Terpolymerization System Research Articles

A systematic study of tert‐butylacrylamide‐methyl acrylate‐acrylic acid radical solution terpolymerization

AbstractMulti‐functional polymers used for personal care products can be synthesized by radical polymerization of acrylic acid (AA) in alcohol/water solutions with non‐functional monomers such as methyl acrylate (MA) and N‐tert‐butylacrylamide (t‐BuAAm). However, solvents capable of forming or disrupting hydrogen bonds cause the polymerization kinetics of these monomers to deviate from their polymerization behaviour in bulk and non‐polar solvents. In this work, a previous mechanistic model developed for MA/t‐BuAAm copolymerization is extended to represent the terpolymerization system MA/t‐BuAAm/AA. The additional kinetic coefficients required for the system are estimated from fitting to AA homopolymerizations and AA/MA and AA/t‐BuAAm copolymerizations conducted in an ethanol/water solution. In‐situ nuclear magnetic resonance (NMR) spectroscopy is used to follow monomer conversions and composition drift behaviour, with the molar mass distributions of the polymer products characterized by size‐exclusion chromatography. Although AA is more reactive than MA in non‐polar solvents, the reactivities of the two monomers equalize under the experimental conditions examined. Thus, the batch and semi‐batch terpolymerization data collected are represented equally well by a reduced acrylate/t‐BuAAm copolymerization model and the full terpolymerization implementation.

Insertion of ester bonds in three terpolymerization systems

Nonbiodegradable (co)polymers with all-carbon backbone produced via radical polymerization are used in various applications. For some applications, like for example in skincare and haircare, these polymers are nonrecoverable and therefore would be preferably made biodegradable. Therefore, inserting ester bonds in the backbone via radical ring opening terpolymerization of acrylates and 2-methylene-1,3 dioxepane (MDO) could be a suitable approach to obtain biodegradable terpolymers. This report investigates the influence of batch versus semibatch process on the polymerization of three terpolymerization systems viz. (i) methacrylamide (MAAM)/n-butyl acrylate (nBA)/BMDO (5,6-Benzo-2-Methylene-1,3-Dioxepane), (ii) MAAM/nBA/MDO, and (iii) methyl methacrylate (MMA)/VAc (vinyl acetate) /MDO. We demonstrate the improvement in number of ester groups inserted and the homogeneity of insertion via semibatch polymerization processes. The process is guided via optimal monomer addition feeding profiles generated using the reactivity ratios of comonomers. Such improved insertion was demonstrated by the molecular weight distribution of fragments after alkali degradation in the investigated systems.

Analysis of Terpolymerization Systems for the Development of Carbon Fiber Precursors of PAN

The thermal stabilization of polyacrylonitrile fibers (FPAN) is one of the most important steps in the production of carbon fibers (CFs). In this paper, new precursor polymers from PAN have been synthesized with different chemical characteristics using a solution polymerization, and FPAN was obtained using an unconventional wet spinning system in the drying and collapsing steps. The effect of different operation conditions, comonomers, and termonomers on the properties of precursor polymers, polymerization reactions, mechanical properties, structural characteristics, and stabilization of the FPAN was studied and analyzed. FTIR and optical microscopy were used to analyze structural changes of FPAN in the thermal stabilization. The impact of the chemical composition of the precursor polymers on the physicochemical characteristics of FPAN and their behavior in the thermal stabilization process were evaluated. In particular, itaconic acid termonomer improved the tensile strength of the fibers from 8.07 to 16.87 cN/dtex, and the extent stabilization increased from 1.81 to 4.6. FTIR indicated that the reaction of stabilization of the terpolymer developed was initiated at a lower temperature compared to that of a commercial precursor polymer.

Catalyst-Free and Low-Temperature Terpolymerization in a Single-Component Benzoxazine Resin Containing Both Norbornene and Acetylene Functionalities

Multicomponent copolymerization is an efficient approach for balancing the processability and thermal and mechanical properties of polymers. However, the copolymerization system has rarely been observed in single component resins. Here we report a terpolymerization system in a novel ortho-norbornene functional benzoxazine containing acetylene group (oHPNI-ac), where the chemical structures of oHPNI-ac are confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The polymerization behaviors are investigated by differential scanning calorimetry (DSC), in situ FT-IR, and solid-state 13C NMR. In addition to the polymerization of the oxazine ring and acetylene group, oHPNI-ac exhibits an unexpected lower thermally activated polymerization temperature of norbornene functionality compared with other reported norbornene containing monomers or oligomers. Furthermore, rheological measurements are applied to reveal the evolution of the rheological beh...

