Copolymerization of styrene with acrylonitrile and maleic anhydride

The complex formation constants for styrene (donor)-acrylonitrile (acceptor) and styrene-maleic anhydride (acceptor) systems are found to be 0.19 ± 0.01 and 0.28 ± 0.01 l/mol (¹H NMR, CCl₄, 298 K); the same values are characteristic for three-component systems of these monomers. The calculated ΔH ₀ values (the AM1 method) for styrene-acrylonitrile (C₁) and styrene-maleic anhydride (C₂) complexes comprise ?1.24 and ?2.30 kJ/mol. Changes in charges on double bonds of complex-bonded molecules are in the range from 0.001 to 0.006 au. These values are typical of π-π complexes. By analyzing the composition and rate of bulk copolymerization (333 K, 0.03 mol/l AIBN), we have shown that two complexes are involved in chain propagation: r ₁ = $ k_{2C_1 } /k_{2C_2 } $ = 0.26 ± 0.015 and r ₂ = $ k_{3C_2 } /k_{3C_1 } $ = 4.17 ± 0.143.     

Copolymerization of styrene with maleic anhydride initiated by thiol compounds

Copolymerization of styrene (ST) with maleic anhydride (MAH) initiated by thiol compound was investigated under various conditions. The kinetics of copolymerization of ST with MAH initiated by p-toluenethiol (pTT) was studied in dioxane in the temperature range of 25–60°C, and the rates (R_p) of copolymerization and activation energy were determined. R_p was found to depend on [pTT],^0.6 ([ST] + [MAH])^2.7. The overall energy of activation was 10.8 kcal/mol in the temperature range of 25–60°C. A mechanism involving the formation of a complex between MAH and pTT the decomposition of which yields the initial radical is suggested.     

Cationic polymerization of 4-methyl-1,3-dioxene-4 and copolymerization with tetrahydrofuran

A new monomer, 4-methyl-1,3-dioxene-4 was synthesized from allyl chloride and paraformaldehyde. The monomer was polymerized at room temperature or ?78°C. by boron trifluoride etherate catalyst, and the structure of the obtained polymer was determined by infrared, nuclear magnetic resonance spectra, and chemical analysis. It was ascertained that the polymerization process proceeded through a ring-opening mechanism at the dioxane ring. In the presence of tetrahydrofuran, the polymerization of 4-methyl-1–1,3-dioxene-4 led to copolymer. The mechanism of the copolymerization is described in detail.     

Spontaneous copolymerization of 4-methylene-1,3-dioxolanes with maleic anhydride

The copolymerization of methylenedioxolanes, such as 4-methylene-1,3-dioxolane (I) and 2,2-dimethyl-4-methylene-1,3-dioxolane (II), with maleic anhydride (Manh) gives rise spontaneously to the alternating copolymers by the participation of charge-transfer (CT) complexes. The formation of CT complexes I-Manh and II-Manh was ascertained by UV and NMR spectroscopies. The equilibrium constants (K) could not be determined but were assumed to be small (K ? 1). For comparison with these systems an investigation of I-dimethyl maleate (DMM) and II-DMM systems was carried out to estimate K values 0.115 and 0.157 L/mol, respectively. To clarify the copolymerization mechanism I-Manh-acryronitrile was terpolymerized. Consequently it was concluded that the spontaneous copolymerization of I-Manh and II-Manh systems is effected by the CT complex monomer mechanism.     

Complex-radical terpolymerization of phenanthrene,maleic anhydride,and trans-stilbene

The radical terpolymerization of the donor-acceptor-donor monomer system, phenanthrene (P)—maleic anhydride (M)—trans-stilbene (S), was studied. These monomers are known to be nonhomopolymerizable. The terpolymerization was carried out in p-dioxane and/or toluene at 70°C in the presence of benzoyl peroxide used as the initiator. P and S were found to form charge transfer complexes (CTC) with M in p-dioxane at 35°C. The results obtained are discussed in terms of the free monomer and complex propagation models. It is shown that terpolymerization is carried out at a stage close to binary copolymerization of two complexomers. The reactivity ratio of P … M and S … M complexes was estimated by the Kelen-Tüdös method. Absorbance ratios at 1770 cm^?1 (v_C=0 of anhydride group), 764 cm^?1 (δ_CH in monosubstituted benzene of S), and 820 cm^?1 (δ_CH in disubstituted benzene of P) as a function of terpolymer composition were established. P—M—S terpolymers are shown to have high thermal stabilities. © 1995 John Wiley & Sons, Inc.     

