. spectroscopy.  相似文献   

13.
Reversible addition fragmentation chain transfer (RAFT) mediated and conventional miniemulsion copolymerizations of butyl methacrylate (BMA) with fluoromethacrylate (FMA) were carried out at 70°C with potassium persulphate as initiator. The kinetics of the copolymerizations was investigated comparatively. Copolymer compositions at low conversion levels were determined by 1H NMR and FTIR spectra techniques. In the presence of RAFT agent 2‐cyanoprop‐2‐yl dithiobenzoate, the copolymerization of BMA with FMA in miniemulsion was obviously retarded. The copolymerization exhibited typical features of controlled molecular weights and narrow polydispersities. The reactivity ratios were evaluated by Kellen‐Tudos (K‐T) method, which yields the apparent reactivity ratios: rBMA = 0.73 and rFMA = 0.75 in conventional copolymerizations, and rBMA = 0.65 and rFMA = 0.70 in CPDB‐mediated system. The results show that the monomer FMA with a perfluoroalkyl side chain is slightly more reactive than BMA, and the copolymerizations process have a tendency to crosspropagate and to produce a higher FMA content in the copolymers. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers  相似文献   

14.
Silicone‐modified styrene–butyl acrylate copolymer latex was synthesized by emulsion copolymerization by using octamethylcyclotetrasiloxane (D4), styrene, and butyl acrylate as raw materials, potassium persulfate as initiator and propylmethacrylate triethoxysilane (KH‐570) as crosslinking agent. The infrared spectra studies showed that the vinyl monomers were completely copolymerized with D4. The prepared silicone‐modified copolymer latex with the interpenetrating polymer networks tended to have higher stability, and better toluene and water resistance than styrene–butyl acrylate latex. The glossiness of coated paper was improved with silicone‐modified copolymer latex, and it was at a maximum when D4 was about 3% of total monomers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 333–336, 2001  相似文献   

15.
The effect of time, temperature, the concentration of initiator and emulsifier, and the ratio of starting polymer to monomer on the degree of conversion (MC) of styrene and the grafting efficiency (GE) of polystyrene has been investigated. The reaction was initiated with potassium persulphate. It has been found that the degree of conversion of styrene and the grafting efficiency change in opposite directions when plotted as functions of the reaction parameters studied. The graft copolymerization is assisted by short reaction times and weight ratios of poly(butyl acrylate) to styrene greater than unity. The results obtained suggest that higher grafting efficiencies are obtained when the concentration of emulsifier is below its c.m.c. (critical micellar concentration) value. When using two different anionic emulsifiers it has been observed that the effect of initiator concentration on the degree of conversion of styrene and the grafting efficiency is complicated. Both the quantities studied (MC and GE) exhibit extrema in the range of initiator concentration studied (3.7?33.3 × 10?5 mol dm?3 of H2O). No meaningful effect of temperature in the range 60°–90°C or that of dodecyl mercaptan (molecular weight regulator) used in an amount 0–0.4% in relation to poly(butyl acrylate) and styrene has been observed on the MC and GE values.  相似文献   

