Styrene-maleic anhydride alternating copolymer

Figure 4. Fluorescence spectra of (a) poly(styrene) and (b) styrene/maleic anhydride alternating copolymer in tetrahydrofuran at 20°C. Excitation wavelength 265 nm.

The infrared spectograms were obtained on a Beckman IR-10 instrument. Solutions of the styrene-maleic anhydride alternating copolymer and styrene block copolymer were used. A KBr pellet was used for the spectogram of the methyl methacrylate block copolymer. 

Poly(S-a/f-maleic anhydride)-g-PEO grafts were prepared by reacting monoamine terminated poly(ethylene oxide) with the styrene-maleic anhydride alternating copolymers [70]. The samples were characterized by SEC and UV-VIS and NMR spectroscopy. 

Styrene—maleic anhydride (SMA) copolymers are used where improved resistance to heat is required. Processes similar to those used for SAN copolymers are used. Because of the tendency of maleic anhydride to form alternating copolymers with styrene, composition drift is extremely severe unless the polymerization is carried out in CSTR reactors having high degrees of back-mixing. 

Another route toward potentially amphiphilic copolymers is the copolymerization of styrene with maleic anhydride, which has the particularity to lead to poly(styrene-co-maleic anhydride) alternate copolymers and ultimately to poly (styrene-co-maleic anhydtide)-b-polystyrene block copolymers after complete depletion in maleic anhydride. Maleimide comonomers were similarly copolymetized with styrene such... 

Using the r and tz values from Table 6-2, construct plots showing the initial copolymer composition as a function of the comonomer feed composition for the radical copolymerizations of methyl acrylate-methyl methacrylate and styrene-maleic anhydride. Are these examples of ideal or alternating copolymerization ... 

As shown in Figure 2, the rate of the heterogeneous copolymerization of styrene and maleic anhydride in benzene (8 = 9.2) is faster than the homogeneous copolymerization of these monomers in acetone (8 = 9.9). However, this rate decreases as the solubility parameter values of the solvents decrease in heterogeneous systems. Thus, the rate of copolymerization decreases progressively in xylene (8 = 8.8), cumene (8 = 8.5), methyl isobutyl ketone (8 = 8.4), and p-cymene (8 — 8.2). All of these rates were faster than those observed in homogeneous systems. The solubility parameter of the alternating styrene-maleic anhydride copolymer was 8 = 11.0. 

Typical chromatograms were observed when polystyrene was py-rolyzed in air and the pyrolytic products were analyzed by gas chromatography. A characteristic peak which was observed on the chromatograms obtained by the pyrolysis of maleic anhydride and the alternating styrene maleic anhydride copolymer but not with polystyrene was used as a reference peak. As shown in Table II, the ratio of the area under... 

It has also been reported that an aromatic carbon-hydrogen out of plane deformation band at 759 cm"1 was sensitive to sequence distribution in styrene-maleic anhydride copolymers (2). A shoulder was noted at this frequency in the infrared spectra of the block copolymer, but it was not possible to demonstrate differences in the spectra of the alternating and block copolymers with the instrumentation available. 

Zeng W and Shirota Y (1989) Studies on alternating radical copolymerization analysis of microstructures of styrene-maleic anhydride, styrene-acrylonitrile, and styrene-methyl methacrylate copolymers by fluorescence spectroscopy. Macromolecules 22 4204-8. 

There are a few alternative approaches to imide copolymers that allow the resin producer to make imide-modified high heat ABS without incurring the cost of the synthesized imide monomer. One is by reacting styrene-maleic anhydrides with a primary amine, either during the polymerization reaction with styrene or in a separate step. Mitsubishi Monsanto has practiced imidiza-tion on a commercial scale and described a process which follows the formation of S-MA with addition of amine and AN [60]. They described the manufacture of maleimide copolymers by heating the SMA copolymers with aniline in an extruder [61]. The maleimidation of the anhydride function is not complete, as there is unreacted amine or maleic anhydride in the product. The polymer stability and physical properties depend on the mole percent of maleimidation. 