Ferrocene as an effective initiator for copolymerization of styrene with maleic anhydride

Ferrocene (Fc) was found to be an effective initiator for copolymerization of styrene (ST) with maleic anhydride (MAH). Copolymerization could be initiated by charge transfer complex formed between MAH as an electron acceptor and Fc as an electron donor. A good relationship between the formation of charge transfer complex and initiation activity was observed in the copolymerization of ST with MAH in various solvents. Overall energy of activation determined from an Arrhenius plot in dioxane was found to be 21.8 kJ/mol. © 1995 John Wiley & Sons, Inc.     

Copolymerization of maleic anhydride with certain compounds of the vinyl series

Russian Chemical Bulletin -     

Blends of styrene/maleic anhydride copolymers with polymethacrylates

The phase behavior of a series of styrene/maleic anhydride (SMA) copolymers with various polyacrylate and polymethacrylate homopolymers has been investigated using various techniques. None of the polyacrylates are miscible with SMA copolymers. Poly (methyl methacrylate) (PMMA) poly(ethyl methacrylate) (PEMA) and poly(n-propyl methacrylate) (PnPMA), are miscible with these copolymers over a certain range of maleic anhydride contents; whereas, the higher methacrylates apparently have no region of miscibility. For PEMA and PnPMA, the miscibility windows extend through 0% MA; hence, polystyrene is miscible with these polymethacrylates although the lower critical solution temperature is quite low. The exothermic heat of mixing styrene and ester analogs found here supports the observed miscibility of polystyrene with ethyl, n-propyl, and cyclohexyl (reported elsewhere) methacrylates. Lattice fluid interaction parameters for styrene-methacrylate obtained from the cloud points of these blends agree quite well with the Flory—Huggins parameters obtained from copolymer miscibility windows.     

Copolymerization of furan with maleic anhydride initiated by thioglycolic acid

Copolymerization of furan (F) with maleic anhydride (MAH) initiated by thioglycolic acid (TGA) was studied in various solvents and temperatures in the presence of atmospheric oxygen. Copolymer between F and MAH was readily obtained by using thiol compounds as initiators. The atmospheric oxygen catalyses the copolymerization reaction. The rate of copolymerization is proportional to the concentration [TGA]^0.55 at low concentrations (< 1.0 mol/L), at higher concentrations rates decrease gradually. The copolymerization rate increases with increase in copolymerization temperature and varies with the total monomer concentration as ([F] + [MAH])^1.9. The overall energy of activation as calculated from the Arrhenius plot has been found to be 6.4 Kcal/mol within the temperature range of 25–50°C.     

热重法测定高马来酸酐含量苯乙烯-马来酸酐共聚物的组成

高马来酸酐含量苯乙烯-马来酸酐共聚物(SMA)是一种具有优良耐热性、刚性和尺寸稳定性的新型高分子材料.由于SMA分子中含有极性很强、反应活性很高的酸酐官能团,所以它被广泛应用于涂料、粘合剂的改性剂、地板抛光的乳化剂、复合材料和颜料的分散剂、水处理剂等领域[1-5].     

Copolymerization of 2-phenylvinyl alkyl ethers and maleic anhydride

A series of 2-phenylvinyl alkyl ethers (I) having as alkyl group methyl, ethyl, n-propyl, n-butyl, 2-methylbutyl, 3-methylpentyl, and optically active 1-methylpropyl of (S) absolute configuration, were copolymerized with maleic anhydride to alternating copolymers. The copolymerizations were carried out in bulk at 70°C in the presence of AIBN as initiator. Monomer I (R = Et) was also polymerized with lauroyl and benzoyl peroxide as initiator. The yield and molecular weight were highest when equimolar amounts of both monomers were used. The equilibrium constant of charge-transfer complex of monomer I (R = Et) and maleic anhydride was determined by the transformed Benessi-Hildebrand NMR method and has a value of 0.28 mole/1.     