16.
Free radical copolymerization kinetics of 2‐(diisopropylamino)ethyl methacrylate (DPA) with styrene (ST) or methyl methacrylate (MMA) was investigated and the corresponding copolymers obtained were characterized. Polymerization was performed using tert‐butylperoxy‐2‐ethylhexanoate (0.01 mol dm?3) as initiator, isothermally (70 °C) to low conversions (<10 wt%) in a wide range of copolymer compositions (10 mol% steps). The reactivity ratios of the monomers were calculated using linear Kelen–Tüd?s (KT) and nonlinear Tidwell–Mortimer (TM) methods. The reactivity ratios for MMA/DPA were found to be r1 = 0.99 and r2 = 1.00 (KT), r1 = 0.99 and r2 = 1.03 (TM); for the ST/DPA system r1 = 2.74, r2 = 0.54 (KT) and r1 = 2.48, r2 = 0.49 (TM). It can be concluded that copolymerization of MMA with DPA is ideal while copolymerization of ST with DPA has a small but noticeable tendency for block copolymer building. The probabilities for formations of dyad and triad monomer sequences dependent on monomer compositions were calculated from the obtained reactivity ratios. The molar mass distribution, thermal stability and glass transition temperatures of synthesized copolymers were determined. Hydrophobicity of copolymers depending on the composition was determined using contact angle measurements, decreasing from hydrophobic polystyrene and poly(methyl methacrylate) to hydrophilic DPA. Copolymerization reactivity ratios are crucial for the control of copolymer structural properties and conversion heterogeneity that greatly influence the applications of copolymers as rheology modifiers of lubricating oils or in drug delivery systems. © 2015 Society of Chemical Industry  相似文献   

17.
《Polymer》1987,28(8):1423-1425
The monomer reactivity ratios for the copolymerization of di-(tri-n-butyltin) itaconate (M1) with methyl acrylate (M2), ethyl acrylate (M2), N-vinyl pyrrolidone (M2) and acrylonitrile (M2) were found to be r1 = 0.387, r2 = 0.671; r1 = 0.555, r2 = 0.958; r1 = 0.033, r2 = 0.185 and r1 = 0.441, r2 = 0.425, respectively. Copolymerization reactions were carried out in solution at 60°C using 1 mol% AIBN, with copolymer compositions being determined by tin analysis. The Q and e values for di-(tri-n-butyltin) itaconate were calculated from the monomer reactivity ratios determined in the present and previous studies. The sequence distribution of the triad fractions for the systems studied were calculated at azeotropic compositions.  相似文献   

18.
The homopolymerization and copolymerization of tert‐butyl methacrylate (tBMA) and norbornene (NB) with nickel(II) acetylacetonate in combination with methylaluminoxane were systematically investigated. This catalytic system showed high activity toward the homopolymerization of both NB and tBMA. For these copolymerizations, activity was gradually lost with an addition of tBMA to NB or of NB to tBMA. This result was qualitatively explained with the trigger coordination mechanism. Furthermore, the determination of the reactivity ratios indicated a significantly higher reactivity for NB than for tBMA (rNB = 4.14 and rtBMA = 0.097), and this was interpreted by the coordination mechanism. The synthesized acrylate/NB copolymers exhibited glass‐transition temperatures of 100–250°C. The absence of crystallinity and the homogeneous repartition of the monomer units along the main chain yielded products with high transparency and high stability © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1824–1833, 2004  相似文献   

19.
Summary 2-Vinylfuran (2VF) was copolymerized with methyl methacrylate and n-butyl acrylate according to an experimental design scheme. The results were analyzed with a nonlinear error-in-variables method. The values obtained for the reactivity ratios using this approach were much different than reactivity ratios obtained from conventional copolymerization experiments. The r1 and r2 values obtained in the present case indicate that 2VF has approximately the same reactivity as methyl methacrylate, but is much more reactive than n-butyl acrylate.  相似文献   

20.
Reverse atom transfer radical copolymerization of styrene (St) and butyl acrylate was carried out in emulsion under normal emulsion conditions, using CuBr2/bpy complex as catalyst. The effects of surfactant type, initiator type and concentration, and CuBr2 addition on the system livingness, polymer molecular weight control, and latex stability were examined in detail. It was found that the Polysorbate 80 (Tween 80) and azodiisobutyronitrile gave the best exhibition in this system, polymer samples were got with narrow molecular‐weight dispersity (Mw/Mn = 1.1–1.2) and linear relationships of molecular weight versus monomer conversion, as well as a relatively low polydispersity index (<0.1). Through the GPC and SEM analysis, the polymerization processes under these conditions showed good living/control characteristics relative to the processes under normal emulsion polymerization, although the latex stability was susceptible to the CuBr2 catalyst. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

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