Polysulfobetaines derived from alternating styrene-maleic anhydride copolymers 32 are easily prepared by ring opening of the anhydride moiety with 3-dimethylaminopropylamine, imidizing the resulting poly(amic acid) by heating, and alkylation with propane sultone [70-72]. For investigations of structure-property relationships additionally to 32b, the polymers 33 and 34 were synthesized [71]. The ionene-like polymer 33 was prepared... 

The tendency to alternation increases as the r V2 product nears zero, as long as both r and T2 are less than unity. Such copolymerizalions occur in free-radical systems when the two monomers have opposite polarities (Section 7.10.2). The styrene maleic anhydride copolymers mentioned in Chapter I are an example of a purely alternating system (ri = V2= 0), while styrene (Mi)-acrylonitrile (M2) copolymers have a pronounced tendency to alternate monomer residues (ri = 0.4, Y2 = 0). 

Li.gru.n-VeAd.ved Potyi ocqanaXeA Efforts to increase the incorporation of lignin into polyurethane products have concentrated on transforming polymeric lignins into polyisocyanates useful for reacting with polyols. Two alternative reaction pathways have been explored with the three lignin-like model compounds shown in Figure 3. These models were vanillic acid or a derivative thereof (Model Type A) a derivative of tetralin di-carboxylic anhydride (Model Type B) and a derivative of a styrene-maleic anhydride copolymer (Model Type C). 

Models Involving the Participation of Complexes As mentioned in Section 3.1, several copolymerizations that lead to alternating copolymers have been analyzed by the use of the concept of chain transfer complexes. Some of these systems are styrene-maleic anhydride [101-103], allyl acetate-maleic anhydride [104], and norbornene-maleic anhydride [105]. 

Kraton(tm) rubbers are block copolymers of styrene and butadiene. Styrene maleic anhydride copolymer is an alternate copolymer prepared using free radical initiators. Styrene and brominated styrene are copolymerized free radically to produce a random copolymer. 

The tendency for alternation of monomers in a styrene-maleic anhydride and styrene-acrylonitrile copolymers at moderate temperatures has been attributed to the formation of a charge transfer complex (CTC) between a donor (D) and an acceptor (A). This CTC is readily detectable by UV or nmR spectroscopy. More important, the equilibrium constant decreases as the temperature is increased and this effect can be followed by instrumental analysis. Thus it is possible to extrapolate to a higher temperature at which the CTC does not exist (16). Thus, by proper temperature control, it is possible to produce SMA alternating copolymers, block copolymers of vinyl monomers with both alternating and random SMA (17) and completely random copolymers of SMA (18). Half esters of SMA have been used as viscosity control agents in petroleum crudes (19). 

Styrene-Maleic Anhydride Copolymer n An alternating copolymer useful as a textile size and emulsifier. 

Gaylord [13-15] has succeeded in grafting substantial amounts of strictly alternating styrene/maleic anhydride chains onto a PO backbone by injecting styrene/maleic anhydride mixtures. These grafted copolymers are particularly attractive as the succinic anhydride from grafted copolymers is highly reactive and represent a route to the synthesis of new polymers. 

Side-chain polymers are usually prepared in the form of copolymers with NLO-active moieties attached on the backbone via flexible spacers such as methylene units. Examples are copolymers of methyl methacrylate and chromophore-substituted methacrylate monomers [53,61-63], poly(styrene-fy -acrylic acid ester) [54], and alternating styrene-maleic-anhydride copolymer [64], and there are many others. 

Polymerization of 4-vinylpyridine onto alternating styrene-maleic anhydride copolymer leads to similar results. Very low molecular weight (500) was found for poly(vinylpyridine) obtained onto template with molecular weight 4640. The authors explain the results in terms of the unfavorable location of the monomer units on the copolymer template. 

---