Binary vs. ternary reactivity ratios: Appropriate estimation procedures with terpolymerization data

There is a widely accepted analogy between copolymerization and terpolymerization mechanisms that has allowed researchers to use reactivity ratios obtained for binary pairs (from copolymerization experiments) in models dealing with terpolymerizations. However, binary reactivity ratios are not always applicable to terpolymerization systems; using the binary-ternary analogy (even as an approximation) requires making considerable assumptions about the system. When binary reactivity ratios are used to describe ternary systems, the consequences may include substantial differences in reactivity ratio estimates, poor composition prediction performance, and incorrect determination of product (terpolymer) characteristics. Experimental results and reactivity ratio estimation (via the error-in-variables-model) for the terpolymerization of 2-acrylamido-2-methylpropane sulfonic acid (AMPS), acrylamide (AAm) and acrylic acid (AAc) (and associated copolymers) are compared, all other conditions being equal.

Demystifying the estimation of reactivity ratios for terpolymerization systems

In typical practice for terpolymerizations so far, binary reactivity ratios have been used directly in the instantaneous Alfrey and Goldfinger (AG) model, effectively ignoring the presence of the third monomer. In addition, the use of the AG model leads to severe estimation problems, if one would like to estimate reactivity ratios from experimental data. Due to the above reasons, the AG model was recast and was subsequently used with terpolymerization data directly to estimate ternary reactivity ratios under the error‐in‐variables‐model framework, based both on instantaneous (low conversion) and cumulative composition data (medium and high conversions). Several examples and counter examples highlight such important issues as the choice of the correct number of responses, accounting for the appropriate error structure, and incorporating the right information content, all with diagnostic checks whose target is the eventual reliability of the reactivity ratio estimates. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1752–1766, 2014

Terpolymerization kinetics of methyl methacrylate or styrene/dodecyl methacrylate/octadecyl methacrylate systems

AbstractThis study describes low‐conversion terpolymerization kinetic investigations of methyl methacrylate/dodecyl methacrylate/octadecyl methacrylate (MMA/DDMA/ODMA) and styrene/dodecyl methacrylate/octadecyl methacrylate (ST/DDMA/ODMA) systems. Terpolymerizations were performed isothermally (70–105 °C), in 1 mol dm−3 xylene solutions, using 0.01 mol dm−3 of bifunctional peroxide initiator 1,1‐di(tert‐butylperoxy)‐3,3,5‐trimethylcyclohexane or monofunctional tert‐butylperoxy‐2‐ethylhexanoate. Synthesized terpolymers were characterized with respect to composition and molar mass distribution. Initial polymerization reaction rates as well as terpolymer average molar masses decreased with increasing MMA or ST content in the monomer mixture, for both initiators and all investigated temperatures. Overall reaction rates were found to be significantly larger for the MMA/DDMA/ODMA system. In the MMA/DDMA/ODMA system, experimental terpolymer compositions were found to be similar to the initial monomer feed compositions—all the experimental monomer feed mixtures were close to the azeotropic composition. The Alfrey–Goldfinger terpolymerization equation was successfully used for the description of MMA/DDMA/ODMA terpolymerization kinetics, where the existence of the true azeotropic ternary point was established. The same equation did not perform as well for the ST/DDMA/ODMA terpolymerization system. Copyright © 2006 Society of Chemical Industry

Terpolymerization with depropagation: Modelling the copolymer composition of the methyl methacrylate/alpha-methylstyrene/butyl acrylate system

The kinetics of the free radical terpolymer system methyl methacrylate (MMA)/alpha methyl styrene (AMS)/butyl acrylate (BA) have been studied in detail. Previous work with terpolymer systems typically has not involved monomers or cases where depropagation was a significant concern and hence the Alfrey–Goldfinger model was adequate to describe the system. In other works involving the MMA/AMS/BA system, modelling of the kinetics has not been attempted. In order to properly study this system, a new model has been developed based upon some of the underlying principles of the binary Kruger model (Kruger et al., 1987. Ein modell zur beschreibung reversibler copolymerisationen. Makromolecular Chemie, 188, 2163–2175.). A sensitivity analysis and benchmarking of the new model has been done and the terpolymerization system has been studied at 140 ∘ C for selective feed ratios with promising results.

