Styrene-starch graft copolymers

Graft copolymers of nylon, protein, cellulose, starch, copolymers, or vinyl alcohol have been prepared by the reaction of ethylene oxide with these polymers. Graft copolymers are also produced when styrene is polymerized by Lewis acids in the presence of poly-p-methoxystyrene. The Merrifield synthesis of polypeptides is also based on graft copolymers formed from chloromethaylated PS. Thus, the variety of graft copolymers is great. 

The ozonization method has been extended to the most varied polymer/monomer systems, such as polybutadiene-03 with acrylamide, methyl methacrylate or styrene, cellulose-03 with styrene or acrylonitrile (127), starch-03 with styrene (126). In this last case the formation of some homopolystyrene as side-product has been mentionned by the authors. The starch-styrene graft copolymers are claimed to be good emulsifiers for water-oil suspensions. 

While starch copolymers are typically prepared by batch polymerization methods, reactive extrusion of starch has been studied. Mixtures of starch, polystyrene, styrene, sodium hydrogen carbonate, citric acid and water were extruded at temperatures between 100°C and 200°C.118 It was reported that expanded graft copolymers... 

Graft copolymers of thinned, gelatinized starch, including hydroxyethyl starch, with 1,3-butadiene-styrene latexes and other polymers that are claimed to have useful properties as paper coating materials are presented in Chapter 17. 

Graft copolymers like 1-27 are named aspoly(A-g-B) with the backbone polymer mentioned before the branch polymer. Examples are poly(ethylene- -styrene) or starch-g-polystyrene. In block copolymer nomenclature b is used in place of g and the polymers are named from an end of the species. Thus the triblock macromolecule 1-53... 

Graft copolymers of A and B monomers are named poly(A-g-B) or poly -graft-po y B with the backbone polymer -(-A-) - mentioned before the branch polymer. Some examples are poly(ethylene-g-styrene) or polyethylene-gra/it-polystyrene and starch-gra/ir-polystyrene. In the nomenclature of block copolymers, b or block is used in place of g or graft, e.g. poly(A-b-B) or poly A-block-poly B, poly(A-6-B-6-A) or poly A-6/ocik-poly B-blocic-po y A, poly(A-b-B-6-C) or poly A-6/ock-poly B-block-po y C), and so on. Thus the triblock polymer (XXIV) is called poly(styrene-6-butadiene-b-styrene) or polystyrene-6/ocA -polybutadiene-6/ock -polystyrene. When such polymers are articles of commerce they are usually designated by the monomer initials thus, structure (XXIV) would be named SBS block copolymer. 

There have been many studies of graft copolymer formation initiated by ionizing radiation, and methods have been discussed.88 Among the systems studied are styrene onto polyethylene,88 styrene onto polypropylene,100 styrene onto Nylon-6,101 styrene onto ethylene-vinyl acetate copolymers,102 styrene and MMA onto natural rubber,103 pentafluorostyrene onto Nylon and polyethylene,104 acrylamide onto Nylon-6,105 acrylamide onto starch,100 vinyl monomers... 

Graft copolymers of A and B monomers are named poly(A-g-B) or poly A-graft-poly B with the backbone polymer -(-A-), — mentioned before the branch polymer. Some examples are poly(ethylene-g-styrene) or polyethylene-grayi-polystyrene and starch-gro -poly(methylmetha-... 

Graft copolymers of polychloroprene and a cationic starch imparted wet-strength properties to paper when applied as wet-end additives to pulp, and they also exhibited cold-contact adhesive properties without pressure being applied. Poly(styrene-n//-acrylonitrile) has been grafted onto starch. ... 

Sodium dodecyl sulfate micelle 71,72,77,79 Spin label 139 Starch 100, 104 —, crosslinked 106 —, graft polymers 105, 107, 125, 127 Styrene 160—162 Styrene-divinylbenzene resins 167 Styrenesulfonic acid, copolymers 74—76 Surface area 147... 

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