Styrene, copolymers with maleic anhydride

DEPT was used to generate subspectra of copolymers of styrene (S) with maleic anhydride (MAn) [53]. The normal spectrum of an S-MAn copolymer with a composition of 52% styrene consists of three broad resonances that display fine structure (Fig. 6.20). 

Gilsonite is active as a fluid loss additive because the permeability of cement is reduced. Latex additives also act as fluid loss additives. They also act as bonding aids, gas migration preventers, and matrix intensifiers. They improve the elasticity of the cement and the resistance to corrosive fluids [921]. A styrene-butadiene latex in combination with nonionic and anionic surfactants shows less fluid loss. The styrene-butadiene latex is added in an amount up to 30% by weight of the dry cement. The ratio of styrene to butadiene in the latex is typically 2 1. In addition, a nonionic surfactant (octylphenol ethoxylate and polyethylene oxide) or an anionic surfactant, a copolymer of maleic anhydride, and 2-hydroxypropyl acrylate [719] can be added in amounts up to 2%. 

A special case of asymmetric enantiomer-differentiating polymerization is the isoselective copolymerization of optically active 3-methyl-1-pentene with racemic 3,7-dimethyl-1-octene by TiCl4 and diisobutylzinc [Ciardelli et al., 1969]. The copolymer is optically active with respect to both comonomer units as the incorporated optically active 3-methyl-l-pentene directs the preferential entry of only one enantiomer of the racemic monomer. The directing effect of a chiral center in one monomer unit on the second monomer, referred to as asymmetric induction, is also observed in radical and ionic copolymerizations. The radical copolymerization of optically active a-methylbenzyl methacrylate with maleic anhydride yields a copolymer that is optically active even after hydrolytic cleavage of the optically active a-methylbenzyl group from the polymer [Kurokawa and Minoura, 1979]. Similar results were obtained in the copolymerizations of mono- and di-/-menthyl fumarate and (—)-3-(P-styryloxy)menthane with styrene [Kurokawa et al., 1982],... 

Chirality induction can be achieved in homo- and copolymerization of vinyl monomers based on chiral monomer structure [1,3,8,9]. The first example of this type of polymerization was the copolymerization of (S)-a-methylbenzyl methacrylate with maleic anhydride the polymerization product showed [a]D +23° after removal of the chiral side group [73]. For another example, the copolymerization of an optically active styrene derivative (39) with N-phenylmaleimide (17, R = -Ph) followed by removal of the optically active side group and deboronation gave an optically active N-phenylmaleimide-styrene copolymer [74]. 

The interactions of a-olefins or styrene with sulfur dioxide (16) or a-olefins (24, 58, 78), frans-stilbene (64), styrene (1,63), p-dioxene (52), 2,2-dimethyl-l,3-dioxole (17), or alkyl vinyl ethers (1, 63) with maleic anhydride yield charge transfer complexes which are stable and generally readily detectable either visually or by their ultraviolet absorption spectra. However, under the influence of a sufficiently energetic attack in the form of heat or free radicals, the diradical complexes open, and alternating copolymers are formed. 

A first successful attenpt to split water photochemically this way was made by us in 1979 (Ji2). A copolymer of maleic anhydride and styrene was used as a protective agent for the Pt sol. This is suitable to achieve selectivity since it provides functions with pronounced hydrophobicity. Of the redox products formed in the li t reaction MV is relatively hydrophobic and will therefore interact with the Pt. Ru(bipy)j on the other hand is prone to interact with the hydrophilic and negatively charged RUO2 surface. One disadvantage of this system is that the quant an yield of water splitting is small and that... 

There exist many alternating copolymerizations ethylene or propene with alkyl acrylates [244], vinyl acetate with maleic anhydride [245], styrene with acrylonitrile [246], styrene with fumaronitrile [247], vinyl carbazol with fumaronitrile, vinyl ferrocenne with diethylfumarate [248], and further pairs or systems of three monomers [238, 249-253]. External conditions can support or hinder alternation. At not too high temperatures, vinyl acetate forms a donor—acceptor complex with maleic anhydride. Under these conditions (and in the presence of a radical initiator), an alternating copolymer is formed. The concentration of the complex decreases with increasing temperature above 363 K the complex cannot exist. Under these conditions, copolymerization yields a statistical copolymer whose composition depends on the composition of the monomer mixture [245]. 

A stable free radical polymerization using 2,2,6,6-tetramethyl-l-piperidinyloxy with maleic anhydride and styrene was used to prepared moderate molecular weight copolymers with polydispersities less than 1.5. Thermal re-activation of these copolymers in the presence of other monomers produced block polymers. 

Koppers produced SMA moulding powders under the tradename Dylark . Arco has since acquired this business and continues to produce these SMA resins today under the Dylark tradename. Another styrene copolymer with better heat resistance than regular polystyrene is the copolymer of styrene and fumaronitrile which was reported in 1948 [27]. Both of these styrene copolymers are based on nonpolymerizable monomers - that is, fumaronitrile, like its corresponding anhydride (maleic anhydride), does not form homopolymers but readily copolymerizes with styrene at levels of up to 40%. Monsanto attempted to commercialize the styrene-fumaronitrile copolymer under the tradename Cerex , but residual fumaronitrile was a powerful vesicant (an irritant which causes blisters) and the project was shelved [28]. 