Mathematical modeling of diffusion-controlled free-radical terpolymerization reactions

A comprehensive mathematical model is developed to describe the kinetics and molecular and compositional developments in a free-radical terpolymerization batch reactor. This model is based on a fairly general kinetic mechanism, including chain-transfer and terminal double-bond reactions. We take into account the effects of diffusion-controlled phenomena (i.e., gel, glass, and cage effects) on polymerization kinetics by extending our previous model on diffusion-controlled reactions to terpolymerization systems. Triple moments for the live and dead trivariate chain-length terpolymer composition distributions are introduced to describe the molecular and compositional developments in the terpolymerization system. The predictive capabilities of this model are demonstrated by simulation of the free-radical, bulk terpolymerization of butyl acrylate/methyl methacrylate/vinyl acetate under different experimental conditions. It is shown that the model predictions are in good agreement with experimental data on monomer conversion, average molecular weights, and terpolymer composition, as reported by Dube and Penlidis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 161–176, 2003

Modelling the molecular weight distribution in terpolymerization systems with donor–acceptor complexes

Abstract In this work we present, for the first time, a mathematical development of the moments of the molecular weight distribution in terpolymerization systems where donor–acceptor complexes are formed and the propagating reactions are carried out according to the complex participation model. The resulting set of equations is applied to the system formed by vinyl chloride (VC), vinyl acetate (VAc) and maleic anhydride (MA), in order to show the use of the equations and the type of information that might be obtained from them.

Nonlinear State Estimation and Control of a Semibatch Terpolymerisation Reactor

A nonlinear closed loop controller is designed for semicontinuous emulsion terpolymerization systems. The objective of the controller is to simultaneously maintain the production at a maximum rate and to ensure homogeneous composition during the process. A high gain non-linear observer is used to estimate the polymer composition, which is needed to calculate the controller action. A static input/output linearizing state feedback is developed for manipulating the feed rates of monomers to control the concentration of monomer in the reactor. The controller was studied by simulating the butyl acrylate, methyl acrylate and vinyl acetate emulsion terpolymerization processes.

Emulsion co- and terpolymerization of styrene, methyl methacrylate, and methyl acrylate. I. Experimental determination and model prediction of composition drift and microstructure in batch reactions

In Part I of this series the reactivity ratios of the comonomer pair methyl acrylate-methyl methacrylate were determined with low-conversion bulk polymerizations. It was shown that the binary reactivity ratios of the systems styrene-methyl acrylate, styrene-methyl methacrylate, and methyl acrylate-methyl methacrylate describe composition drift in low-coversion bulk terpolymerizations with these monomers reasonably well. A computer model was developed to simulate the composition drift in emulsion co- and terpolymerizations. The composition drift in two batch emulsion copolymerization systems (styrene-methyl acrylate and methyl acrylate-methyl methacrylate) and one emulsion terpolymerization system (styrene-methyl acrylate-methyl methacrylate) was investigated both experimentally and with the model. Experimental results were compared with model calculations. The copolymer chemical composition distributions (CCD) were determined with gradient polymer elution chromatography (GPEC®). This technique was also used for the first time to obtain information about the extent of composition drift in emulsion terpolymerizations. Cumulative terpolymer compositions were determined with 3H-NMR as a function of conversion and with this information the three-dimensional CCD was obtained. The composition drift was analyzed with respect to free radical copolymerization kinetics (reactivity ratios) and monomer partitioning. It was shown that in most emulsion copolymerizations the composition drift is mainly determined by the reactivity of the monomers and to a lesser extent by monomer partitioning, except in systems where there is a large difference in water solubility. The model predictions for cumulative terpolymer composition as a function of conversion and the three-dimensional terpolymer CCD showed excellent agreement with the experiments. The GPEC® elution chromatogram of the terpolymer was found to be in accordance with the predicted CCD and the experimentally determined CCD. © 1996 John Wiley & Sons, Inc.

The extension of the “restricted” penultimate scheme of binary copolymerization to ternary systems

AbstractThe so‐called “restricted” penultimate scheme of binary copolymerization — first presented by Fukuda et al. — is extended to ternary systems without introducing extra parameters not inherent in the three binary systems which form the ternary systems. The crucial assumption is that the restricted penultimate effect is only dependent (1) on the type of monomer forming the terminal radical and (2) the monomer replacing this type of monomer in the penultimate unit, but is independent of the monomer to be added. Accordingly, the scheme is fully described by quantities taken from the binary copolymerizations forming the ternary system. This general principle is still valid when the number of different monomers in the copolymerization system is even increased beyond three. Comparison between predicted values of the phenomenological propagation constant k̄p with the few experimental data available for terpolymerization systems indicates a satisfactory agreement.

High solids content emulsion terpolymerization of vinyl acetate, methyl methacrylate and butyl acrylate. II. Open loop composition control

AbstractA method for the calculation of the optimal monomer addition policies for polymer composition control in emulsion terpolymerization is developed. The method is applied to reactors with and without limited heat removal capacity. A mathematical model that incorporates the main features of the vinyl acetate/methyl methacrylate/butyl acrylate high solids content emulsion terpolymerization system allows the calculation of the composition of the initial charge of the reactor and the time‐dependent monomer addition rates required. © 1994 John Wiley & Sons, Inc.

