Blending of styrene/acrylonitrile

A commercially important example of the special case where one monomer is the same in both copolymers is blends of styrene—acrylonitrile, 1 + 2, or SAN copolymers with styrene—maleic anhydride, 1 + 3, or SMA copolymers. The SAN and SMA copolymers are miscible (128,133,144) so long as the fractions of AN and MA are neatly matched, as shown in Figure 4. This suggests that miscibility is caused by a weak exothermic interaction between AN and MA units (128,133) since miscibility by intramolecular repulsion occurs in regions where 02 7 can be shown (143) by equation 11. 

Fig. 4. Miscibihty map for blends of styrene—acrylonitrile copolymers (SAN), with styrene—maleic anhydride copolymers (SMA).

This method involves the mechanical blending of styrene-acrylonitrile copolymers and acrylonitrile-butadiene rubbers. Many products are possible depending on the composition of each copolymer and the relative amounts employed. 

ABS is a blend of styrene/acrylonitrile-copolymer with butadiene/slyrene-copolymer... 

J.A. Herbig and 1.0. Salyer, Binary blends of styrene/acrylonitrile copolymer and butyl acrylate/acry-lonitrile copolymer and methods for preparing the same, US Patent 3118855, assigned to Monsanto Chemicals, January 21,1964. 

M. Fowler, J. Barlow, and D. Paul, Effect of copolymer composition on the miscibility of blends of styrene-acrylonitrile copolymers with poly (methyl methacrylate), Polymer, 28(7) 1177-1184, June 1987. 

Table III. Blends of Styrene—Acrylonitrile—DBPF Resins with Nitrile Rubbers "...

Motionless Mixer Blending of Styrene/ Acrylonitrile Copolymer and Nitrile Rubber to Form ABS... 

Selected blends of styrene-acrylonitrile copolymer (30 to 55%), a styrene-butadiene copolymer grafted with styrene and acrylonitrile (45 to 70%), and a coal-tar pitch (0 to 25%), were prepared. Physical properties of the experimental blends were determined and statistical techniques were used to develop empirical equations relating these properties to blend composition. Scheff canonical polynominal models and response surfaces provided a thorough understanding of the mixture system. These models were used to determine the amount of coal-tar pitch that could be incorporated into ABS compounds that would still meet ASTM requirements for various pipe-material designations. ... 

The two most important ways of producing ABS polymers are (1) blends of styrene-acrylonitrile copolymers with butadiene-acrylonitrile rubber, and (2) interpolymers of polybutadiene with styrene and acrylonitrile, which is now the most important type. A typical blend would consist of 70 parts styrene-acrylonitrile (70 30) copolymer and 40 parts butadiene-acrylonitrile (65 35) rubber. 

Alloy a- 16i also 9- loi [F aloi, fr. OF alei, fr. aleir to combine, fr. L alligare to bind] (1604) n. A blend of a polymer or copolymer with other polymers or elastomers. An important example is a blend of styrene-acrylonitrile copolymer with butadiene-acrylonitrile rubber. The term polyblend is sometimes used for such mixtures. Some... 

In 1946 Naugatuck Chem. Co. introduced i oyaif e, a mechanical blend of styrene-acrylonitrile copolymer, SAN, and NBR, known as ABS-type A [Daly, 1948]. The contemporary version of ABS, so-called ABS-type G, was invented in 1950 by emulsion-grafting of crosslinked polybutadiene particles with styrene and acrylonitrile. The material gained wide application — ABS is a component in about 25% polymer blends. In 1986 these materials constituted 74% of all blends sold in Europe, 77% in Japan, and 69% in North America. 

The products obtained by this method are mechanical blends of styrene-acrylonitrile copolymers and acrylonitrile-butadiene rubbers. The preferred method of preparation is by blending latices of the two copolymers and coagulating the mixture. A wide range of products is possible, depending on the composition of each copolymer and the relative amounts of each employed. A typical blend would consist of the following (solids) ... 

NC Inceoglu, S., Young, N.P., Jackson, A.J., Kline, S.R., Costeux, S., and Balsara, N.P., Effect of supercritical carbon dioxide on the thermodynamics of model blends of styrene-acrylonitrile copolymer and poly(methyl methacrylate) studied by small-angle neutron scattering, Macrowro/ecM/ex, 46, 6345, 2013. 

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