The electron richness of vinylferrocene as a monomer has been demonstrated in its copolymerization with maleic anhydride, in which 1 1 copolymers were obtained over a wide range of feed ratios and ri r2 = 0.003 [13]. Subsequent copolymerization of vinylferrocene with classic organic monomers, such as styrene [13], Ai-vinyl-2-pyrrolidone [15], methyl methacrylate [13] and acrylonitrile [13] were carried out and the Alfrey-Price Q and e parameters [16] determined. The value of e is a semiempirical measure of the electron richness of the vinyl group. The best value of e for vinylferrocene is about —2.1, which, when compared with the e values of maleic anhydride (-H 2.25), p-nitrostyrene (-1-0.39), styrene (—0.80), p-Ai,Ai -dimethyl-aminostyrene ( — 1.37) and l,T-dianisylethylene ( — 1.96), again emphasizes the electron rich nature of the vinyl group in vinylferrocene. 

Through copolymerization there can be made materials with different properties than those of either homopolymer, and thus another dimension is added to the technology. Consider, for example, styrene. Polymerized alone, it gives a good electric insulator that is molded into parts for radios, television sets, and automobiles. Copolymerization with butadiene (30%) adds toughness with acrylonitrile (20-30%) increases resistance to impact and to hydrocarbons with maleic anhydride yields a material that, on hydrolysis, is water-soluble, and is used as a dispersant and sizing agent. The copolymer in which butadiene predominates (75% butadiene, 25% styrene) is an elastomer, and since World War II has been the principal rubber substitute manufactured in the United States. 

Recent studies in our laboratory were aimed at defining more closely the conditions governing Intramolecular excimer formation in dilute polymer solutions (15). An alternating copolymer of styrene with maleic anhydride or methylmethacrylate showed no excimer emission, confirming that interactions of other than neighboring phenyl residues made no significant contribution to... 

PolyCACN) has a rigid chain structure yet can form excimers with alternate units along the chain (8), or by stacking in a helical conformation. Excimer formation has been reported for alternate copolymers of ACN with styrene (9) and for ACN with maleic anhydride CIO). The situation is different for 2-vinylnaphthalene since alternating copolymers of 2VN with methyl methacrylate or methacrylic acid did not form excimers, yet random copolymers of the same systems showed excimer fluorescence Cll). Only random copolymers of ACN were prepared in this work. 

Alkyl phenol ethoxylates can also react with P4O10 yielding alkyl phenol etherphosphates as a mixture of mono-/diesters or with maleic anhydride to yield maleic acid monoesters, which then react with NaHS03 to yield sulphosuccinate monoesters. Alkylphenolpolyglycolether sulphates, phosphates or sulphosuccinates are mainly used as primary anionic emulsifiers for the manufacturing of acrylic, styrene/acrylic or vinyl acetate co-polymer dispersions. Another type of non-ionic emulsifier is block copolymers of ethylene oxide with propylene oxide. 

The rates of radical-monomer reactions are also dependent on considerations of steric effects. It is observed that most common 1,1-disubstituted monomers — for example, isobutylene, methyl methacrylate and methacrylo-nitrile—react quite readily in both homo- and copolymerizations. On the other hand, 1,2-disubstituted vinyl monomers exhibit a reluctance to ho-mopolymerize, but they do, however, add quite readily to monosubstituted, and perhaps 1,1-disubstituted monomers. A well-known example is styrene (Ml) and maleic anhydride (M2), which copolymerize with r — 0.01 and T2 = 0 at 60°C, forming a 50/50 alternating copolymer over a wide range of monomer feed compositions. This behavior seems to be a consequence of steric hindrance. Calculation of A i2 values for the reactions of various chloroethylenes with radicals of monosubstituted monomers such as styrene, acrylonitrile, and vinyl acetate shows that the effect of a second substituent on monomer reactivity is approximately additive when both substituents are in the 1- or cr-position, but a second substituent when in the 2- or /3-position of the monomer results in a decrease in reactivity due to steric hindrance between it and the polymer radical to which it is adding. 

Photosensitized crosslinking of polymers has been the subject of numerous publications [l - 30], concerned mainly with poly(ethylene), poly(vinyl alcohol), various vinyl copolymers, copolymers of maleic anhydride and/or phtalic anhydride with styrene and some polymers derivated from cinnamic acid. The following compounds were used as sensitizers benzophenone, 4-chloro- and 4,4-dimethylbenzophenone [l, 3-6, 8, 9l, oC -and -derivatives of anthraquinone [3, 23] acetophenone, hydroquinone, triphenylmethane and pyridine li.] chlorobenzene and no less than trichlorinated n-paraffins [6], a complex of zink chloride with o-dia-nizidine fill potassium bichromate [l2j, anthracene fl3, 14] 2,5-methoxy-4-amino-trans-stilbene [l5], benzyl ideneacetophenone fl6-l8] -thiophenylacetophenone,... 

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