Influence of reactor operational policies on distributions of chemical composition, molar mass, sequence length and sequence frequency of multicomponent polymers obtained by free‐radical polymerization

AbstractRemarkable shifts in chemical composition, molar mass, sequence length and sequence frequency will occur in the course of free‐radical multicomponent polymerizations, if the reactivities of the comonomers are different and a simple batch reactor is used. It is shown for the terpolymerization system of methyl methacrylate/styrene/maleic anhydride that a semi‐batch reactor with appropriate regimes is suitable to obtain products with improved chemical, molecular and sequential homogeneity. However, if polymers with defined inhomogeneities like bimodal molar mass or chemical composition distributions are desired, these are also obtainable by use of appropriate operational policies, which will be illustrated for the homopolymerization of methyl methacrylate and the binary copolymerization of methyl methacrylate/maleic anhydride. Concerning the instantaneous mean chemical composition of polymer molecules, which cannot be measured directly, a new procedure is presented to determine this quantity experimentally.

Copolymerization of vinyl ketones with allylbenzene in the presence of zinc chloride

AbstractCopolymerization of 3‐buten‐2‐one (MVK) and 3‐methyl‐3‐buten‐2‐one (MIPK) with allylbenzene (AB) in the presence of zinc chloride (ZnCl2) was studied. The apparent monomer reactivity ratio decreased with an increasing concentration of ZnCl2 added. By assuming a terpolymerization system as free vinyl ketone (M1), vinyl ketone complexed with ZnCl2 (M2), and AB(M3), the absolute monomer reactivity ratios were determined by using the least squares method: k11/k12 = 0.0038, k11/k13 = 11.77, k22/k21 = 1.37, and k22/k23 = 3.77 for the MVK‐AB system, and k11/k12 = 0.0070, k11/k13 = 55.47, k22/k21 = 1.84, and k22/k23 = 11.16 for the MIPK‐AB system, respectively. It is seen from these values that the complexed vinyl ketones are more reactive to both polymer radicals which have free and complexed vinyl ketone units at its terminal position than the free vinyl ketones. Q and e values for MVK and MIPK complexed with ZnCl2 were found to be Q = 850, e(MVK)2ZnCl2 = 2.97, Q = 2.62, respectively.

Photoinitiation, 7. Terpolymerization of the system acrylonitrile/maleic anhydride/styrene

AbstractThe photoinitiated (at wavelength λ = 365 nm) terpolymerization of acrylonitrile, maleic anhydride and styrene in the presence and/or absence of additives such as ZnCl2 or N,N‐dimethylaniline (DMA) in acetone was studied, and the relative reactivities R of maleic anhydride and acrylonitrile towards a styryl radical were determined. In the presence of ZnCl2 and/or DMA, the relative reactivities R are by about 40% lower than the value of R (= 13,3 ± 2,1) for the terpolymerization system without additives.

Ferrocene‐containing polymers. II. Radiation‐induced copolymerizations of ferrocenylmethyl methacrylate with styrene, methyl methacrylate, and ethyl acrylate

AbstractFerrocenylmethyl 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 Q–e 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.

Graphical Representation of Terpolymerization Systems

Abstract As a modification and improvement of Slocombe's and O'Driscoll's terpolymerization patterns, a new graphical representation of terpolymer systems has been proposed. The suggested patterns retain all the information necessary to describe ternary systems, including also those related to their azeotropic behavior. The main advantage of the proposed representation is its similarity to the accustomed binary representation: the sides of the composition triangles depict the behavior of the corresponding binary systems.

Simulation of kinetic analysis on terpolymerization of styrene/butyl methacrylate/methacrylic acid system

The simultaneous differential equations which connected the copolymerization kinetics of the component reaction in the multi-copolymerization system with the changing rate of the concentration of each monomer and radical, the concentration and the molecular weight of the polymer obtained are analysed in a number of ways. The distribution of the components and the degree of polymerization are also simulated. The styrene/butyl methacrylate/methacrylic acid terpolymerization system, using carbon tetrachloride as solvent and benzoyl peroxide as initiator, was chosen. The simulation model which satisfied the experimental values of the concentration of the multiple components in the system, the composition and molecular weight distribution and the number of chlorine atoms introduced into the copolymer ends is established. When the time interval changed, the effects on the distribution of the composition in copolymers and the distribution of the degree of polymerization were also calculated.