4-PEG接枝苯乙烯-马来酸酐交替共聚物的合成及功能化

采用普通自由基聚合和可逆加成一断裂链转移（RAFT）自由基聚合方法合成了对位PEG取代苯乙烯（PEG-g-St）和马来酸酐的交替共聚物（P（（PEG—g—St）-alt-MA））,”CNMR分析表明PEG-g-St和马来酸酐单元采取交替的序列结构．利用反应性基团-马来酸酐单元的水解以及胺解可以制备功能性的PEG聚合物．以月桂胺为模型小分子研究了该聚合物的胺解,得到4-PEG-苯乙烯与羧酸基团以及疏水烷烃的交替序列聚合物,该双亲聚合物在水溶液中形成组装体．     

Thermal studies of copolymers of styrene and maleic anhydride

Copolymers of styrene and maleic anhydride prepared by a charge transfer mechanism have been studied thermally by thermogravimetry and differential scanning calorimetry. The copolymers degrade in two stages; the first stage accounts for about 85% of the degradation. Incorporation of maleic anhydride to styrene decreases the thermal stability of the later. Differential scanning calorimetric studies show two exotherms between 300° to 500 °C. Glass-transition temperatures for the copolymers are lower than that of polystyrene.     

Living radical copolymerization of styrene/maleic anhydride

Styrene/maleic anhydride (MA) copolymerization was carried out using benzoyl peroxide (BPO) and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO). Styrene/MA copolymerization proceeded faster and yielded higher molecular weight products compared to styrene homopolymerization. When styrene/MA copolymerization was approximated to follow the first‐order kinetics, the apparent activation energy appeared to be lower than that corresponding to styrene homopolymerization. Molecular weight of products from isothermal copolymerization of styrene/MA increased linearly with the conversion. However products from the copolymerization at different temperatures had molecular weight deviating from the linear relationship indicating that the copolymerization did not follow the perfect living polymerization characteristics. During the copolymerization, MA was preferentially consumed by styrene/MA random copolymerization and then polymerization of practically pure styrene continued to produce copolymers with styrene‐co‐MA block and styrene‐rich block. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2239–2244, 2000     

Linear nano-templates of styrene and maleic anhydride alternating copolymers

Poly(styrene-alt-maleic anhydride) (SMA) self-assembles in aqueous solution to form nanotube structures. These can be used as templates to linearly guide the growth of a secondary polymeric or inorganic material. Templates are made starting from a basic SMA solution, followed by slow pH decrease by dialysis against deionized water, until a 50% degree of protonation is reached. The nanotube structure is composed of multiple polymer chains, associating sideways by π-stacking to form the nanotube walls. The SMA templates were used to grow linear composites, which shows the applicability of the template properties and also confirms the nanotube association mechanism. Linear polymer composites were formed using this SMA template: pyrrole was polymerized, silver nitrate was reduced to silver and silver cyanide nanowires were grown.     

Laser-initiated copolymerization of maleic anhydride with styrene,vinyltoluene, and t-butylstyrene

Laser-initiated polymerization of charge transfer monomer complexes has been investigated using an argon ion laser. The influence of solvents, monomer feed ratio, and irradiation time on the copolymer yield and composition was evaluated. The polymer yield was found to be directly proportional to the irradiation time and the molar concentration of maleic anhydride in the monomer feed. An enhanced rate of polymerization was obtained by substituting electron donating groups in the donor monomer. Polymerization, initiation, and propagation mechanisms, via charge transfer complexes, have been discussed. Comparison of laser-induced polymerization with UV-induced polymerization suggests that laser initiation is an energy-efficient process.